PIC programmer: High voltage
High-voltage parallel port programmer
This programmer works on Flash based PIC microcontrollers. It is based on a design by David Tait but uses schmitt triggers as buffers for improved stability.
- 16F628
- 16F870 - tested
- 16F873
- 16F874
- 16F876
- 16F877
Schematics:
12V - Not critical, must be at least 3.5V above Vdd. 5V - Must be regulated. Q1 - Most small signal transistors will work. C1 - Not critical, decouples both the PIC and the 74HCT14. R1-R3 - Not critical. 74HCT14 - Must be a HCT part.
The parallel cable should be as short as possible, it did work on a 1.5 metre extension cable but should be tested with a short cable
Pinouts:
12V - Not critical, must be at least 3.5V above Vdd. 5V - Must be regulated. Q1 - Most small signal transistors will work. C1 - Not critical, decouples both the PIC and the 74HCT14. R1-R3 - Not critical. 74HCT14 - Must be a HCT part.
The parallel cable should be as short as possible, it did work on a 1.5 metre extension cable but should be tested with a short cable
Pinouts: 74HCT14
PIC16F870
Programming Software:
David Tait's Flash PIC Programme (FPP) (Mirror: fpp09.zip 183 KB)
Click "Setup" and change the settings to:
Click "Define/Test" and change the settings to:
remember to click "Apply"!!!
Load the test program "16F870.HEX" Set "Config" to 3F71 Click "Program"
A LED between GND and RB0-RB7 will show flashing at different frequencies:
The source code is here "16F870.asm"
Reference:
