Build your own flexible & easy to built Atmel 89C series flash programmer

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Introduction

This programmer was designed in view of to be flexible, economical and easy to built, the programmer hardware utilizes the standard TTL series parts and no special components are used. The programmer is interfaced with the PC parallel port and there is no special requirement for the PC parallel port, so the older computers can also be used with this programmer.

Devices

At present the programmer software supports the following Atmel devices

AT89C51

AT89C52

AT89C55

AT89C1051

AT89C1051U

AT89C2051

AT89C4051

Note:  For 20 pin devices a simple interface adapter is required.

Hardware

Figure 1 shows the circuit diagram of the Flash Programmer, the programmer is interfaced with the standard parallel port of the PC. As shown in the diagram U1 is used to control the data flow between controller and the pc, U3 latched the low order address byte and U4 latched the high order address byte, while U2 is used to generate the control signals for micro-controller to be programmed. The power supply section uses U6 to generate the logic 5V supply while the U5 is used to provide the programming supply voltage to controller. The power to the circuit is provided by a wall adapter of 15 to 18V output, normally a 15V type adapter will provide a 19~20V output voltage. As shown in the diagram the crystal X1 can be replaced by a resonator in that case capacitors C4 and C5 are not required, the pcb has the provision for both type of devices.
Adjustment procedure for P1 and P2 variables.
1. First adjust P1 to get the 12.75V at the output of LM317 regulator. Make sure transistor T4 is off or 
    temporarily connect the T4 base to ground.
2. Now temporarily short the collector of transistor T4 to ground.
3. Adjust P2 to get the 12.0V at the output of LM317 regulator.

Figure 2 shows the circuit diagram of the interface adapter card required for the programming of 20 pin Flash devices.

Constructing the Board

The prototype board may be built using universal PCB with point-to-point wiring. If you want to make a PCB, get the PCBs.zip file which contains the printer files *.PRN for HP Laser printer and the plotter files *.PLT for the HP Pen plotter. Figure 3 shows the component layout of the programmer pcb.
For printing the files on laser printer issue the following dos command

COPY FILENAME.PRN PRN/B

For the bill of material of the project get the file Pgm89bom.txt
The schematics and the pcbs of the project were designed using OrCAD software.

Software

Pgm89.exe file is used to run the programmer. This is a DOS program which can also be used in Windows 95 and 98 msdos window but not in windows NT. The main screen of the program is shown in figure 4.

Following are the main features of this software,

Read and Write Intel Hex File

Read Chip info

Verify from hex file

Program Lock Bits

Fill buffer & Display buffer

Parallel Port selection LPT1, 2 & 3

Remember the previous settings of the programmer

 

Note: In order to insure safe insertion & removal of the u-controller from programmer zif socket make sure programmer power supply is turned on before starting the program and the red LED D2 must be turned off.

Figure 4: Main screen of the program PGM89.exe

Future Enhancement

The programmer hardware is also capable to program the following Atmel devices, the next version of the software also include these devices.

AT89S53           12K flash with SPI and wd-timer

AT89S8252       8K flash, 2K e2rom with SPI and wd-timer

AT89C51RC     32K flash, 512 byte ram, dual dptr and wd-timer

AT89C55WD    20K flash with dual dptr and wd-timer

A separate program PGME2.exe is also under development which can be used to program the following
parallel EEPROM devices using a simple interface adapter with the above mentioned programmer.

28C17

28C64

28C256

29C256