Willem programmer software version 0.97ja

Programmer jumpers - W/Jp1- wire cable to dc2dc_a4, Jp3 (+5V), Jp4 (Vpp)
plcc32f1 jumpers A…E according to density –
A,C,E,G (64kb,128kb); A,C,F,H (256kb), B,D,F,H (512kb), jumper I (A9)

27C64, 27C128, 27C256, 27C512
Selected device EPROM > 27Cxxx > …, twp=140mks
dc2dc_a4 jumpers – JpR (Vcc from LM317), JpM (Vcc=5.8V) , JpP (Vpp=11..14V)
Adjust R5 - Vpp=12.8V
Verified chips :
AM27C256, AT27C256R, MX27C256QC, Microchip 27C256, ST Micro M27C256B,
AT27C512R, Microchip 27C512, MX27C512QC, Signetic 27C512, ST Micro M27C512, TMS27PC512

Electrically erasable EPROM
Selected device EPROM Electrical Erase >…

W27E/C256, W27E/C512, MX26C512, SST27SF256/512
dc2dc_a4 jumpers – JpR (Vcc from LM317), JpP (Vpp=11…14V)
Erase – adjust R5- Vpp=14.0V (W27…), Vpp=12.8V (MX26C…), Vpp=12.0V (SST27SF…)
Set jumper JpJ. Action Erase. Set back jumper JpI !!

Program – adjust R5- Vpp=12.0V (W27…, SST27SF…), Vpp=12.8V (MX26C…, set jumpers M, N, Vcc=6.2V)
SST27SF256 can be programmed without dc2dca4, set jumpers JpK, JpL (+5, +12V from programmer).
Verified chips: W27C512P, W27E512P, SST27SF256, SST27SF512
MX26C512AQC – fail, not supported on 0.97ja.

Chip test results find in chip_test.xls file.
Note.
Chips are tested in long period, different dc2dc adapters and voltages used, SW 0.97g and 0.97ja .
dc2dca4 is functionally equal to previous versions (a2, a3; same jumpers). Adjust other Vpp value or change Vcc=6.2V (jumper N), change twp, if required from EPROM datasheets or programming fail.
64k, 128k, 256k chip read available without dc2dc_a4, some can be programmed. Set jumpers JpK, JpL. (Vcc=5V, Vpp=12V).

How to adjust Vpp ?
Install dc2dc_a4 and eprom adapter without target chip on ezoflash+.
Connect power supply, PC and run SW. Adjust Vpp on LM317- IN with R5
Chips in PLCC-32 package (except electrically erasable) are OTP (one time programmable) and cannot be erased. Only new EPROM can be programmed, all bits of the EPROM are in the logic high state.
Run SW command Blank check to assure all bytes are 0xFF.
Logic lows are programmed into desired locations. Repeat programming (check voltage, increase twp) on logic low programming failure.

Report problems and share your experience on Willem and EZoFlash forums.