RU120255U1 - PROGRAMMER OF PIC-MICROCONTROLLERS WITH ADJUSTABLE OVERLOAD PROTECTION - Google Patents

Abstract

PIC microcontroller programmer with adjustable overload protection, containing three panels for installing DIP-18, DIP-28 and DIP-40 microcontrollers, in which ceramic blocking capacitors are installed between the Vss and Vdd pins, a COM port for connecting to a computer, a rectifier with sequential voltage doubling and stabilization with two electrolytic and two blocking ceramic capacitors, which is powered by the clock pulses of the COM port, a transistor in the key mode with protective diodes in the MCLR output circuit for supplying programming voltage to the microcontroller, a switch on the transistor that supplies programming signals with COM -port to the OSI pin (PGD) of the microcontroller and checking the programming results at the OSO pin (PGC), a transistor voltage regulator for setting the operating voltage of programming at the MCLR pin of the microcontroller, characterized in that the model includes an adjustable output protection device failure of programmable PIC microcontrollers in non-standard situations, consisting of a low-power thyristor, a limiting resistor, a measuring trimming resistor and a normally open reset button.

Description

The utility model relates to the field of microprocessor and microcontroller circuitry, in particular to programming devices for FLASH program memory and EEPROM data memory of modern eight-bit PIC microcontrollers from Microship.

Known analogue - Patent for utility model No. 72805 of the Russian Federation. Bull. No.12 of 04/27/2008 “Programmer of program memory FLASH and data memory EEPROM of microcontrollers from MICROCHIP” Akinshin RN, Ankudinov K.A., Ankudinov A.I. etc. An analogue (see Appendix 1 - an analogue) includes: DIP-18, DIP-28 and DIP-40 panels with three ceramic blocking capacitors for installing PIC microcontrollers of middle and older generations PIC16F83, PIC16F84, PIC16F84A, PIC16F627, PIC16F628, PIC16F873, PIC16F873A, PIC16F874, PIC16F874A, PIC16F876, PIC16F876A, PIC16F877, PIC16F877A, PIC18F242, PIC18F252, PIC18F442, PIC18F452, etc. COM port for connecting to a computer; a rectifier with sequential doubling and voltage stabilization with two electrolytic and two blocking ceramic capacitors, which is fed by the clock pulses of the COM port; a key-mode transistor with protective diodes in the MCLR programming output circuit to supply programming voltage to the PIC microcontroller; a transistor switch that supplies programming signals from the COM port to the OSI pin (PGD) of the microcontroller and checks the programming results from the OSO pin (PGC); transistor voltage regulator for setting the operating voltage of programming 12-13.5 V at the output of the MCLR of the PIC microcontroller.

The analogue has the following disadvantages:

1. When installing in the DIP-18, DIP-28 and DIP-40 panels, a PIC microcontroller with a 180-degree turn (from the correct position, an emergency (non-standard) situation occurs when the high programming potential of 12-13.5 V is not supplied to the high-voltage programming the MCLR input of the PIC microcontroller, or it can go to any of the outputs of the microcontroller, which are designed to supply voltages of up to 5 V. This situation is non-standard (emergency) and leads to loss of operation of the PIC microcontroller.

2. During normal installation of PIC microcontrollers in the DIP panel, but an unreliable contact or its absence at all between the same contacts V _ss and V _{dd of the} PIC microcontroller in the DIP panel of the programmer, respectively, and this non-standard situation in some cases also leads to exit out of order programmable PIC microcontrollers.

