42 行
1.5 KiB
Markdown
42 行
1.5 KiB
Markdown
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# Z80-MBC2
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The [Z80-MBC2][link] combines a Z80 and an ATMEGA32A to provide a CP/m capable
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computing environment. It features a SD card bootloader which makes running
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Collapse OS on it rather simple.
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## Recipe
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In this recipe, we're going to run Collapse OS on the Z80-MBC2, interfacing
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through its serial port. We're going to use the MBC's API to implement BLK on
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the SD card. (the BLK part isn't done yet. TODO)
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### Gathering parts
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* A Z80-MBC2 computer with its SD card module and a properly flashed "IOS" on
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the ATMega32A.
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* A FTDI-to-TTL cable to connect to the serial port.
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### Building the binary
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Running `make` will yield `os.bin` which is what we want.
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### Running on the Z80-MBC2
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Mount the SD card on your modern computer and copy `os.bin` as `autoboot.bin`,
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overwriting the binary that was previously there.
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Put back the SD card in the Z80-MBC2 and power it up by connecting the FTDI
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adapter to it (red: VCC, black: GND, green: TX, white: RX).
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The FTDI adapter will show up as something like `ttyUSB0` (or `ttyU0` on
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OpenBSD). Connect to it with `screen` or `cu` or whatever you like. Baud rate of
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the Z80-MBC2 appears to be hardcoded to 115200.
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Then, enable IOS program selection by holding RESET and USER at the same time,
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wait 2 seconds, releasing RESET, wait 2 seconds, releasing USER. You should then
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be given a 1-8 choice, with 4 being "Autoboot". Type 4.
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You are now in Collapse OS.
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[link]: https://hackaday.io/project/159973-z80-mbc2-a-4-ics-homebrew-z80-computer
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