JP3645576B2 - Calculation method of engine rotation time - Google Patents

Description

[0001]
The present invention provides an engine for each input of a crank pulse representing a crank position. Half The present invention relates to an engine rotation time calculation method for calculating the latest time per rotation.
[0002]
[Prior art]
In recent years, microcomputers have been introduced into vehicles such as automobiles, and it has become possible to control engines, power trains and the like with high precision. As a result, in the development of vehicle control systems, the development of microcomputer software occupies a great deal of importance, and the efficiency of processing on the control algorithm has become an important issue.
[0003]
In the engine control system using the microcomputer described above, there are many processes for calculating the engine speed as one of the basic parameters, such as setting the fuel injection amount and setting the ignition timing. The engine speed is calculated based on crank pulse information representing the crank position output from the engine. (See Japanese Patent Laid-Open No. 4-171253)
In this case, the crank angle sensor is installed, for example, facing the outer periphery of the rotor connected to the crankshaft, and detects a plurality of protrusions or slits indicating a predetermined crank position on the outer periphery of the rotor and outputs them as crank pulses. The input interval time of this crank pulse is measured with a timer and the engine Half By converting the elapsed time per rotation, the engine speed can be calculated.
[0004]
[Problems to be solved by the invention]
However, conventionally, the input interval time of the crank pulse is measured by a timer and the engine Half When calculating the time per revolution, there are many systems that calculate based on the input interval time of the crank pulse measured at a specific crank angle. Half When calculating the time per revolution, the actual crank position will advance and it will not necessarily be based on the current driving situation. Half It does not become the time per rotation, and a slight error occurs in the engine control amount, which hinders precise control.
[0005]
In view of the above circumstances, the present invention provides an engine based on the latest data for each input of a crank pulse representing a crank position. Half An object of the present invention is to provide an engine rotation time calculation method that calculates the time per rotation, quickly grasps the current operation state, and enables precise control.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 A crank pulse is output corresponding to a plurality of crank angle positions set in advance for each half rotation of the engine, and each time the crank pulse is input, the crank pulse input interval time since the previous crank pulse is input is measured. In addition, the crank pulse input interval time equal to the number of crank pulses input per half engine revolution including the time value is memorized over time, and these time values are added together. engine Half The time per rotation is calculated.
[0007]
The invention according to claim 2 is the invention according to claim 1, wherein Half A table having an address corresponding to the crank position information for each crank pulse, which is the same as the number of crank pulses input per revolution, is provided at the corresponding address in the table for each crank pulse input. Stores the time from input to the current crank pulse input and adds the time stored in each address of the above table to the engine Half The time per rotation is calculated.
[0008]
[Action]
The invention described in claim 1 A crank pulse is output corresponding to a plurality of crank angle positions set in advance for each half rotation of the engine, and each time the crank pulse is input, the crank pulse input interval time since the previous crank pulse is input is measured. In addition, the crank pulse input interval time equal to the number of crank pulses input per half engine revolution including the time value is memorized over time, and these time values are added together. engine Half Calculate the time per revolution.
[0009]
The invention according to claim 2 is an engine Half There is provided a table having the same number of crank pulses input per rotation and having an address associated with the crank position information for each crank pulse. And , Ku For each rank pulse input, the time from the previous crank pulse input to the current crank pulse input is stored in the corresponding address of the table. And add the time stored in each address of the table and engine Half Calculate the time per revolution.
[0010]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a flowchart of a crank position calculation subroutine, FIG. 2 is a flowchart of periodic interrupt processing every 0.5 ms, FIG. 3 is a flowchart of classene interrupt processing, and FIG. 4 is job priority processing. 5 is a partial flowchart 1 of the job execution subroutine, FIG. 6 is a partial flowchart 2 of the job execution subroutine, FIG. 7 is a partial flowchart 3 of the job execution subroutine, FIG. 8 is a partial flowchart 4 of FIG. FIG. 10 is a flowchart of a CCAS / RCAS discrimination subroutine, FIG. 11 is a flowchart of an overflow interrupt process of a classen timer, FIG. 12 is an explanatory diagram showing a job execution state, and FIG. 13 is an explanation of a job flag. Figure, 14 is an explanatory diagram of a crank position variable, FIG. 15 is an explanatory diagram showing changes in a job execution flag and an overlap counter, FIG. 16 is an explanatory diagram of a system shift buffer, FIG. 17 is an explanatory diagram of a classen interval table, and FIG. FIG. 19 is a time chart showing the crank position and the stroke of the engine, FIG. 20 is a schematic configuration diagram of the engine system, FIG. 21 is a front view of the crank rotor and the crank angle sensor, and FIG. The front view of a cam rotor and a cam angle sensor, FIG. 23 is a circuit block diagram of an electronic control system.
[0011]
In the engine control system of this embodiment, an engine system shown in FIG. 20 is controlled by an electronic control unit (ECU) 50 having a microcomputer shown in FIG. 23 as a core, and fuel injection control, ignition timing control, and the like are performed. An operating system (OS) based on a new concept is installed in the microcomputer of the ECU 50, and by this OS, signal input processing from each sensor, engine speed calculation processing, intake air amount calculation processing, fuel injection amount setting Jobs for each control item such as processing and ignition timing setting processing are managed and executed efficiently.
[0012]
First, the engine system equipment configuration controlled by the ECU 50 will be described.
[0013]
As shown in FIG. 20, the engine 1 (showing a horizontally opposed four-cylinder engine in the figure) has an intake manifold 3 communicated with an intake port 2 a of a cylinder head 2, and an air chamber 4 is disposed upstream of the intake manifold 3. The throttle passage 5 is communicated with each other. An air cleaner 7 is attached to the upstream side of the throttle passage 5 via an intake pipe 6, and the air cleaner 7 communicates with an air intake chamber 8 that is an intake air intake port.
[0014]
An exhaust pipe 10 communicates with the exhaust port 2b via an exhaust manifold 9, and a catalytic converter 11 is interposed in the exhaust pipe 10 and communicates with a muffler 12. On the other hand, a throttle valve 5 a is provided in the throttle passage 5, an intercooler 13 is interposed in the intake pipe 6 immediately upstream of the throttle passage 5, and a resonator is provided downstream of the air cleaner 7 in the intake pipe 6. A chamber 14 is interposed.
[0015]
Further, an idle speed control valve (ISCV) 16 is interposed in a bypass passage 15 that connects the resonator chamber 14 and the intake manifold 3 to bypass the upstream side and the downstream side of the throttle valve 5a. Further, a check valve 17 is provided immediately downstream of the ISCV 16 and is opened when the intake pressure is negative, and is supercharged by the turbocharger 18 and closed when the intake pressure becomes positive. Yes.
[0016]
In the turbocharger 18, a compressor is interposed downstream of the resonator chamber 14 in the intake pipe 6, and a turbine is interposed in the exhaust pipe 10. Further, a wastegate valve 19 is interposed at the turbine housing inlet of the turbocharger 18, and a wastegate valve actuating actuator 20 is connected to the wastegate valve 19.
[0017]
The waste gate valve actuating actuator 20 is divided into two chambers by a diaphragm, one of which forms a pressure chamber communicating with the waste gate valve control duty solenoid valve 21, and the other opens the waste gate valve 19 in the closing direction. A spring chamber is formed in which an urging spring is stored.
[0018]
The waste gate valve control duty solenoid valve 21 is interposed in a passage communicating the resonator chamber 14 and the compressor downstream of the turbocharger 18 of the intake pipe 6, and the duty of the control signal output from the ECU 50. In accordance with the ratio, the pressure on the resonator chamber 14 side and the pressure on the downstream side of the compressor are adjusted and supplied to the pressure chamber of the actuator 20 for operating the wastegate valve.
