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36 lines
1.2 KiB
Plaintext
36 lines
1.2 KiB
Plaintext
PIOMON is a program to verify operation of the Z80 MBC DUALPIO board
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Most testing requires the use of loopback hardware constructed as:
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Channel A RDY STB D0 D1 D2 D3 D4 D5 D6 D7
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\ / | | | | | | | |
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\ / | | | | | | | |
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X | | | | | | | |
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/ \ | | | | | | | |
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/ \ | | | | | | | |
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Channel B RDY STB D0 D1 D2 D3 D4 D5 D6 D7
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The DUALPIO has, well, 2 PIO chips. Only one chip
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is tested at a time. At startup, PIOMON will ask
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you for the port of the chip to test. It defaults
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to the standard port number for the primary PIO chip
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on an MBC DUALPIO board.
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The port number specified is the base I/O port. Each
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chip has two channels which are addressed in the
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menu by specifying A or B.
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MBC DUALPIO Primary PIO = 0xB8
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MBC DUALPIO Secondary PIO = 0xBC
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If you try to use PIOMON without the RDY and STB
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cross connected, you may have interrupt issues
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because STB will be floating.
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N.B., V1 and V2 of the DUALPIO lack a hardware reset. The
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PIO chips will reset at power-on, but they do not reset
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when the reset button is pushed.
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Happy St. Patrick's Day!!!
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--WBW 7:42 PM 3/17/2022 |