JPH08147185A - Emulator - Google Patents

Abstract

PURPOSE: To perform high-accuracy A/D conversion and D/A conversion without damaging the real-time property of emulation between the emulator and an application system with different operating voltages. CONSTITUTION: A voltage comparator circuit 10a at a correcting converting circuit 10 built in a slave microcomputer 4 digitally converts an operating voltage Vcc of the emulator and an analog system operating voltage AVcc of the application system, calculates how many times the operating voltage Vcc is in comparison with the analog system operating voltage AVcc, namely, calculates a Vcc/AVcc and stores that value in a correcting value storage register 10b. An analog signal ANn to be A/D converted is converted to a digital signal by an A/D converter 9 and outputted to a level correcting circuit 10c. The level correcting circuit 10c multiplies the relevant digital value with the Vcc/AVcc stored in the correcting value storage register 10b, level conversion is performed to the digital value of the operating voltage Vcc, and it is inputted to a CPU 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulator, which is a device for supporting the development of an application system using a microcomputer, and in particular, an analog / digital conversion (A / D conversion) or a digital operation in an application system having an operating voltage different from that of the emulator. The present invention relates to a technique effective when applied to analog / analog conversion (D / A conversion).

[0002]

2. Description of the Related Art According to a study by the present inventor, for example, in a so-called low-voltage emulator that supports an application system in which the operating voltage of the application system is lower than the operating voltage of the emulator, a so-called low voltage emulator is provided between the emulator and the application system. Input and output analog and digital signals A
When D / D conversion or D / A conversion is performed, an error occurs and it is difficult to perform emulation.

Therefore, even if the operating voltage of the emulator and the application system are different, in order to reduce the error due to A / D conversion and D / A conversion, the slave microcomputer (hereinafter referred to as slave microcomputer) in the emulator and the application system Address signals input to and output from
A user interface signal level conversion method that provides a conversion circuit that converts data signals and port analog signals into signals in a state corresponding to each operating voltage, and a slave microcomputer that operates at the same voltage as the operating voltage of the application system, that is, An emulator signal level conversion method is used in which a low-voltage operating slave microcomputer is provided in an emulator, and a conversion circuit converts an emulation signal related to emulation into a signal in a state corresponding to the operating voltage of the emulator.

First, in the case of the user interface signal level conversion system, as shown in FIG.
Is divided into an emulator unit (not shown) such as a portion supporting a CPU core of a microcomputer, and a target probe 30a such as a pseudo circuit of a peripheral device.

Further, the target probe 30a includes a slave microcomputer (hereinafter referred to as a slave microcomputer) 31 which substitutes the function of the target microcomputer, a control circuit 32 which realizes emulation and various debugging functions, and an emulation memory 3 which is a lending memory.
3 and the cable 34 to which the socket for the target microcomputer is connected, and the slave microcomputer 3
1 is connected to the emulator unit via the control bus CB.

Further, the slave microcomputer 31 contains an analog system module 31a for processing an analog voltage.

Also, this analog module 31a
As shown in FIG. 9, is an A / D converter 31 to which an analog system operating voltage AVcc, which is an operating voltage of the application system described later, and an analog signal ANn of the application system are input.
b is provided, the analog signal ANn is converted into a digital signal by the A / D converter 31b, and the data bus DB
CPU 31 that controls the slave microcomputer 31 via the
It is output to c.

Further, the A / D converter 31b and the CPU
The operating voltage Vcc of the emulator 30 is supplied to 31c.

Next, as shown in FIG. 8, the target probe 30a includes these slave microcomputer 31, control circuit 32, emulation memory 33 and cable 3.
4 is connected via an address bus 34a, a data bus 34b and a port system signal bus 34c.

The application system 35 under development by the user
A socket of a cable 34 is connected to the address bus 35a and data bus 35b in the application system 35.
The signals of the port-related signal bus 35c and the address-based signal bus 34a of the target probe 30a, the data bus 34b, and the port-related signal bus 34 are transmitted via the cable 34.
Input / output to / from c.

Here, the target probe 30a includes
A level conversion circuit 36 for converting the levels of signals on the address bus 34a, the data bus 34b, and the port system signal bus 34c is provided.
By this, the signal level is converted so that normal operation can be performed even when the operating voltages of the application system 35 and the emulator 30 are different.