[0019]
That is, the ECU 50 controls the waste gate valve controlling duty solenoid valve 21 and operates the waste gate valve actuating actuator 20 to adjust the exhaust gas relief by the waste gate valve 19, whereby the turbocharger 18. The supercharging pressure by is controlled.
[0020]
An absolute pressure sensor 22 communicates with the intake manifold 3 via a passage 23, and the intake pipe pressure / atmospheric pressure selectively communicates the absolute pressure sensor 22 with the intake manifold 3 or the atmosphere. A switching solenoid valve 24 is interposed.
[0021]
Further, an injector 25 is provided immediately upstream of each intake port 2a of each cylinder of the intake manifold 3, and an ignition plug 26a is attached to each cylinder of the cylinder head 2 to expose the tip of the cylinder 25 in the combustion chamber. An igniter 27 is connected to an ignition coil 26b that is connected to the ignition plug 26a.
[0022]
Fuel is pumped into the injector 25 from an in-tank type fuel pump 29 provided in the fuel tank 28 through a fuel filter 30 and is regulated by a pressure regulator 31.
[0023]
Further, an intake air amount sensor 32 such as a hot wire type or a hot film type is interposed immediately downstream of the air cleaner 7 of the intake pipe 6, and a throttle opening sensor 33a and an idle switch 33b are connected to the throttle valve 5a. Are continuously provided.
[0024]
Further, a knock sensor 34 is attached to the cylinder block 1a of the engine 1, and a cooling water temperature sensor 36 is exposed to a cooling water passage 35 communicating with both the left and right banks of the cylinder block 1a, whereby the exhaust manifold 10 of the exhaust pipe 10 is exposed. The O2 sensor 37 is exposed to the nine gathering parts.
[0025]
A crank rotor 38 is mounted on the crankshaft 1b supported by the cylinder block 1a, and a crank angle sensor 39 made of an electromagnetic pickup or the like is provided on the outer periphery of the crank rotor 38. Further, a cam angle sensor 41 for discriminating a cylinder made up of an electromagnetic pickup or the like is provided on the cam rotor 40 connected to the camshaft 1c of the engine 1. The crank angle sensor 39 and the cam angle sensor 41 are not limited to magnetic sensors such as electromagnetic pickups, but may be optical sensors.
[0026]
As shown in FIG. 21, the crank rotor 38 has protrusions 38a, 38b, and 38c formed on the outer periphery thereof. The protrusions 38a, 38b, and 38c are connected to the cylinders (# 1, # 2, and # 3, # 3). 4) before compression top dead center (BTDC) θ1, θ2, θ3. In this embodiment, θ1 = 97 ° CA, θ2 = 65 ° CA, and θ3 = 10 ° CA.
[0027]
Each protrusion of the crank rotor 38 is detected by the crank angle sensor 39, and as shown in FIG. 19, crank pulses of BTDC 97 °, 65 °, and 10 ° are generated every 1/2 engine rotation (every 180 ° CA). Is output. Then, the input interval time of the crank position detection signal from the crank angle sensor 39 is timed by a timer, and the engine half rotation Hit The engine speed is calculated in terms of the elapsed time, i.e., half rotation time.
[0028]
The projection 38b serves as a reference crank angle for setting the ignition timing, and the projection 38c serves as a reference crank angle for the start-up injection start timing and a crank angle indicating the fixed ignition timing at the start-up.
[0029]
Further, as shown in FIG. 22, projections 40a, 40b, and 40c for cylinder discrimination are formed on the outer periphery of the cam rotor 40, and the projection 40a is after compression top dead center (ATDC) θ4 of the # 3 and # 4 cylinders. The protrusion 40b is formed of three protrusions, and the first protrusion is formed at the position of ATDCθ5 of the # 1 cylinder. Further, the protrusion 40c is formed by two protrusions, and the first protrusion is formed at the position of ATDCθ6 of the # 2 cylinder. In this embodiment, θ4 = 20 ° CA, θ5 = 5 ° CA, and θ6 = 20 ° CA.
[0030]
Then, when each projection of the cam rotor 40 is detected by the cam angle sensor 41 and the combustion stroke order of each cylinder is set to # 1 → # 3 → # 2 → # 4, this combustion stroke order and the cam angle sensor Cylinder discrimination is performed based on a pattern (see FIG. 19) with a value obtained by counting the cam pulses from 41 with a counter.
[0031]
On the other hand, the ECU 50 shown in FIG. 23 is composed mainly of two computers: a main computer 51 that performs fuel injection control, ignition timing control, and the like, and a dedicated sub-computer 52 that performs knock detection processing. A constant voltage circuit 53 for supplying a power source and various peripheral circuits are incorporated.
[0032]
The constant voltage circuit 53 is connected to a battery 55 via a relay contact of an ECU relay 54, and a relay coil of the ECU relay 54 is connected to the battery 55 via an ignition switch 56. The constant voltage circuit 53 is directly connected to the battery 55, and the fuel pump 29 is connected via a relay contact of the fuel pump relay 57.
[0033]
That is, the constant voltage circuit 53 supplies the control power when the ignition switch 56 is turned on and the relay contact of the ECU relay 54 is closed, and when the ignition switch 56 is turned off. Supply power for backup.
[0034]
The main computer 51 includes a CPU 58 (hereinafter referred to as a main CPU 58), a ROM 59, a RAM 60, and a backup RAM 61 that retains data by being supplied with backup power from the constant voltage circuit 53 even when the ignition switch 56 is turned off. The microcomputer includes a counter / timer group 62, a serial communication interface SCI 63, and an I / O interface 64 connected via a bus line 65.
[0035]
The counter / timer group 62 includes various counters such as a free-run counter, a cam angle sensor (hereinafter, abbreviated as “camsen” as appropriate) signal input counting counter, a fuel injection timer, an ignition timer, and a 0 described later. Various timers such as a periodic interrupt timer for generating a periodic interrupt every 5 ms, a crank angle sensor (hereinafter, abbreviated as “classane” as appropriate) signal input timing timer, and a watchdog timer for system abnormality monitoring The timers are generically referred to for convenience, and various other software counters / timers are used in the main computer 51.
[0036]
Similarly to the main computer 51, the sub computer 52 includes a CPU 71 (hereinafter referred to as sub CPU 71), a ROM 72, a RAM 73, a counter / timer group 74, an SCI 75, and an I / O interface 76 via a bus line 77. The main computer 51 and the sub computer 52 are connected to each other via a serial communication line via the SCIs 63 and 75.
[0037]
The I / O interface 64 of the main computer 51 includes, as input ports, an intake air amount sensor 32, a throttle opening sensor 33a, a water temperature sensor 36, an O2 sensor 37, an absolute pressure sensor 22, a vehicle speed sensor 42, and a battery 55. Are connected via an 8-channel input A / D converter 66, and an idle switch 33b, a crank angle sensor 39, and a cam angle sensor 41 are connected, and a starter switch for detecting a start state 43 is connected.
[0038]
In this embodiment, the A / D converter 66 uses inputs for seven channels, and the remaining one channel is reserved.
[0039]
An igniter 27 is connected to the output port of the I / O interface 64, and further, via the drive circuit 67, the ISCV 16, the injector 25, the relay coil of the fuel pump relay 57, and the duty for controlling the wastegate valve A solenoid valve 21 and an intake pipe pressure / atmospheric pressure switching solenoid valve 24 are connected.
