Iprog Rework !free! -

iprog rework — Comprehensive Commentary

3. TVS Diode and ESD Protection

The original clone has zero protection against electrostatic discharge (ESD) or overvoltage on the programming pins. One accidental short during bench programming can kill the main PIC18F microcontroller.

Rework Steps:

  • Solder a 5.6V Zener diode (e.g., 1N4734A) between Vpp and ground on every adapter board header.
  • Install a TVS diode array (e.g., USBLC6-2SC6) on the USB D+/D- lines to protect the CH340G USB-to-serial chip.
  • Add series resistors (100 Ohm) on all data lines (MOSI, MISO, SCK) to limit current during a short circuit.

Result: Your IProg can survive accidental miswiring and static discharge from bench handling. iprog rework

Phase 1: The Hardware Surgery

"Rework" is a polite word for surgery. We cracked open the enclosure to find exactly what we expected: a decent PCB layout hidden under years of production dust and a few questionable solder joints. iprog rework — Comprehensive Commentary 3

The Essential Components of an IProg Rework

A complete rework involves five distinct stages. Below, we break down each step with technical precision. Solder a 5

Adding External Vpp Control

Install a potentiometer and voltage reference to manually adjust Vpp from 0V to 25V. This allows programming older EPROMs (27C series) that require 21V or 25V.

C. Error Handling & Logging

  • Granular Feedback: The system now distinguishes between hardware connection faults, target power faults, and data verification mismatches.
  • Verbose Logging: A debug mode was added to output a timestamped log of every register write/read, facilitating easier failure analysis (FA) by the engineering team.

9. Post-Rework Verification

  1. Connect IProg to PC → should appear as HID or serial device.
  2. Launch IProg software → check firmware version matches.
  3. Test read/write on a known working vehicle transponder or immobilizer dump.
  4. Self-test (if available in software): check voltage, crystal, EEPROM.

A. Bricked after bad update

  • Force bootloader via BOOT0 → erase → flash original firmware.