Getting closer to HAC-1

The main parts (CPU and memory chips) have been ordered, and we did some work on the PCB design today... lots of interesting (maybe?) updates to come, and hopefully in a few weeks we might have this thing up and running!

So far:

No JTAG connector since we don't have any JTAG hardware to begin with (maybe add one if really necessary).
Programming the CPU's internal flash may be done with the in-system programming option via UART. When "in-system programming enable" pin is asserted at reset, the hard-coded bootloader takes over the CPU for ISP.
Since max232 chips and related circuitry are a big waste of board space, we're going with 6-pin headers for FTDI chip TTL232R 3V3 cables for this.

VLSI MP3 chip for audio.
PS/2 port for keyboard input.
12-bit color video output from LCD controller.
SD Card connector added.

There's lots of room left on the board, so we may consider an ethernet interface, and we will definitely add some general purpose IO.

This gentleman down in Nagoya has very recently built something similar to what we are doing, and was kind enough to share schematics and PCB layout.

I was hoping for some insight on how to wire up the memory with the very inconvenient pin assignments, but Havard seems to have done OK with that anyway.

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