[0040]
On the other hand, the I / O interface 76 of the sub-computer 52 is connected to the input port with a crank angle sensor 39 and a cam angle sensor 41, and knocks via an A / D converter 78, a frequency filter 79, and an amplifier 80. A sensor 34 is connected, and after the knock detection signal from the knock sensor 34 is amplified to a predetermined level by the amplifier 80, a necessary frequency component is extracted by the frequency filter 79, and the A / D converter 78 is extracted. Is converted into a digital signal and input.
[0041]
The main computer 51 processes detection signals from the sensors and calculates the fuel injection pulse width, ignition timing, and the like. That is, the intake air amount is calculated from the output signal of the intake air amount sensor 32, the fuel injection amount corresponding to the intake air amount is calculated based on various data stored in the RAM 60 and the backup RAM 61, the ignition timing, etc. Is calculated.
[0042]
A drive pulse width signal corresponding to the fuel injection amount is output to the injector 25 of the corresponding cylinder via the drive circuit 67 at a predetermined timing to inject fuel, and an ignition signal is sent to the igniter 27 at a predetermined timing. Is output to ignite the ignition plug 26a of the corresponding cylinder.
[0043]
As a result, the air-fuel mixture supplied to the corresponding cylinder explodes and burns, and the oxygen concentration in the exhaust gas is detected by the O2 sensor 37 facing the assembly portion of the exhaust manifold 9, and this detection signal is waveform-shaped. The main CPU 58 compares with the reference voltage (slice level) to determine whether the engine air-fuel ratio is on the rich side or the lean side with respect to the target air-fuel ratio, so that the air-fuel ratio becomes the target air-fuel ratio. Feedback controlled.
[0044]
On the other hand, the sub-computer 52 sets a sample section of the signal from the knock sensor 34 based on the engine speed and the engine load, and performs A / D conversion of the signal from the knock sensor 34 at a high speed in this sample section. The vibration waveform is faithfully converted into digital data, and the presence or absence of knocking is determined.
[0045]
The output port of the I / O interface 76 of the sub computer 52 is connected to the input port of the I / O interface 64 of the main computer 51, and the knock determination result at the sub computer 52 is sent to the I / O interface 76. Is output. When the determination result that knocking has occurred is output from the sub-computer 52, the main computer 51 reads knock data from the serial communication line via the SCI 63, and immediately determines the ignition timing of the corresponding cylinder based on the knock data. Delay and avoid knocks.
[0046]
In such engine control, the main computer 51 has various programs for each item such as signal input processing from each sensor, engine speed calculation, intake air amount calculation, fuel injection amount calculation, and ignition timing calculation. It is efficiently executed under the control of two OSs. This OS has various management functions for vehicle control and an internal strategy closely attached to this management function, and systematically combines various jobs.
[0047]
As the management function of the OS,
(1-1) Job priority processing
(1-2) Split file support for each job by section definition
(1-3) Stack usage monitoring function
(1-4) Abnormal interrupt operation monitoring function
(1-5) Standard map and standard work memory settings that do not create unique restrictions for each job
In addition to improving the development environment of the control strategy, the limited CPU capability can be maximized, and the equal time interval processing that is the basis of the digital control theory can be achieved as much as possible.
[0048]
Equal time interval processing is based on periodic interrupts every 0.5 ms, and five types of equal interval interrupt jobs are prepared every 2, 4, 10, 50, and 250 ms, and processing synchronized with engine rotation As an example, a high-priority classen job (hereinafter simply referred to as a classen job) that is immediately interrupted by crank angle signal input and an interrupt that is executed by crank angle signal input when there is no other job with a higher priority. A low-priority classen job with low urgency is available.
[0049]
Each of these jobs is given a priority level of 7 to 1 from the high side to the low side in the order of classel job> 2 ms job> 4 ms job> 10 ms job> low priority classen job> 50 ms job> 250 ms job. As shown in FIG. 12, the low-speed job is divided and processed for the high-speed job, and multiple wait processing for each job is performed.
[0050]
In addition, each program working under the OS is arranged in order for each function-specific management area, ie, a section area, and each section area is named by a section declaration for each function. The main section area used on each strategy file side is
○ Variable declaration area
○ Self-file name, automatic recording area when creating a file
○ Setting data area
○ Classen job area
○ 2ms job area
○ 4ms job area
○ 10ms job area
○ Low priority classen job area
○ 50ms job area
○ 250ms job area
○ Reset initialization job area
○ Initialization initialization job area
○ Background job area
○ Program body area
It is possible to develop a program by dividing a file for each function, and to make a structured description of the program possible.
[0051]
In addition, the above OS has an internal strategy closely related to the above management functions.
(2-1) A / D conversion processing
(2-2) Calculation of various information related to crank position
(2-3) Simulation function for debugging (engine rotation and A / D conversion)
(2-4) Setting the ignition timer
(2-5) Set fuel injection timer
In addition, various service routines related to these functions are prepared in each job.
[0052]
Conventionally, such a function has been achieved at each job level, but in this system, all the A / D conversion results, crank position information, and engine speeds prepared on the OS side and processed on the OS side are provided. Based on the above, when the fuel injection amount, the ignition timing, etc. are set in each job on the user side, these instruction values are set in the fuel injection timer and the ignition timer by the OS.
[0053]
Next, the job processing function in the main computer 51 will be described with reference to the flowcharts of FIGS. Since the sub computer 52 is a computer dedicated to knock detection processing, the description of its operation is omitted.
[0054]
First, when the ignition switch 56 is turned on and the system is powered on, a reset interrupt associated with the reset is started, various initializations are performed, and a periodic interrupt timer for starting a periodic interrupt every 0.5 ms is provided. It is started, and a classen interrupt that is started every time a signal is input from the crank angle sensor 39 (6 times per engine revolution for BTDC 97 °, 65 °, 10 ° CA) is permitted. Become.
[0055]
Then, on this background job, a 7-level job is preferentially processed by a periodic interrupt every 0.5 ms and a classen interrupt of 6 times per engine revolution. In these two interrupts, each process is executed and then jumped to a common address to execute the job priority process.
[0056]
The reset interrupt is also triggered by a factor that does not occur during normal operation, such as when division by zero is performed in an internal operation or when an infinite loop occurs.
[0057]
First, the periodic interruption every 0.5 ms shown in FIG. 2 will be described. In this periodic interrupt, the OS work area is set in step S100, the watchdog timer is initialized in step S101, the process proceeds to step S102, and the P-RUN flag is inverted once every 20 times, that is, every 10 ms. To do. The P-RUN flag is a flag for preventing the system from being automatically reset by a protection circuit (not shown). As long as the system operates normally and is reversed every predetermined time (every 10 ms), the above protection is performed. Circuit operation is blocked.
[0058]
Next, the process proceeds to step S103, and the switch output is transferred. This switch output is the ON / OFF value of the bit written in the memory in each job. Each job does not directly output to the output port of the I / O interface 64, and the OS side stores the memory every 0.5 ms. Transfer the value to the output port.
[0059]
In step S104, an A / D conversion subroutine is executed to make various settings related to A / D conversion. In step S105, a job flag creation subroutine is executed to execute 2, 4, 10, 50, After creating a job flag JB_FLG indicating each job interrupt request every 250 ms, A / D conversion is started in step S106.
[0060]
In the A / D conversion, basically, the 8-channel input of the A / D converter 66 is processed in a predetermined conversion order every 0.5 ms, and all inputs are converted in a cycle of 4 ms. However, one specific channel synchronizes every 90 ° crank angle (with a time accuracy of 0.5 ms) in order to A / D-convert the suction pipe pressure that generates rotational pulsation, and interrupts the conversion order. The process is performed in the form of an oval, and the subsequent input order is delayed by one.