For example, if the analog system operating voltage AVcc, which is the operating voltage of the application system 35, is 3V and the operating voltage Vcc of the emulator 30 is 5V, the maximum value of the analog voltage in the application system 35 is 3V.
The maximum value of analog signal ANn that is digitally converted is also 3V
Therefore, when A / D conversion is performed, an error occurs in the converted value.

Therefore, after all the signals on the address bus 34a, the data bus 34b and the port system signal bus 34c including the analog signal output from the application system 35 are level-converted by the level conversion circuit 36, 5V is applied.
Emulation is performed at different operating voltages by inputting to the operating slave microcomputer 31.

Therefore, all the signals input / output between the slave microcomputer 31 and the application system 35 via the cable 34 are input to the emulator 3 by the level conversion circuit 36.
The signal is converted into a signal corresponding to the operating voltage Vcc of 0.

Next, the emulator signal level conversion system will be described.

In this emulator signal level conversion method, as shown in FIG. 10, a slave microcomputer 31 that operates at the same voltage as the analog system operating voltage AVcc of the application system 35 is provided in the emulator 30.

As a result, the signal input / output between the slave microcomputer 31 and the application system 35 via the cable 34 is input without level conversion.

Here, the operating voltage Vcc of the emulator unit is the analog operating voltage AVc of the application system 35.
Since it is different from c, a level conversion circuit 36a for converting an emulation signal related to emulation is connected between the slave microcomputer 31 and the emulator unit via the control bus CB, and the control circuit 32, the emulation memory 33 and the slave microcomputer 31 are connected to each other. The level conversion circuit 36b is also connected between these via the address bus 34a and the data bus 34b.

For example, when the analog system operating voltage AVcc of the application system 35 is 3V and the operating voltage Vcc of the emulator 30 is 5V, the maximum voltage of the application system 35 and the slave microcomputer 31 is the same 3V, and A /
An error due to D conversion and D / A conversion does not occur.

Therefore, the operating voltage Vc of the emulator 30
Since c is 5 V, the level conversion circuits 36a and 36b convert an emulation signal related to emulation into a signal in a state corresponding to the operating voltage Vcc.

As a result, all signals input / output between the slave microcomputer 31 and the emulator unit / control circuit 32, emulation memory 33, etc. are emulated by the level conversion circuits 36a, 36b.
The signal is converted into a signal corresponding to the operating voltage Vcc of 0.

An example in which the emulator is described in detail is "Hitachi Microcomputer Technique" 1988 issued by Hitachi Microcomputer Engineering Co., Ltd.
Year Vol. 2 No. 2, there are P21 to P27.

[0023]

However, the present inventor has found that the emulator as described above has the following problems.

That is, in the user interface signal level conversion type emulator, since the signal to be A / D converted or D / A converted is stepped up or stepped down by the level conversion circuit, a conversion error occurs at that time, resulting in data conversion. The accuracy becomes poor and it becomes difficult to perform accurate emulation.

In the emulator of the emulator signal level conversion system, the operating voltage of the slave microcomputer is set to the same low voltage as the operating voltage of the application system, so that the operating speed of the slave microcomputer becomes low and the operation of the emulator is reduced. As the speed increases, the real-time property of emulation may be impaired.

An object of the present invention is to provide an emulator capable of performing highly accurate A / D conversion and D / A conversion without deteriorating the real-time property in emulation even if the operating voltage is different between the emulator and the application system. To provide.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0028]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

The emulator of the present invention converts an analog signal to be A / D converted into a signal in a state corresponding to the operating voltage of the emulator or D / D based on the comparison between the operating voltage of the application system and the operating voltage of the emulator. A correction conversion means for converting the A-converted digital signal into a digital signal in a state corresponding to the operating voltage of the applied system is provided.

In the emulator of the present invention, the correction conversion means is incorporated in a slave microcomputer that substitutes the function of the target microcomputer.

Further, in the emulator of the present invention, the correction conversion means calculates the correction value of how many times the operating voltage of the application system is the operating voltage of the emulator, and the voltage comparing means. And a first level conversion correction means for converting an analog signal or a digital signal based on the correction value stored in the storage register.

