Chip Erase with 93C66 EEPROM not working with IMSProg and CH341A v1.2/1.7 #167
Description
Distribution
Ubuntu 24.04 noble
Architecture
x86_64
Kernel version
6.8.0-90-generic Linux Mint 22.3 Zena
IMSProg version
V1.7.2
Bug description
IMSProg chip erase function not working with 93C66 IC de-soldered from PCB and placed in SOP8 adapter and into CH341APro black edition ZIF connector.
Steps to reproduce
After Ctrl+E depressed, the RUN LED on the CH341A programmer illuminates for about 1 sec and progress bar on IMSProg GUI shows 50% concurrently with the RUN LED ON then back to 0% after RUN LED turns off. Performing chip read Ctrl+R after chip ERASE does NOT read all FF in all memory addresses, rather it reads the same CRC32 as the original buffer state before CHIP ERASE activated. I am able to read, write and verify successfully no problem. The workaround for this issue I found is to re-select chip Type, Manufacture, and Name, which loads FF everywhere in the buffer initially and then perform a Ctrl+W chip WRITE and Ctrl+T VERIFY step to confirm the ERASE ALL was successful.
Expected behavior
Expect to read FF in all memory locations after CHIP ERASE Ctrl+E.
Additional information
93C66 datasheet clearly indicates VCC=4.5-5.5 V compared to the 3.3V in the IMSProg database. These chips often used in automotive with 5.0V supply rails
This chip seems robust as read/write/verify behavior successful with either 3.3V or 5V VCC set on CH341A programmer.