[0061]
When the engine speed is 3750 rpm or higher, the last input in the A / D conversion is completely stopped, and when the engine speed is 7500 rpm or higher, the second input from the last is also stopped. Faster changes such as air temperature and intake air amount are set first, and cooling water temperature and voltage are set so that later changes are later, and the last A / D conversion order is set to crank synchronization input. Therefore, there is no particular problem.
[0062]
As shown in FIG. 13, the job flag JB_FLG is assigned with each bit of a 1-byte variable as a flag corresponding to each job, and a plurality of job requests can be made simultaneously. Bits 1 to 7 of this 1-byte variable correspond to priority levels 1 to 7, and are assigned to flags of 250 ms job, 50 ms job, low priority classen job, 10 ms job, 4 ms job, 2 ms job and classen job, respectively. Yes. When a predetermined bit is set, a corresponding job interrupt request with a priority level is made. Bit 0 is assigned to a background job flag and is not normally referred to.
[0063]
In step S105, the job flag JB_FLG is created by the job flag creation subroutine. After the A / D conversion is started in step S106, the process proceeds to step S107, and the bit corresponding to any job in the job flag JB_FLG is set. Find out if you are standing.
[0064]
As a result, when no bit of the job flag JB_FLG is set, there is no request from any job, the interrupt is terminated, and when any bit of the job flag JB_FLG is set, the process proceeds to step S108, It is checked whether or not there is a flag below the level (a state in which a job of a predetermined priority level is being executed when this periodic interrupt is executed).
[0065]
If there is no flag below the current level in step S108, the process jumps to the job priority processing of FIG. 4 indicated by the label WAR_JB. If there is a flag below the current level, the overlap of the level below the current level is found in step S109. Increase the counter OLC by one.
[0066]
The overlap counter OLC is a counter for storing job requests, and is assigned 1 byte for each priority level. The overlap counter OLC is incremented when a job is requested by the job flag JB_FLG and decremented when a job is completed. In other words, by storing job requests with a counter, it is possible to cope with multiple requests for jobs.
[0067]
Next, the process proceeds from step S109 to step S110 to check whether or not there is a flag higher than the current level. When there is no flag higher than the current level, the routine is terminated and the interrupt is terminated. , Jump to the job priority processing of the label WAR_JB.
[0068]
On the other hand, in contrast to the periodic interrupt every 0.5 ms, when the OS work area is set in step S200, the subroutine for calculating the crank position and half rotation time described later is executed in step S201. Then, a crank position variable for determining the current crank position and a half rotation time which is the sum of the latest three classane intervals are calculated.
[0069]
The crank position variable is a system variable prepared in the OS. As shown in FIG. 14, the crank positions for the cylinders # 1 to # 4 are divided into 12 states by 97 °, 65 °, and 10 ° CA. Represents the current crank position.
[0070]
That is, for each cylinder, a crank position information variable S_CCAS indicating the order of classane input with numerical values of 0, 1, 2 is assumed to be 0 for # 1, # 1 for cylinder # 2, 2 for cylinder # 2, and 3 for cylinder # 4. The current crank position is represented by three variables: a cylinder information variable S_RCAS indicating the combustion order of the cylinders, and an overall position variable S_ACAS that comprehensively represents the classene order and the cylinder order with numerical values of 0 to 11, and the crank position is confirmed. The crank position discriminating state is represented by an error level S_ECAS where 0 is a normal discriminating state, 1 is an inferred estimated state where the discriminating result is not consistent, and 2 is an unknown state. In FIG. 14, S_ indicating a system variable is omitted.
[0071]
Next, when the process proceeds from step S201 to step S202, the code stored in the accumulator A is read to determine whether the crank position determination is normally completed or cannot be determined in the crank position / half rotation time calculation subroutine. Check (error code 1, normal end code 0).
[0072]
In step S202, when the value of the accumulator A is 1 and the crank position cannot be determined, the interruption is terminated, and when the value of the accumulator A is 0 and the crank position is normally determined. In step S203, the engine stall flag is canceled.
[0073]
The engine stall flag is a flag indicating that the engine is in an engine stall state, and is set by an engine stall routine prepared for a 50 ms job when the time interval is 0.5 sec or more (approximately 30 rpm or less). The engine is cleared by this classene interrupt to cancel the engine stall state.
[0074]
Next, in step S204, an ignition timer setting subroutine is executed, and the ignition timer is set according to the ignition schedule created based on the ignition timing instruction value set on the user job side. This ignition schedule is a structure variable whose members are a dwell start time, a dwell on waiting time, a dwell off waiting time, and the like. A creation routine is prepared during a 10 ms job, and an ignition sequence is determined according to this ignition schedule.
[0075]
Next, in step S205, a fuel injection timer setting subroutine is executed, and the fuel injection start timing and the like are set in the fuel injection timer for the fuel injection amount instruction value (injection width for each cylinder) set on the user job side. Then, the process proceeds to step S206.
[0076]
In step S206, it is determined whether or not the current job level at which this classen is executed is the own job level. If the current job level is the classen job's own level, in steps S207 and S208, the classen job, low priority If the current job level is not the Krasen job level, whether or not the current job level is equal to or higher than the low-priority classen job level is determined in step S209. Check for no.
[0077]
When the current job level is equal to or higher than the low-priority class job, the process proceeds from step S209 to step S210. When the overlap counter OLC of the low-priority class job is incremented by 1, the job flag of the clasen job is displayed in step S211. And jump to the job priority processing of the label WAR_JB.
[0078]
On the other hand, if the current job level is not equal to or higher than the low-priority class job at step S209, the process proceeds from step S209 to step S212. When the job flag of the class job is set, the job flag of the low-priority class job is set at step S213. Set and jump to the job priority processing of the label WAR_JB.
[0079]
In this job priority process, when the job level JB_LEV, which is a 1-byte variable indicating the job priority level, is incremented by 1 in step S300, the process proceeds to step S301 to check whether a job flag corresponding to this priority level is set. . When the job flag is not set, the process returns to step S300 to further increase the job level JB_LEV by one. When the job flag is set, the process proceeds to step S302, and the overlap counter OLC of the job with the job flag is set. The initial value is changed from 0 to 1, and the process proceeds to step S303.
[0080]
In step S303, it is checked whether or not there is a higher job flag. When there is a higher job, the process returns to step S300 and the above processing is repeated, and when there is no higher job, the process proceeds to step S304. When the job execution flag JB_RUN is set, in step S305, the highest-level job is executed by a job execution subroutine described later.
[0081]
The job execution flag JB_RUN is a flag that is set at the start of job execution and cleared at the end of execution. By this flag, a job interrupted by a job having a higher priority is identified in the middle of processing. Can do.
[0082]
For example, as shown in FIG. 15, when a 10 ms job with JB_LEV = 4 is executed and an interrupt request for a 2 ms job with JB_LEV = 6 is made, the processing of the 10 ms job is interrupted, and the 2 ms job with a higher priority is JB_RUN = 1 and OLC = 1 are set and executed. If an interrupt request for a 4 ms job with JB_LEV = 5 occurs during the processing of this 2 ms job, the 4 ms job is accepted with JB_RUN = 0 and OLC = 1, but is not executed but is in a standby state. It becomes.
