The Sinclair QL Forum

put both files in the same folder and run the miniconfig from that one , should work

I have both files: miniconfig_bas and I2C_IO_BIN on flp1_ main dir...
I do following things:
turn on QL
tk2_ext
lrespr flp1_I2C_IO_BIN
lrun flp1_miniconfig_bas
Am I missing sth?

tommy.sz wrote: Tue Aug 05, 2025 10:06 am I have both files: miniconfig_bas and I2C_IO_BIN on flp1_ main dir...
I do following things:
turn on QL
tk2_ext
lrespr flp1_I2C_IO_BIN
lrun flp1_miniconfig_bas
Am I missing sth?

Odds are you have a bad pfc8583 chip.

I have made a tester just to sort this out! Both the arduino sketch and a gerbers are attached.

Enjoy!

Thank you for your efforts!!
I will try another chip.
I will also build your tester although I've already tested the clock on a breadboard to see if the circuit is correct and it worked.
What I haven't tested and I'm not sure how to test is whether the I2C communication circuit based on GAL logic works...
I will try logic analyzer to see SDA and SCL signals but not sure if I'm able to interpret them correctly.
I will also try other copies of the Minerva MKII files in case they got corrupted in the process of transferring to disk.
For sure I let you and the rest of humanity know when it is (hopefully) solved.
Thank you again!

I will try logic analyzer to see SDA and SCL signals but not sure if I'm able to interpret them correctly.

Most logic analysers will decode i2c for you!