Known prototype - Patent for utility model No. 84,175 of the Russian Federation. Bull. No. 18 dated 06/27/2009 “Programmer of FLASH- and EEPROM-memory of PIC microcontrollers” Rumyantsev V.L., Akinshin ON, Ankudinov K.A. etc. The prototype (see Appendix 2 for the prototype) includes: DIP-18, DIP-28 and DIP-40 panels with three ceramic blocking capacitors for installing PIC microcontrollers of middle and older generations PIC16F83, PIC16F84, PIC16F84A, PIC16F627, PIC16F628, PIC16F873, PIC16F873A, PIC16F874, PIC16F874A, PIC16F876, PIC16F876A, PIC16F877, PIC16F877A, PIC18F242, PIC18F252, PIC18F442, PIC18F452, etc. COM port for connecting to a computer; a rectifier with sequential doubling and voltage stabilization with two electrolytic and two blocking ceramic capacitors, which is fed by the clock pulses of the COM port; a key-mode transistor with protective diodes in the MCLR programming output circuit to supply programming voltage to the PIC microcontroller; a transistor switch that supplies programming signals from the COM port to the OSI pin (PGD) of the microcontroller and checks the programming results from the OSO pin (PGC); transistor voltage regulator for setting the operating voltage of programming 12-13.5 V at the output of the MCLR of the PIC microcontroller; a device for protection against failure of programmable PIC microcontrollers in non-standard situations, consisting of a ballast resistor, a reference diode and a control transistor.

The prototype has the following main disadvantage:

The programming experience of a large series of PIC microcontrollers showed that in case of unusual situations in the prototype, the programmer's protective device, consisting of a ballast resistor, a reference diode, and a regulating transistor, reacts to a state close to a short circuit in the PIC microcontroller programming circuit: MCLR output (12 -13.5 B) - microcontroller structure - output V _ss (0 volts) and the speed regulating transistor protection device has a finite value, however in a sufficiently large number of cases fuss Novena to unusual situations, as the practice - an essential part of the PIC-microcontroller manages to fail.

Thus, in the event of unusual situations, the disadvantages of the analogue also appear in the prototype only with a lower probability of their occurrence.

The proposed utility model solves the problem of improving the reliability of maintaining the operability of programmable PIC microcontrollers of the middle generation PIC16F83, PIC16F84, PIC16F84A, PIC16F627, PIC16F628, PIC16F873, PIC16F873A, PIC16F874, PIC16F874A, PIC16F8168, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8768, PIC16F8168, PIC16F8168, PIC16F8168, PIC16F8168, PIC16F8168, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876, PIC16F876. older generation microcontrollers PIC18F242, PIC18F242A, PIC18F252, PIC18F252A, PIC18F442, PIC18F442A, PIC18F452, PIC18F452A, etc. in non-standard situations:

1. If the PIC microcontrollers are incorrectly installed in the DIP-18, DIP-28 and DIP-40 programming panels with a 180-turn turn (from the normal location;

2. During normal installation of microcontrollers in the DIP panel, but an unreliable contact or its absence at all between the same contacts V _ss and V _{dd of the} PIC microcontroller in the DIP panel of the programmer, respectively.

The task is achieved by the fact that in the programmer of PIC microcontrollers with adjustable overload protection, containing three panels for installing microcontrollers DIP-18, DIP-28 and DIP-40, in which ceramic blocking capacitors, COM are installed between the terminals V _ss and V _dd - port for connecting to a computer, a rectifier with sequential doubling and voltage stabilization with two electrolytic and two blocking ceramic capacitors, which is fed by the clock pulses of the COM port, the transistor in key mode with protective diodes in the MCLR output circuit for supplying programming voltage to the microcontroller, a switch on the transistor, which supplies programming signals from the COM port to the OSI (PGD) terminal of the microcontroller and verifies the programming results on the OSO (PGC) terminal, a transistor voltage regulator for setting the working programming voltage at the MCLR pin of the microcontroller, a device for adjustable protection against failure of programmable PIC microcontrollers in non-standard situations, consisting of s low-power thyristor, limiting resistor, measuring trimmer and normally open reset button.

By eliminating from the prototype a protection device consisting of a ballast resistor, a reference diode, and a regulating transistor, and introducing into the utility model a device for adjustable protection against failure of programmable PIC microcontrollers in non-standard situations, consisting of a low-power thyristor, a limiting resistor, a measuring trimmer and normally open reset button, it is possible to regulate the protection current of PIC microcontrollers, which made it possible to obtain the following Results:

1. At the onset of the first non-standard situation, installation of PIC microcontrollers in the DIP panel of the programmer with a 180-degree turn (from the normal location always, the microcontroller remains operational by limiting the current through the PIC microcontroller to the maximum permissible level.