Further, in the emulator of the present invention, the correction conversion means is calculated by a voltage comparison means for calculating a correction value of how many times the operating voltage in the application system is the operating voltage of the emulator, and the voltage comparing means. A storage register for storing the correction value and a digital signal converted from an analog signal by an A / D conversion means provided in the slave microcomputer or a digital signal by a D / A conversion means provided in the slave microcomputer. It comprises a second level conversion correction means for converting the converted analog signal into a signal in a state corresponding to the operating voltage of the emulator or the application system.

Further, in the emulator of the present invention, the correction conversion means is an ISP (Inte) which is a programmable module built in a slave microcomputer.
11 sub-processor).

[0034]

According to the above-mentioned emulator of the present invention, the correction converting means makes the analog signal A / D converted based on the comparison between the operating voltage of the application system and the operating voltage of the emulator in a state corresponding to the operating voltage of the emulator. A digital signal that is converted to a digital signal or converted into a digital signal is converted into a signal in a state corresponding to the operating voltage of the application system, so that even if the operating voltage of the emulator and the application system are different, highly accurate A / D conversion is performed. And D / A conversion can be performed.

Further, according to the emulator of the present invention described above, the slave microcomputer which substitutes the function of the target microcomputer incorporates the correction conversion means, so that the number of components of the emulator is not increased and the cost is reduced and the accuracy is high. A / D conversion and D / A conversion can be realized.

Further, according to the above-mentioned emulator of the present invention, the voltage comparing means calculates the correction value of how many times the operating voltage of the application system is the operating voltage of the emulator, and the voltage comparing means calculates the correction value. The corrected value thus stored is stored, and the first level conversion correcting means converts the analog signal into an analog signal in a state corresponding to the operating voltage of the emulator or converts the digital signal based on the correction value stored in the storage register. Since the A / D conversion circuit or the D / A conversion circuit performs the signal conversion after the conversion to the digital signal in the state corresponding to the operating voltage of the application system, the highly accurate A / D conversion and D / A conversion can be performed. It can be carried out.

Further, according to the emulator of the present invention described above, the voltage comparison means calculates a correction value for the operating voltage of the application system to be several times the operating voltage of the emulator, and the storage register stores the correction value. , A second level conversion correcting means is provided in the slave microcomputer based on the correction value stored in the storage register A
The digital signal converted from the analog signal by the D / D conversion means or the analog signal converted from the digital signal by the D / A conversion means provided in the slave microcomputer is a signal corresponding to the operating voltage of the emulator or the application system. By converting to, it is possible to perform more accurate A / D conversion and D / A conversion.

Further, according to the above-mentioned emulator of the present invention, the correction conversion means is constituted by the ISP which is a programmable module built in the slave microcomputer, so that the ISP can perform the operation function of the correction conversion means by software. You can

[0039]

Embodiments of the present invention will now be described in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a connection diagram between an emulator and an application system according to Embodiment 1 of the present invention, and FIG.
1 is a block diagram of essential parts in a system configuration of an emulator according to a first embodiment of the present invention, and FIG. 3 is a block diagram of essential parts of a slave microcomputer provided with a correction conversion circuit according to a first embodiment of the present invention.

In the first embodiment, an application system 1 using a microcomputer under development by a user and a personal computer 2 which is a parent computer for software development.
An emulator 3 for debugging and evaluating software and hardware is connected between and.

In this embodiment, the analog system operating voltage AVcc which is the operating voltage of the application system 1 is 3V, and the operating voltage Vcc of the emulator is 5V.

Further, as shown in FIG. 2, the emulator 3 includes a portion A that supports the CPU core of the microcomputer.
It is divided into an emulator unit (not shown) that is not related to S (Application Specific) implementation and a target probe 3a that changes due to AS implementation such as a pseudo circuit of peripheral functions.

The emulator unit sets a master microcomputer that controls the emulator 3, a serial interface section that performs data communication with the personal computer 2 (shown in FIG. 1), execution of a program, and a trace stop condition. It consists of a breakpoint control unit that stops the program or trace when it is satisfied.

Further, the target probe 3a includes a slave microcomputer (hereinafter referred to as a slave microcomputer) 4 acting as a target microcomputer function, a control circuit 5 realizing emulation and various debugging functions, an emulation memory 6 as a lending memory, and An interface cable 7 to which a socket for the target microcomputer in the application system 1 is connected is provided.

Further, the socket of the interface cable 7 is connected to the application system 1, and signals transmitted through the address bus 1a, the data bus 1b and the port system signal bus 1c in the application system 1 are transmitted through the interface cable 7. Input / output to / from the target probe 3a.

Further, the analog system operating voltage AVcc in the application system 1 and the analog signal ANn for A / D conversion are also output to the target probe 3a via the interface cable 7.

Here, the target probe 3a is provided with a level conversion circuit 8 for performing signal level conversion, and the address bus 3b, data bus 3c and port system signal bus 3d of the target probe 3a are connected via the interface cable 7. The level conversion circuit 8 performs level conversion on each of the signals input to and output from.

The slave microcomputer 4 and the level conversion circuit 8 are connected via a port system signal bus 3d, and the slave microcomputer 4, the control circuit 5, the emulation memory 6 and the level conversion circuit 8 are connected to the address bus 3d.
b and the data bus 3c, respectively.

The address bus 3b, the data bus 3c of the target probe 3a and the control bus CB for inputting / outputting control signals are electrically connected to the emulator unit via a predetermined cable (not shown). .

The analog operating voltage AVcc and the analog signal ANn input via the interface cable 7 are also input to a predetermined input port of the analog module 4a built in the slave microcomputer 4.

This analog system module 4a has a structure shown in FIG.
As shown in FIG. 3, the A / D converter 9 for converting an analog signal into a digital signal and the analog signal ANn A / D-converted by the A / D converter 9 are digital in a state corresponding to the operating voltage Vcc of the emulator 3. A correction conversion circuit 10 for converting into a signal is provided.

Further, the correction conversion circuit 10 includes the analog system operating voltage AVcc of the application system 1 and the emulator 3.
Voltage comparison circuit 10a for comparing with the operating voltage Vcc of
A correction value storage register (storage register) 10b for storing the correction value comparatively corrected by the voltage comparison circuit 10a is provided.

Further, the correction conversion circuit 10 multiplies the digital signal converted from the analog signal by the A / D converter 9 by the correction value stored in the correction value storage register 10b, and the A / D converter 9 A level correction circuit (first level conversion correction means) 10c for correcting the digital signal converted by is provided.

The digital signal converted by the level correction circuit 10c is a CP that controls the slave microcomputer 4 via the data bus DB in the slave microcomputer 4.
Input to U4b.

Next, the operation of this embodiment will be described.

First, the operation voltage Vcc of the emulator 3 and the analog operation voltage AVcc of the application system 1 are input to the voltage comparison circuit 10a in the slave microcomputer 4.

The voltage comparison circuit 10a digitally converts the operating voltage Vcc and the analog operating voltage AVcc, and the operating voltage Vcc is converted to the analog operating voltage AVc.
Find how many times c. For example, the operating voltage Vcc is 5V and the analog system operating voltage AVcc is 3V.
If it is V, the operating voltage Vcc is the analog system operating voltage AV.
cc becomes 5/3 times, and its correction value, that is, 5/3
The value of is stored in the correction value storage register 10b.

Next, when the analog signal ANn is input to the A / D converter 9 of the slave microcomputer 4 through the interface cable 7, the A / D converter 9 receives the analog signal An.
After converting Nn into a digital signal, the level correction circuit 10
output to c.

When the digital signal converted by the A / D converter 9 is input to the level correction circuit 10c, the level correction circuit 10c converts the digital value into the value stored in the correction value storage register 10b, that is, 5/3 is multiplied, the level is converted into a digital signal in a state corresponding to the operating voltage Vcc of the emulator 3, and the digital signal is input to the CPU 4b.

Therefore, according to the first embodiment, even if the analog operating voltage AVcc of the application system 1 and the operating voltage Vcc of the emulator 3 are different, the analog signal A
By correcting Nn by the correction conversion circuit 10,
A highly accurate A / D conversion can be performed.