[0083]
Thereafter, when the job execution by the job execution subroutine is completed, the process proceeds from step S305 to step S306, the overlap counter OLC is decremented by 1, and it is checked in step S307 whether or not the overlap counter OLC has become zero. As a result, when the overlap counter OLC is not zero and there are multiple job interrupt requests at the same priority level, the process returns to step S305 to repeatedly execute the job, and when the overlap counter OLC becomes zero, Proceeding from step S307 to step S308, the job execution flag JB_RUN is cleared.
[0084]
Next, proceeding to step S309, when the job level JB_LEV is lowered by 1 and moved to the next job level, it is checked in step S310 whether the job level JB_LEV has become zero. When the job level JB_LEV is zero, this interrupt is terminated. When the job level JB_LEV is not zero, the process proceeds to step S311 to check whether or not the overlap counter OLC is zero.
[0085]
When the overlap counter OLC is zero in step S311, there is no job request at this level, so the process returns from step S311 to step S309, the job level JB_LEV is further lowered by 1 and the same processing is repeated, and the overlap is repeated. When the counter OLC is not zero, the process proceeds to step S312 to check whether or not the job execution flag JB_RUN is set at this job level.
[0086]
When the job execution flag JB_RUN is set in step S312, the job is being executed before the interruption, so the interruption is ended and the process returns to the job before the interruption, and the job execution flag JB_RUN must be set. For example, the process returns to step S304, the job at this level is executed, and the same processing is repeated.
[0087]
That is, in FIG. 15, when a 2 ms job with JB_LEV = 6 is completed and OLC = 0 and JB_RUN = 0, the job level is lowered by one, and a 4 ms job with JB_LEV = 5 becomes JB_RUN = 0, OLC = 1. From the standby state, JB_RUN = 1 is set and executed. Further, when the 4 ms job is completed, the process proceeds to JB_LEV = 4, and the processing of the 10 ms job suspended by the 2 ms job and the 4 ms job is resumed from the state of JB_RUN = 1 (during job execution).
[0088]
In this way, the job flag JB_FLG that informs the priority level and execution timing of each job is created using periodic interrupts and classene interrupts every 0.5 ms as the basic timing, so that it is possible to perform processing at equal intervals and engine rotation as accurately as possible. Synchronous processing is realized and each job can be processed efficiently. Furthermore, since the multiple request of the job is stored by the overlap counter OLC regardless of the job flag JB_FLG that is updated for each interrupt as the basic timing, the processing time of a certain job should be prolonged and the same job should be executed again. Even when the timing comes, it is possible to continue the process as much as possible without giving up the process halfway.
[0089]
Next, the job execution subroutine of FIGS. 5 to 8 will be described.
[0090]
First, in step S500, it is checked whether or not the job to be executed is a classen job by referring to the job flag JB_FLG. If it is not a classen job, the process branches to the label ALJ10. If it is a classen job, the process proceeds to step S501. Check whether or not there is a discrimination.
[0091]
When the cylinder discrimination is not performed, the routine is directly exited and the job is not executed. When the cylinder discrimination is performed, the process proceeds from step S501 to step S502, and the multiple wait state is made with reference to the value of the overlap counter OLC. It is examined whether or not.
[0092]
In the above step S502, when not in the multiple wait state, the process proceeds to step S503, and the system variable S_ACAS (crank total position variable) calculated for each classen interrupt is set as the user variable ACAS. Branch, the user variable ACAS is incremented by one and the remainder divided by 12 is taken as a new user variable ACAS, and this user variable ACAS is set to 0, 1, 2,..., 11, 0, 1,. Will be updated.
[0093]
That is, the classen job and the low-priority classen job may be delayed by being disturbed by the job or the high-priority job, but the classen interrupt is executed accurately in synchronization with the crank angle sensor signal, and the system variable S_ACAS is set in the job. Updated regardless of delay.
[0094]
Therefore, even if you know information related to the cylinder and crank position by referring to the system variable S_ACAS in the job and try to work according to this information, if you are delayed by other jobs, It becomes impossible to know information related to the cylinder and the crank position corresponding to his / her work. For this reason, in the case of a class request job and a low-priority class job, the system variable S_ACAS for OS is taken as a user variable ACAS when not in a multiple waiting state, and this user variable ACAS is updated every time a job is executed. In addition, information related to the cylinder and the crank position corresponding to itself is obtained so that proper processing is performed.
[0095]
Thereafter, the process proceeds from step S503 or step S504 to step S505. When the work area of the job is set, level zero interruption is permitted in step S506, and the process proceeds to the classen job section in step S507. Then, the processing linked to this classen job section is executed, and in step S508, interrupts are prohibited and the routine is exited.
[0096]
Next, in step S500, when the job to be executed is not a class job, it is checked in step S510 of label ALJ10 whether it is not a 2ms job. If it is a 2ms job, the work area of the job is set in step S511. In step S512, a zero level interrupt is permitted, and in step S513, the process moves to the 2 ms job section. Then, the job body (routine based on the control strategy on the user side or service routine prepared on the OS side) linked to this section is executed, and in step S514, the interrupt is prohibited and the routine is exited.
[0097]
On the other hand, if the job to be executed is not a 2 ms job in step S510, the process branches from step S510 to step S520 to check whether the job to be executed is a 4 ms job. If the job is not a 4 ms job, the process branches to the label ALJ30. If the job is a 4 ms job, the job work area is set in step S521, and the process proceeds to step S522. The 4 ms job is an A / D conversion use job, and uses A / D conversion data via a system shift buffer SSHB described later.
[0098]
In step S522, a zero level interrupt is permitted, and then in step S523, the switch input is read, and in step S524, the section moves to the 4 ms job to execute the linked job body. Thereafter, when exiting from the 4 ms job section, interrupt is prohibited in step S525, and the process proceeds to step S526 to shift the system shift buffer SSHB and exit the routine.
[0099]
As shown in FIG. 16, the system shift buffer SSHB includes each memory of head offset addresses 0, +8, +16, +24, +32, +34, +36, and +38 in which each A / D conversion result of 8 channels is stored. And 1 word of memory at the first offset address -2 address where the A / D conversion result of crank synchronization every 4 ms is stored, and one A / D conversion result executed every 0.5 ms is 1 word Stored at (2 bytes).
[0100]
From the first offset address 0, it is a four-stage shift memory, and the A / D conversion results for every 90 ° CA are stored, and the latest four data (one rotation) can be referred to from the job. The head offset addresses +32, +34, +36, and +38 are each one-word memory, and when the smoothing function is selected, a value obtained by weighted averaging of the A / D conversion results is stored to eliminate noise. The accuracy can be improved, and the data in these memories can be used for low-speed jobs.
[0101]
Also, from each head offset address +8, +16, +24, it is a memory of 4 words each and is used in a 4 ms job. Each of these memories stores the latest A / D conversion result from the beginning and stores it in the word after the overlap counter OLC value of the 4 ms job. When the 4 ms job is executed, the data is read from the beginning word and the job As the data ends, the data of each subsequent word is sequentially shifted to the word in the head direction, so that the FIFO buffer is read from the previously stored data.
[0102]
In other words, the A / D conversion is accurately performed at a cycle of 4 ms by a periodic interrupt every 0.5 ms, but the 4 ms job may be delayed due to a high priority job. Therefore, the FIFO buffer is used for A / D conversion delivery, and the data in each FIFO buffer is sequentially shifted in step S526 after referring to the data in each of the +8, +16, and +24 FIFO buffers in a 4 ms job.
