Willem Programmer: Basic Troubleshooting Notes     2020/03/15
by Ami Sapphire


Last Updated: 2020/04/15

2020

[0404]
Inconsistent reads/writes/erasures changed to Failed or inconsistent
  reads/writes/erasures due to more information
Added weak EPROM pins to reads/writes/erasures section

[0415]
Added important note regarding 0.98d12c4 and PCB5 variant programmers
Made 0.97ja the universal release to all Willem programmers as it is one of the
  most stable releases


Programmer not recognized

- Bad power adapter
  * Check for power. (Easiest with voltmeter.)
    + Voltage - Willem PCB3[b]-based programmers: 9-12V avg.
    + Voltage - Willem 3.0/Willem 4.0-based programmers: 16-25V avg., depending
      on what type of EPROMs are used


Failed or inconsistent reads/writes/erasures

- Bad parallel data cable or dirty contacts on parallel data cable
  * Clean contacts on both male and female ends of cable with contact spray.
  * If that fails, replace parallel data cable.

- Bad parallel connector or dirty contacts on parallel connector of programmer
  * Check for bent pins on programmer's parallel connector.
  * Clean contacts on programmer with contact spray.
  * Touch-solder parallel connector with soldering iron.
  * If all else fails, have the parallel connector replaced.
    + Connector type: Right Angle DB25 Male Connector

- Buggy software
  * Most stable programming software versions to use [0.97ja is universal]:
    + Willem 4.0/4.1-based and earlier: 0.97g
    + PCB3[b]-based and earlier: 0.97d12c3
    + PCB3.5-based: 0.98b
    + PCB4.5-based: 0.98d5
    + PCB5 and later: 0.98d12c3, 0.98d12c4
      ! IMPORTANT ! - If you are going to use large 16-bit 27C EPROMs (e.g.,
      400/800/160/322) with this PCB revision programmer, do NOT use 0.98d12c4!
      There are intermittent timing issues when attempting to write to these
      EPROMs and you must use 0.98d12c3 instead! This is with the ADP-054
      adapter; not sure with other 16-bit EPROM adapters.

- Weak EPROM pins on EPROM chip
  * If all pins are present:
    + Carefully straighten out pins.
    + Meticulously touch solder all pins on the chip. This is assuming the pins
      are not tinned (soldered).
  * If one or few pins are partially broken:
    + Repair partially broken pins before attempting to use the chip again.
  * If one or few pins are completely gone:
    + It is still somehow possible to salvage it in some cases.
	+ If it is not possible to repair the chip, then consider it a lost cause.