In the first embodiment, the level correction circuit 10c converts the analog signal ANn into a digital signal by the A / D converter 9, and then the correction value storage register 10 is operated by the level correction circuit 10c.
Although the correction was performed by multiplying the digital value based on the value stored in b, as shown in FIG. 4, the analog signal ANn is corrected to the level correction circuit (second level conversion correction means).
Alternatively, the analog signal ANn may be input to 10d, and the analog signal ANn may be multiplied by a correction value to be corrected, and then the analog signal ANn may be converted into a digital signal by the A / D converter 9.

As a result, after the analog signal ANn is corrected by analog, the A / D converter 9 performs A / D conversion.
Since the conversion is performed, more accurate A / D conversion can be performed.

In the first embodiment, the analog signal AN
Although the case where n is converted to a digital signal by the A / D converter 9 is described, the A / D converter 9 is not shown in the D /
By replacing it with an A converter, the digital signal output from the CPU 4b can be converted into a corrected analog signal ANn.

Further, the A / D converter 9 is not shown in FIG.
An analog signal A obtained by correcting the digital signal output from the CPU 4b and the analog signal ANn output from the application system 1 by substituting the D and D / A converters.
Nn as well as corrected digital signals can be converted.

(Embodiment 2) FIG. 5 is a block diagram of a main part of a slave microcomputer provided with a correction conversion circuit according to a second embodiment of the present invention.

In the second embodiment, the analog module 4a in the slave microcomputer 4 has a programmable module 4c such as an ISP built therein.

This programmable module 4c is a voltage comparison circuit 1 of the correction conversion circuit 10 in the first embodiment.
0a and the function of the level correction circuit 10c are given to the programmable module 4c by inputting a program in advance, and the software processing is performed by the voltage comparison function unit 4d and the level correction function unit (first level conversion correction means) 4e. .

The value comparatively corrected by the voltage comparison function unit 4d is stored in the register (storage register) 4f provided in the programmable module 4c.

The operating voltage Vcc of the emulator (not shown) and the operating voltage AVcc of the applied system (not shown) are supplied to the voltage comparison function section 4d of the programmable module 4c provided in the analog system module 4a. When input, the voltage comparison function unit 4d softly finds how many times the operating voltage Vcc is higher than the analog operating voltage AVcc based on the input program.

For example, if the operating voltage Vcc is 5V,
When the analog system operating voltage AVcc is 3V, the operating voltage Vcc becomes 5/3 times the analog system operating voltage AVcc, and its correction value, that is, the value of 5/3 is registered in the register 4f.
Stored in.

When the analog signal ANn is input to the A / D converter 9 of the slave microcomputer 4, the A / D converter 9 converts the analog signal ANn into a digital signal and then outputs it to the level correction function unit 4e. To do.

When the digital signal converted by the A / D converter 9 is input to the level correction function unit 4e, the level correction function unit 4e causes the register 4 to operate based on the program.
The correction value stored in f is multiplied by the digital signal to perform level conversion on the digital signal in a state corresponding to the operating voltage Vcc, and then the digital signal is input to the CPU 4b.

As a result, in the second embodiment, even if the analog system operating voltage AVcc of the application system and the operating voltage Vcc of the emulator are different, the analog signal ANn is corrected by the programmable module 4c so that a high precision A / A can be obtained. D conversion can be performed.

Further, according to the second embodiment, since the operation function of the programmable module 4c can be easily changed by software, it is possible to flexibly cope with design changes and the like.

In the second embodiment, the analog signal ANn is converted into a digital signal by the A / D converter 9, and then the programmable module 4c multiplies the digital value by the value stored in the register 4f. Although the correction was performed, as shown in FIG. 6, the analog signal ANn is input to the level correction function unit (second level conversion correction means) 4g, and the analog signal ANn is multiplied by the correction value to perform the correction. You may make it convert into a digital signal by the A / D converter 9 later.

As a result, after the analog signal ANn is corrected by analog, the A / D converter 9 performs A / D conversion.
Since the conversion is performed, more accurate A / D conversion can be performed.

Also in the second embodiment, the analog signal AN
Although the case where n is converted to a digital signal by the A / D converter 9 is described, the A / D converter 9 is not shown in the D /
By replacing it with an A converter, the digital signal output from the CPU 4b can be converted into a corrected analog signal ANn.

Furthermore, the A / D converter 9 is not shown in FIG.
An analog signal A obtained by correcting the digital signal output from the CPU 4b and the analog signal ANn output from the application system 1 by substituting the D and D / A converters.
Nn as well as corrected digital signals can be converted.