[0103]
On the other hand, when the job to be executed is not a 4 ms job and branches to the label ALJ30 in step S520, it is checked in step S530 whether the job to be executed is a 10 ms job. If it is a 10 ms job, in step S531. If the work area of the job is set and level zero interruption is permitted in step S532, in step S533, the section moves to the 10 ms job, the job body is executed, and interruption is disabled in step S534 and the routine is exited.
[0104]
In the section of the 10 ms job, a service routine for calculating the engine speed from the half rotation time, a service routine for creating the ignition schedule described above, and the like are prepared on the OS side.
[0105]
If the job to be executed is not a 10 ms job in step S530, the process branches from step S530 to step S540 to check whether the job to be executed is a low-priority classen job. If it is not a low priority classen job, the process branches from step S540 to the label ALJ50. If the job to be executed is a low priority classen job, the process proceeds from step S540 to step S541. Check if there is any.
[0106]
When the current state is not the multiple wait state, the process proceeds from step S541 to step S542, and the system variable S_ACAS (crank total position variable) is set as the user variable ACAS, and the process proceeds to step S544. From step S543, the user variable ACAS is incremented by one, and the remainder obtained by dividing by 12 is taken. Then, the processing proceeds to step S544.
[0107]
In step S544, the job work area is set, and in step S545, level zero interrupts are enabled. In step S546, the section moves to the low-priority classen job section. After executing the job itself, interrupts are disabled in step S547. And exit the routine.
[0108]
Further, at label ALJ50, it is checked whether or not the job to be executed in step S550 is a 50 ms job. If the job is a 50 ms job, the process proceeds to step S551, the work area of the job is set, and the process proceeds to step S552.
[0109]
In step S552, if level zero interrupt is permitted, in step S553, the process moves to the 50 ms job section, and the engine prepared engine processing routine, cylinder specific ignition timing retard routine, fuel injection start timing setting routine, etc. are executed. In addition, a routine based on the control strategy on the user side is executed. Then, after completion of the job, interrupt is prohibited in step S554, and the routine is exited.
[0110]
On the other hand, when the job to be executed in step S550 is not a 50 ms job, the process branches from step S550 to step S560, and when the work area of the job is set, in step S561, a level zero interrupt is permitted, and the process proceeds to step S562. The process proceeds to the section area of the 250 ms job, and after executing the job body, interrupt is disabled in step S563 and the routine is exited.
[0111]
In the above-described job priority processing, it is necessary to accurately grasp the crank position at all times. For each classene interrupt, the crank position calculation subroutine shown in FIG. 1 is executed, and the crank position variables S_CCAS, S_RCAS, S_ACAS, S_ECAS is calculated, and a half rotation time is calculated. In the following description, S_ indicating a system variable is omitted from the crank position variable.
[0112]
In this crank position calculation subroutine, first, in step S600, the lower 2 bytes of the classene timer are stored in the lower 2 bytes of the soft timer. This classen timer is a hardware timer provided in the ECU 50. In this embodiment, the 16-bit timer can count up to 255 ms. However, a continuous area of 3 bytes is secured on the memory. 2 bytes of the classen timer are transferred to the byte, and the third byte is counted up by the interrupt generated by the overflow of the classen timer, and used as a soft timer.
[0113]
That is, when an overflow occurs in the classen timer, the overflow interrupt of FIG. 11 occurs, and when the third byte of the soft timer is incremented by 1 in step S900, the third byte of the soft timer exceeds 255 in step S901. Determine if there is any. If it does not exceed 255, the process jumps from step S901 to step S903. If it exceeds 255, the process proceeds from step S901 to step S902, the third byte of the soft timer is stopped at 255, and the process proceeds to step S903.
[0114]
In step S903, it is checked whether or not the third byte of the soft timer is not 2, that is, whether or not the classene interval exceeds 0.5 sec (255 ms × 2) and the engine is in the stalled state. When the third byte of the soft timer is not 2, the interrupt is terminated. When the third byte of the soft timer is 2, the process proceeds from step S903 to step S904 to check whether the engine flag is set.
[0115]
In step S904, the interrupt is terminated when the engine stall flag is set. When the engine stall flag is not set, the engine stall request flag for starting the engine stall routine prepared for the 50 ms job is set in step S905. End the interrupt.
[0116]
This makes it possible to count up to 64 seconds (255 ms x 256), and without using a special hardware timer of 16 bits or more, it is easy even when the time interval is very long, such as during cranking. Can respond.
[0117]
On the other hand, in the crank position calculation subroutine, when the process proceeds from step S600 to step S601, it is checked whether the classene interval is equal to or shorter than the set time. This set time is a time as a classen interval corresponding to the maximum engine speed, for example, 0.3 ms. If the classen interval is equal to or shorter than the set time in step S601, a step error is detected as a classen timer counting error due to noise contamination. In step S602, error code 1 is stored in the accumulator A. In step S601, if the classen interval is longer than the set time, the count of the classen timer is normal and the process proceeds to step S603.
[0118]
In step S603, a CCAS / RCAS determination subroutine, which will be described later, is executed to determine the crank position. In step S604, whether or not the error level ECAS is 2 is determined, i.e., at the time of cranking or the like. If ECAS = 2, the process branches to step S605 to store the error code 1 in the accumulator A, and exits the routine.
[0119]
On the other hand, if ECAS ≠ 2 in step S604, the process proceeds to step S606, where the third byte of the soft timer is set to zero. Then, the process proceeds to step S607 to check whether or not the crank position information variable CCAS is 1, that is, whether or not the current crank position is between BTDC 65 ° CA to 10 ° CA (see FIG. 14). When 1, the process jumps from step S607 to step S609. When CCAS ≠ 1, the process proceeds from step S607 to step S608, the A / D conversion request is incremented by 1, and the process proceeds to step S609.
[0120]
This A / D conversion request is a flag-like variable for instructing crank synchronous A / D conversion every 90 ° of crank angle, and takes a value of 0 or 1. When the value is 1, crank synchronous A / D Direct conversion. That is, as described above, of the 8 channels of A / D conversion, 1 channel of A / D conversion is performed every 90 ° of crank angle, but when CCAS becomes 0 (BTDC 97 °), CCAS is 2 When it becomes (BTDC 10 °), an A / D conversion request for crank synchronization is set, and the A / D conversion at every 90 ° of crank angle is interrupted with respect to the A / D conversion order every 0.5 ms. .
[0121]
Thereafter, in step S609, the total position variable ACAS is calculated by multiplying the cylinder information variable RCAS by 3 and adding the crank position information variable CCAS (ACAS = RCAS × 3 + CCAS). In step S610, the soft timer is set to 2 bytes. When the limit is reached and the classen timer overflows, the lower 2 bytes are set to FFFF (255 ms), and the process proceeds to step S611.
[0122]
In step S611, the classen interval data is stored in an array TCAS [ACAS] (element of the array) having the overall position variable ACAS = 0, 1, 2,... 11 as a subscript, and in step S612, the crank position information variable CCAS = Classane interval data is stored in an array MTCSX [CCAS] (element of the array) with subscripts 0, 1, and 2.
[0123]
As shown in FIG. 17A, the array TCAS is a 12-word classane interval table storing classane interval data for two engine revolutions corresponding to ACAS = 0, 1, 2,... As shown in FIG. 17B, MTCSX is a 3-word classen interval table in which 3 classen interval data corresponding to CCAS = 0, 1, and 2 are stored.
