Why the Z-80’s data pins are scrambled
Quote:
I have been reverse-engineering the Z-80 processor using images and data from the Visual 6502 team. The image below is a photograph of the Z-80 die. Around the outside of the chip are the pads that connect to the external pins. (The die photo is rotated 180° compared to the datasheet pinout, if you try to match up the pins.) At the right are the 8 data pins for the Z-80's 8-bit data bus in a strange order.
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