(Embodiment 3) FIG. 7 is a block diagram showing a main configuration of an emulator provided with a correction conversion circuit according to Embodiment 3 of the present invention.

In the third embodiment, the correction conversion circuit 10 is provided in the target probe 3a of the emulator 3.

Further, the correction conversion circuit 10 includes a voltage comparison circuit 10a for comparing the analog operation voltage AVcc which is the operation voltage of the application system 1 with the operation voltage Vcc of the emulator 3, and the comparison and correction by the voltage comparison circuit 10a. Correction value storage register (storage register) that stores the adjusted value
10b and the analog signal ANn based on the values stored in the correction value storage register 10b.
It is composed of a level correction circuit (second level conversion correction means) 10d which performs conversion by multiplying n.

Then, the analog system operating voltage A output from the application system 1 via the interface cable 7
Vcc and the operating voltage Vcc of the emulator 3 are input to the voltage comparison circuit 10a, and the analog signal ANn is input to the level correction circuit 10d.

The output signal of the level correction circuit 10d is connected so as to be input to an A / D converter (not shown) in the analog system module 4a built in the slave microcomputer 4.

Next, the operation of this embodiment will be described.

First, in the voltage comparison circuit 10a in the correction conversion circuit 10 provided in the target probe 3a,
Operating voltage Vcc of emulator 3 and application system 1
The analog operation voltage AVcc of is input.

Then, the voltage comparison circuit 10a digitally converts the operating voltage Vcc and the analog operating voltage AVcc, and the operating voltage Vcc is converted to the analog operating voltage AVc.
Find how many times c. For example, the operating voltage Vcc is 5V and the analog system operating voltage AVcc is 3V.
If it is V, the operating voltage Vcc is the analog system operating voltage AV.
It becomes 5/3 times cc.

Next, the correction value obtained by the voltage comparison circuit 10a, that is, the value of 5/3 is stored in the correction value storage register 10b.

When the analog signal ANn is input to the level correction circuit 10d via the interface cable 7, the level correction circuit 10d outputs the analog signal ANn as the correction value 5 / which is the correction value stored in the correction value storage register 10b. 3 is multiplied by the analog signal ANn, and A of the analog system module 4a built in the slave microcomputer 4
The analog signal ANn is input to the / D converter, converted into a digital signal in a state corresponding to the operating voltage Vcc of the emulator 3, and input to the CPU (not shown).

Therefore, according to the third embodiment, by providing the correction conversion circuit 10 on the target probe 3a, even if the correction conversion circuit 10 cannot be provided in the slave microcomputer 4 due to a problem such as a chip area space. It is possible to perform highly accurate A / D conversion.

Further, since the A / D conversion is performed by the A / D converter after the analog signal ANn is corrected, the higher precision A / D conversion can be performed. Although the present invention has been specifically described based on the embodiment, it goes without saying that the present invention is not limited to the embodiment and various modifications can be made without departing from the scope of the invention.

[0092]

The effects obtained by the typical ones of the inventions disclosed in this application will be briefly described as follows.
It is as follows.

(1) According to the present invention, the correction conversion means converts an analog signal or a digital signal into a signal in a state corresponding to the operating voltage of the emulator or the applied system even when the operating voltage of the emulator and the applied system are different. Therefore, highly accurate analog / digital conversion and digital / analog conversion can be performed.

(2) Further, in the present invention, by incorporating the correction conversion means in the slave microcomputer, the analog / digital conversion and the digital / analog conversion can be performed at a low cost and with high accuracy without increasing the number of components of the emulator. realizable.

(3) Further, in the present invention, the digital signal or the analog signal converted by the analog / digital conversion means or the digital / analog conversion means provided in the slave microcomputer is converted into the second signal.
By converting the level conversion correcting means into a signal in a state corresponding to the operating voltage of the emulator or the applied system, more accurate analog / digital conversion and digital / analog conversion can be performed.

(4) According to the present invention, the correction conversion means is an ISP built in the slave microcomputer.
With this configuration, highly accurate analog / digital conversion and digital / analog conversion can be easily performed.