[0124]
That is, the information variables CCAS, RCAS, and ACAS are updated by the CCAS / RCAS determination subroutine (described later in detail) in step S603 and in step S609, for example, CCAS = 1, RCAS = 1, and ACAS = 4. Thus, when the crank position is BTDC 65 ° to 10 ° CA of the # 3 cylinder, from the clasen signal input at the BTDC 97 ° CA of the # 3 cylinder counted by the clasen mimer to the clasen signal input at the BTDC 65 ° CA of the # 3 cylinder The time (classane interval data) is stored at the address of ACAS = 3 in the array TCAS using the total position variable ACAS as a parameter in step S611, and the address of CCAS = 0 in the array MTCSX using the crank position information variable CCAS as a parameter in step S612. Store The
[0125]
Therefore, every time the overall position variable ACAS and the crank position information variable CCAS are updated every time a classene interrupt is input by the classene input, the data in the arrays TCAS and MTCSX are sequentially updated. By referring to the array TCAS, each cylinder It is possible to know the change in the distance between the clanes at each crank position (change in the rotational speed), to determine the presence or absence of misfire in each cylinder, the combustion state, etc., and to understand the operating conditions of all the cylinders. Further, by referring to the array MTCSX, the latest classene interval can always be obtained, and the current operation status can be quickly grasped.
[0126]
Next, when proceeding to step S613, the value of the error level ECAS is checked again. Here, since it has already been confirmed in step S604 that ECAS ≠ 2, whether or not the error level ECAS is 1 is checked, that is, whether or not the determination of the crank position is an estimated state that remains uneasy. .
[0127]
If ECAS ≠ 1 (ie, ECAS = 0) in step S613 and the crank position is determined with certainty, the process proceeds from step S613 to step S614, and the sum of the latest three classen interval data (in the array MTCSX). The sum of the stored classen interval data) is calculated as a 3-byte half rotation time MTCS18 (MTCS18 = ΣMTCSX).
[0128]
That is, the half rotation time MTCS18 is calculated every time the crank position information variable CCAS is updated for each classene interrupt and the data in the array MTCSX is updated, and the classen interval is set for each position of BTDC 97 °, 65 °, and 10 °. Since the latest data can always be obtained by taking the moving sum of, the engine speed and the like can be calculated based on the current driving situation, and more precise control becomes possible.
[0129]
On the other hand, when ECAS = 1 in the above step S613 and the estimation of the crank position remains uncertain, the half rotation time MTCS18 is not calculated from the array MTCSX, and the half rotation time estimation subroutine is executed in step S615. Then, the half rotation time MTCS18 is estimated.
[0130]
The estimation of the half rotation time MTCS 18 will be described. First, in step S700 of FIG. 9, it is checked whether or not the crank position information variable CCAS is 1, that is, whether or not the current crank position is between BTDC 65 ° and 10 °. When CCAS = 1, in step S701, from the angle 32 ° between BTDC 97 ° and 65 °, the previous classene interval × 180/32 is estimated as the half rotation time MTCS18 and the process returns.
[0131]
On the other hand, when CCAS is not equal to 1 in step S700, the process proceeds from step S700 to step S702 to determine whether or not the crank position information variable CCAS is 2, that is, the current crank position is BTDC 10 ° to ATDC 83 ° (next cylinder BTDC 97 °), and if CCAS ≠ 2 (CCAS = 0), the process proceeds to step S703, and the previous classene interval × 180 from the angle 93 ° between BTDC 10 ° and ATDC 83 °. / 93 is estimated as a half rotation time MTCS18 and the process returns. If CCAS = 2 in step S702, the process branches from step S702 to step S704, and the previous classene interval x 180/55 is estimated as the half rotation time MTCS18 from the angle 55 ° between BTDC 65 ° and 10 °. And return.
[0132]
In the crank position calculation subroutine, after calculating the half rotation time MTCS18 in step S614, or after estimating the half rotation time MTCS18 by the subroutine of step S615 described above, the process proceeds to step S616, and the half rotation of 3 bytes. When the time MTCS18 is limited to 2 bytes and stored in the predetermined variable MTCSK, the variable MTCSK is doubled and stored in the variable MTCSK4 in step S617, and the normal end code 0 is stored in the accumulator A in step S618. Exit the routine.
[0133]
Then, the engine speed is calculated every 10 ms in the above-described job execution subroutine, and this engine speed is calculated from the reciprocal of the variable MTCSK in which the 3-byte half-rotation time MTCS18 is limited to 2 bytes.
[0134]
Specifically, by dividing the time 30 sec, which is half the unit time (1 min) of the rpm per minute, by the half revolution time MTCSK, the variable NRPM in units of 1 rpm, that is, the engine speed is It is calculated (NRPM = 30 sec / MTCSK), and this engine speed is used as one of basic parameters for various control amount calculation processes.
[0135]
Next, the CCAS / RCAS discrimination subroutine shown in FIG. 10 will be described. In this subroutine, first, in step S800, the Camsen counter is limited to 0-4. The number of cam pulses from the cam angle sensor 41 (the number of cam pulses between Krasen signal inputs) counted by the camsen counter is 0 to 3 in the normal state as shown in FIG. Since there is a possibility of an abnormal count value of 4 or more due to influence, the Camsen counter is limited to 0 to 4 and the abnormal state is represented by 4.
[0136]
Next, the process proceeds to step S801, and a 5 × 4 × 2 combination (5 types of camsen counters 0 to 4 and cylinders) from the camsen counter (count value thereof), cylinder information variable RCAS, and crank position information variable CCAS. The cylinder / crank position state map CCHMAP in which the state data for the information variable RCAS is stored in four types of 0 to 3 and the crank position information variable CCAS is 0, 1 and 2 is read.
[0137]
As shown in FIGS. 18 (a) and 18 (b), this cylinder / crank position state map CCHMAP is obtained when the crank position information variable CCAS is 0 or 1, and when the crank position information variable RCAS is a change point of the cylinder position information variable RCAS. State data indicating whether normal or abnormal conditions should be determined or not should be estimated for all possible states of each combination of the Camsen counter and the cylinder information variable RCAS. You can evaluate the current state and know the next state to take.
[0138]
In other words, the program can be greatly simplified compared to the processing based on the normal condition judgment, the memory capacity can be saved, the processing speed can be improved, and the specification change can be flexibly dealt with. Can do.
[0139]
This status data is 2-bit data, which indicates whether it is fixed or estimated by the value of bit 0, and whether it is normal or abnormal by the value of bit 1. The value of bit 0 is fixed when 0 and indicates when 1 and as can be seen from FIG. 19, it is determined only when the Camsen counter is 2 or 3, and must be estimated otherwise. State. The value of bit 1 is normal when 0 and abnormal when 1 and is normal only when the Camsen counter is 3 or less and matches the combination shown in FIGS. 14 and 19, and otherwise. It is an abnormal condition.
[0140]
For example, the combination of CCAS = 0 or 1, ie, BTDC 97 ° to 10 ° of a certain cylinder, in which the Camsen counter is 0 and the cylinder information variable RCAS is 0, as can be seen from FIG. 14 and FIG. Since it is sufficient to estimate the position normally, state data of 01 (normal estimation) is stored in the corresponding area of the cylinder / crank position state map CCHMAP, and the camsen counter is 1 and the cylinder Since the combination in which the information variable RCAS is 0 is clearly abnormal and can only be estimated, state data of 11 (abnormality estimation) in binary is stored in the corresponding region of the cylinder / crank position state map CCHMAP. ing.
[0141]
Also, CCAS = 2, that is, a combination in which the camsen counter is 3 and the cylinder information variable RCAS is 0 with respect to BTDC 10 ° to ATDC 83 ° of a certain cylinder, is normally determined as the crank position sandwiching the TDC of the # 1 cylinder Therefore, 00 (normally determined) binary state data is stored in the corresponding area of the cylinder / crank position state map CCHMAP, and the camsen counter is 2 and the cylinder information variable RCAS is 0. Since there is obviously an abnormality, but there are two or more Camsen inputs, the state data of 10 (abnormal confirmation) is stored in the corresponding area of the cylinder / crank position state map CCHMAP. Yes.
