Topic       : Pure Assembler Documentation
Author      : John Kormylo
Version     : PASM.HYP 1.0
Subject     : Documentation/Pure Assembler
Nodes       : 740
Index Size  : 20262
HCP-Version : 3
Compiled on : Atari
@charset    : atarist
@lang       : en
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@help       : Help
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View Ref-File[ MC6850 Asynchronous Communications Interface Adapter ]

The ACIAs are used for the MIDI port and to communicate with the
keyboard (IKBD).  The CTS, DCD, and RTS are not connected.

Settings are for 8 bit word length, 1 stop bit and no parity.
The Baud rate for the IKBD is 7812.5 (500 KHz/64).
The Baud rate for the MIDI is 31250 (500 KHz/16).
Both use MFP GPIP bit 4 for interrupt request (see ST MFP).

ACIA Control Register (on write)
ACIA Status Register (on read)

XBIOS: Midiws, Ikbdws and Kbdvbase.