(5) Further, in the present invention, the above (1) to
According to (4), even if the operating voltage of the emulator and the application system are different, accurate emulation can be easily performed without lowering the operating speed of the slave microcomputer.

[Brief description of drawings]

FIG. 1 is a connection diagram between an emulator and an application system according to a first embodiment of the present invention.

FIG. 2 is a block diagram of essential parts in the system configuration of the emulator according to the first embodiment of the present invention.

FIG. 3 is a block diagram of a main configuration of a slave microcomputer provided with a correction conversion circuit according to the first embodiment of the present invention.

FIG. 4 is a block diagram of a main part of a slave microcomputer provided with a correction conversion circuit according to another embodiment of the present invention.

FIG. 5 is a block diagram of a main part configuration of a slave microcomputer provided with a correction conversion circuit according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a main part configuration of a slave microcomputer provided with a correction conversion circuit according to still another embodiment of the present invention.

FIG. 7 is a block diagram of a main part in a system configuration of an emulator according to a third embodiment of the present invention.

FIG. 8 is a block diagram of a main part in a system configuration of an emulator studied by the present inventor.

FIG. 9 is a block diagram of a main part of a slave microcomputer examined by the present inventor.

FIG. 10 is a block diagram of essential parts in a system configuration of an emulator examined by the present inventor.

[Explanation of symbols]

 1 Application system 1a Address bus 1b Data bus 1c Port system signal bus 2 Personal computer 3 Emulator 3a Target probe 3b Address bus 3c Data bus 3d Port system signal bus 4 Slave microcomputer 4a Analog system module 4b CPU 4c Programmable module 4d Voltage comparison function Section 4e level correction function section (first level conversion means) 4f register 4g level correction function section (second level conversion correction means) 5 control circuit 6 emulation memory 7 interface cable 8 level conversion circuit 9 A / D converter 10 Correction conversion circuit (correction conversion means) 10a Voltage comparison circuit (voltage comparison means) 10b Correction value storage register (storage register) 10c Level correction circuit (first level conversion means) 10 Level correction circuit (second level conversion means) Vcc operating voltage AVcc analog system operating voltage ANn analog signal CB control bus 30 emulator 30a target probe 31 slave microcomputer 31a analog system module 31b A / D converter 31c CPU 32 control circuit 33 Emulation memory 34 Cable 34a Address bus 34b Data bus 34c Port system signal bus 35 Application system 35a Address bus 35b Data bus 35c Port system signal bus 36 Level conversion circuit 36a Level conversion circuit 36b Level conversion circuit CB Control bus DB data bus Vcc Operating voltage AVcc analog operating voltage ANn analog signal

Claims (5)

[Claims] 1. An emulator for emulating an application system using a microcomputer under development different from the operating voltage of the emulator, wherein the analog / analog based on a comparison between the operating voltage of the application system and the operating voltage of the emulator. Compensation conversion means for converting an analog signal to be digitally converted into a signal in a state corresponding to the operating voltage of the emulator or a digital signal to be digital / analog converted into a signal in a state corresponding to the operating voltage of the applied system is provided. An emulator characterized by that. 2. The emulator according to claim 1, wherein the correction conversion means is built in a slave microcomputer which substitutes the function of the target microcomputer. 3. The voltage conversion means, wherein the correction conversion means calculates a correction value of how many times the operating voltage of the application system is the operating voltage of the emulator, and the correction value calculated by the voltage comparing means. A storage register for storing
A first analog-digital conversion means or a digital-analog conversion means provided in the slave microcomputer for converting the analog signal or the digital signal based on a correction value stored in the storage register; 3. The emulator according to claim 1, wherein the emulator comprises the level conversion correcting means. 4. The voltage conversion means, wherein the correction conversion means calculates a correction value of how many times the operating voltage in the applied system is the operating voltage of the emulator, and the correction value calculated by the voltage comparing means. And a digital signal converted from the analog signal by the analog / digital conversion means provided in the slave microcomputer or the digital signal by the digital / analog conversion means provided in the slave microcomputer. 3. The emulator according to claim 1, further comprising a second level conversion correction means for converting an analog signal converted from the above. 5. The emulator according to claim 2, 3 or 4, wherein the correction conversion means is constituted by an ISP which is a programmable module built in the slave microcomputer.