[0142]
When the state data is read from the cylinder / crank position state map CCHMAP in step S801, the process proceeds to step S802, whether or not the error level ECAS is not 2, that is, an unknown state in which the current state is not discriminated. If ECAS = 2, it is checked in step S803 whether bit 0 of the state data read from the cylinder / crank position state map CCHMAP is 0, that is, whether it is a fixed state. If YES in step S804, the flow advances to step S804.
[0143]
On the other hand, when ECAS ≠ 2 in step S802, the process proceeds to step S804, where it is determined whether or not the estimated state is established, and the process proceeds to step S805 and subsequent processes or step S812 and subsequent processes depending on the determined state and estimated state. Further, when the process proceeds to step S804 in the confirmed state in step S803, the process proceeds to step S805 and subsequent steps.
[0144]
First, the processing after step S805 will be described. When the process proceeds to step S805, the cylinder is determined regardless of whether it is normal or abnormal. As can be seen from the time chart of FIG. Since the interrupt is an interrupt of BTDC 97 ° after three or two cam pulses are input, the crank position information variable CCAS is set to zero.
[0145]
Next, the process proceeds to step S806 to check whether the Camsen counter is 3 or not. When the Camsen counter is not 3, that is, when the Camsen counter is 2, it is after the ignition of the # 2 cylinder. The information variable RCAS is set to 3 and the process proceeds to step S809. When the Camsen counter is 3, since the # 1 cylinder is after ignition, the cylinder information variable RCAS is set to 1 in step S808 and the process proceeds to step S809.
[0146]
In step S809, state data is read again from the cylinder / crank position state map CCHMAP using the updated crank position information variable CCAS, cylinder information variable RCAS, and Camsen counter as parameters, and bit 1 of this state data is 1? That is, it is checked whether or not there is an abnormal state.
[0147]
As a result, when bit 1 of the state data is 1 and it is determined that the state is abnormal in step S809, it is determined that the update result of the crank position information variable CCAS and the cylinder information variable RCAS is an unreliable estimation, and an error level is determined in step S810. If ECAS is set to 1 and the routine is exited, and bit 1 of the status data is 0 and is normal, the error level ECAS is set to 0 in step S811 and the routine is exited.
[0148]
On the other hand, in the processing after step S812, whether or not the current crank position information variable CCAS (crank position information variable CCAS calculated in the previous classene interrupt) is 2, that is, the change point of the cylinder information variable RCAS, in step S812. If CCAS = 2, the flow advances from step S812 to step S813 to increase the cylinder information variable RCAS by 1. In step S814, the crank position information variable CCAS = 0 is set, and the flow advances to step S817.
[0149]
On the other hand, if CCAS ≠ 2 in step S812, the process proceeds from step S812 to step S815 to check whether the Camsen counter is not 0. If the Camsen counter is not 0, the process branches to the above-described Step S813. When the Camsen counter is 0, the crank position information variable CCAS is incremented by 1 in step S816, and the process proceeds to step S817.
[0150]
In step S817, using the updated crank position information variable CCAS, cylinder information variable RCAS, and Camsen counter as parameters, the state data is read again from the cylinder / crank position state map CCHMAP to check whether or not there is an abnormal state. When bit 1 of the data is 0 and is in a normal state, the routine is exited as it is (with the current error level ECAS = 0). If bit 1 of the status data is 1 and the status is abnormal in step S817, the process proceeds to step S818, and the error level ECAS is set on the assumption that the update results of the crank position information variable CCAS and cylinder information variable RCAS are uncertain. Set to 1 and exit the routine.
[0151]
【The invention's effect】
As described above, according to the invention described in claim 1, A crank pulse is output corresponding to a plurality of crank angle positions set in advance for each half rotation of the engine, and each time the crank pulse is input, the crank pulse input interval time since the previous crank pulse is input is measured. In addition, the crank pulse input interval time equal to the number of crank pulses input per half engine revolution including the time value is memorized over time, and these time values are added together. engine Half Since the time per revolution is calculated, the latest engine is always available without delay. Half The time value per revolution can be obtained, and the current driving situation can be quickly grasped by this time value. Half Data representing the engine operating status calculated using the time value per revolution is always obtained without delay as data indicating the current operating status, and this data enables more precise control based on the current operating status. Can do.
According to the invention of claim 2, the engine Half There is provided a table having the same number of crank pulses input per rotation and having an address associated with the crank position information for each crank pulse. And , Ku For each rank pulse input, the time from the previous crank pulse input to the current crank pulse input is stored in the corresponding address of the table. And add the time stored in each address of the table and engine Half Since the time per revolution is calculated, in addition to the effect of the invention of claim 1, the time between each crank pulse is calculated for each input of each crank pulse by a very simple process. Addition value Can be obtained and the calculation burden can be reduced.
[Brief description of the drawings]
FIG. 1 is a flowchart of a crank position calculation subroutine.
FIG. 2 is a flowchart of periodic interrupt processing every 0.5 ms.
FIG. 3 is a flowchart of classene interrupt processing.
FIG. 4 is a flowchart of job priority processing.
FIG. 5 is a partial flowchart 1 of a job execution subroutine.
FIG. 6 is a partial flowchart 2 of a job execution subroutine.
FIG. 7 is a partial flowchart 3 of a job execution subroutine.
FIG. 8 is a partial flowchart 4 of a job execution subroutine.
FIG. 9 is a flowchart of a half rotation time estimation subroutine.
FIG. 10 is a flowchart of a CCAS / RCAS discrimination subroutine.
FIG. 11 is a flowchart of an overflow interrupt process of a classen timer.
FIG. 12 is an explanatory diagram showing a job execution state
FIG. 13 is an explanatory diagram of a job flag.
FIG. 14 is an explanatory diagram of a crank position variable.
FIG. 15 is an explanatory diagram showing changes in a job execution flag and an overlap counter;
FIG. 16 is an explanatory diagram of a system shift buffer.
FIG. 17 is an explanatory diagram of a classene interval table.
FIG. 18 is an explanatory diagram of a cylinder / crank position state map.
FIG. 19 is a time chart showing crank positions and engine strokes.
FIG. 20 is a schematic configuration diagram of an engine system.
FIG. 21 is a front view of a crank rotor and a crank angle sensor.
FIG. 22 is a front view of a cam rotor and a cam angle sensor.
FIG. 23 is a circuit configuration diagram of an electronic control system.
[Explanation of symbols]
50 ECU
MTCSX Classen interval table
MTCS18 half rotation time
CCAS crank position information variable

Claims (2)

A crank pulse is output corresponding to a plurality of crank angle positions set in advance for each half rotation of the engine,
Each time the crank pulse is input, the crank pulse input interval time from the previous crank pulse input is measured, and the same number of crank pulse input intervals as the crank pulses input per half engine revolution including the time value are measured. over time storing time, rotation time calculation method for an engine and calculates the time per adds these time values engines a half rotation. A table having the same number of crank pulses input per half rotation of the engine and having an address associated with crank position information for each of the crank pulses,
For each crank pulse input, the time from the previous crank pulse input to the current crank pulse input is stored in the corresponding address in the above table,
2. The engine rotation time calculation method according to claim 1, wherein the time per half rotation of the engine is calculated by adding the time stored in each address of the table.

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