2. When the second non-standard situation arises - an unreliable contact or its absence at all between the same contacts V _ss and V _{dd of the} PIC microcontroller and the DIP panel of the programmer, the microcontroller also remains operational by limiting the programming current through the PIC microcontroller to the maximum permissible level.

Thus, as a result of the measures taken, the utility model makes it possible to maintain the operability of the middle-generation programmable PIC microcontrollers PIC16F83, PIC16F84, PIC16F84A, PIC16F627, PIC16F628, PIC16F873, PIC16F873A, PIC16F874, PIC16F874A, PIC16F877, PIC16F8778, PIC16F8778, PIC16F8778, PIC16F877, PIC16F877, PIC16F877, PIC16F877, PIC16F877, PIC16F877, PIC16F877. also PIC microcontrollers of the older generation PIC18F242, PIC18F242A, PIC18F252, PIC18F252A, PIC18F442, PIC18F442A, PIC18F452, PIC18F452A, etc. in the event of unusual situations due to the possibility of regulating the protection current of the programmer.

In FIG. shows a circuit diagram of a device - utility model - "Programmer of PIC microcontrollers with adjustable overload protection."

The programmer of PIC microcontrollers with adjustable overload protection (see Fig.) Includes: COM port (DB9F) 1 with TXD, SG, CTS, DTR and RTS pins; rectifier with sequential doubling and voltage stabilization on diodes 2 and 3 (KD522B), zener diode 4 (KS156A with U _ST = 5.0-5.5 V at I _ST = 20 mA), zener diode 5 (KS406B without parameter selection), electrolytic filter capacitors 6 and 7 (47 and 220 μF), respectively, blocking ceramic capacitors 8 and 9 (0.1 μF); voltage regulator on transistor 10 (KT3102B), trimmer resistor 11 (3.3 kOhm), resistor 12 (10 kOhm) and electrolytic capacitor 13 (100 μF), which provides the setting interval voltage 12.0-13.5 V at the MCLR pin programmable microcontrollers; a key mode transistor 14 (КТ3102Б) with protective diodes 15 and 16 (КД522Б), which supplies power to the MCLR pin of programmable microcontrollers; DIP-18 17, DIP-28 18 and DIP-40 19 panels for installation of programmable microcontrollers, in which the outputs of one functional purpose are combined, since only one microcontroller is programmed at a time, and only power _sockets V _ss are shown on panels 17, 18 and 19 and V _dd , shunted by blocking ceramic capacitors 20, 21 and 22 (0.1 μF) and MCLR, PGC (OCO), PGD (OCI) programming leads; an electronic switch on transistor 23 (KT3102B) with resistors 24 (10 kOhm) and 25 (1.5 kOhm), switching the programming signals of the microcontrollers and checking the programming results passing through the COM port 1 from the computer and back to it; a device for adjustable protection against failure of programmable PIC microcontrollers, consisting of a low-power thyristor 26 (2U101B with a permissible forward current of 75 mA, a turn-on time of 10 μs, a release voltage of about 100 mV, a permissible reverse voltage of 50 V), a limiting resistor 27 (3, 3 kOhm), measuring trimmer 28 (1 ohm) and normally open reset button 29.

The PIC microcontroller programmer with adjustable overload protection (see Fig.) Can work in standard (working) and non-standard (emergency) programming modes of PIC microcontrollers:

1. The standard programming mode (see Fig.) Is the operating mode for programming microcontrollers, in which the microcontroller to be programmed is inserted into the corresponding panel of the programmer 17, 18 or 19, the COM port 1 of the programmer is connected to a computer on which one of the known programs controlling the programmer (for example, the IC-Prog control program, which can be found on the website http://www.ic-prog.com). Next, the HEX file of the microcontroller operation algorithm obtained by any of the known methods is entered into the control program. Then the control program sends signals to the COM port 1 of the programmer and the latter works as follows: the rectifier starts to work with sequential multiplication and voltage stabilization on the elements 2-9; 5.0-5.5 V power is supplied to the terminals of the programmable microcontroller V _ss and V _dd ; the voltage regulator on the elements 10-13 supplies a voltage of 12.0-13.5 V to the transistor switch on the elements 14-16; when a TXD signal is supplied from COM port 1, the transistor switch on elements 14-16 supplies programming power to the MCLR pin of the microcontroller, which is now ready to directly write to it the HEX file of the microcontroller operation algorithm; according to the control program signals from the computer through the COM port 1, the electronic switch on elements 23-25 carries out the OSO (PGC) and OSI (PGD) microcontroller outputs the NEX file in the FLASH program memory and the microcontroller EEPROM data memory with the subsequent verification of the microcontroller programming error . Since the list of PIC microcontrollers programmed by the utility model is very large, when programming various types of microcontrollers, cases are sometimes possible when voltage regulation at the MCLR pin of the microcontroller is necessary using trimmer resistor 11.

In the considered standard (working) programming mode (see Fig.), The device of adjustable protection against failure of programmable PIC microcontrollers introduced into the model, consisting of elements 26-29, does not change the programmer’s principle of operation, but “expects” non-standard situations, in which it will protect the programmable PIC microcontroller.

2. Non-standard programming modes (see. Fig.). In both non-standard situations, the current through the MCLR pin (12.0-13.5 V) of the microcontroller rises and reaches a value of about 200 mA acceptable for the PIC microcontroller. In this case, the voltage drop between the cathode of the low-power thyristor 26 and the engine of the measuring tuning resistor 28 reaches a value of about 100 mV, which opens the low-power thyristor 26 through the resistor of the control circuit 27. An open low-power thyristor 26 shunts the base of the transistor 10 and the voltage at the output of the MCLR of the DIP panels 17 , 18 and 19 tends to 0 V (does not exceed 100 mV), which keeps the programmable PIC microcontroller intact. Next, you need to eliminate the non-standard situation and press the reset button 29. The voltage at the MCLR pin is restored to 12.0-13.5 V. The microcontroller must be correctly installed in the DIP-panel of the programmer and programmed. The list of PIC microcontrollers programmed by the utility model is quite large, therefore, when programming various types of microcontrollers (middle or older generation), cases are sometimes possible when it is necessary to adjust the voltage drop across the measuring trimmer resistor 28 using its engine.

Thus, the exclusion from the prototype of the protection device, consisting of a ballast resistor, a reference diode, and a regulating transistor, and a programmable PIC microcontroller introduced in a utility model from a failure in non-standard situations, consisting of: low-power thyristor 26 (2U101B); limit resistor 27 (3.3 kOhm); a measuring tuning resistor 28 (1 Ohm) and a normally open reset button 29, does not change the principle of the programmer in standard situations, but maintains the operability of modern eight-bit PIC microcontrollers by limiting the programming current through the microcontroller to the maximum allowable level when the above non-standard situations occur:

- Installation of PIC-microcontrollers in the DIP-panel of the programmer with a turn of 180 (from the normal location;

- unreliable contact or its absence at all between the same contacts V _ss and V _{dd of the} PIC microcontroller and the DIP panel of the programmer.

Claims (1)

PIC microcontroller programmer with adjustable overload protection, containing three panels for installing DIP-18, DIP-28 and DIP-40 microcontrollers, in which ceramic blocking capacitors are installed between the V _ss and V _dd terminals, a COM port for connecting to a computer, a rectifier with sequential doubling and voltage stabilization with two electrolytic and two blocking ceramic capacitors, which is fed by the clock pulses of the COM port, a transistor in key mode with protective diodes in the MCLR output circuit for the bottom the programming voltage to the microcontroller, the switch on the transistor, which supplies programming signals from the COM port to the OSI (PGD) terminal of the microcontroller and verifies the programming results from the OSO (PGC) terminal, a transistor voltage regulator to set the operating programming voltage to the MCLR terminal of the microcontroller, characterized in that the model includes a device for adjustable protection against failure of programmable PIC microcontrollers in non-standard situations, consisting of low-power a thyristor-limiting resistor, measuring trimmer and normally open reset button.