Hello everyone, thank you for browsing.I plan to rebuild this QA45 host,I drew the schematic and read by programmer the firmware.
But there was an error in the circuit diagram at the back of the manual,For example, when IC16 is labeled as LH5160HD on the circuit diagram, it has 32 pins, but the actual circuit board has LH5164 with only 28 pins,So the signal lines uPA13 and uPA14 will be lost.
The main chip of the motherboard is MC68HC11G5FN, the RAM chip is LH5164A, the ROM chip is 27C1001, and the PLD chip is 22V10Z.
The initial version of the schematic diagram is located on page 57 of the "Metron_QA-45_ - Manual. pdf" file.
The file "1Processor Board1_2023-09-05.zip" is a schematic diagram that I have redrawn and is the same as the actual image. The firmware is extracted from here
I don't have a real PCB circuit board. The circuit board in the picture was taken and provided to me by my friend.So I can't measure the authenticity of the verification signal
I have obtained the internal firmware of 27C1001 on the real motherboard. If you could reverse compile it and tell me the actual connection and wiring, I would greatly appreciate it. Thank you for your help