Topic : The ATARI Compendium
Author : Scott Sanders / JAY Software
Version : 1.25 (20/6/2003)
Subject : Documentation
Nodes : 1117
Index Size : 32614
HCP-Version : 6
Compiled on : Atari
@charset : UTF-8
@lang : en
@default :
@help : %About
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View Ref-FileKeyboard ACIA (6850)Location(s) SizeBYTE Occupies one byte (8 bits).
WORD Occupies one WORD (16 bits).
LONG Occupies one longword (32 bits).
OW Occupies the odd WORD of a LONG.
EW Occupies the even WORD of a LONG.
OB Occupies the odd BYTE of a WORD.
EB Occupies the even BYTE of the WORD.
MchnIf the box is shaded then address is available
for this computer.
▒ ▒ ▒ ▒ ▒ ▒
| | | | | '------- Falcon030
| | | | '--------- TT030
| | | '----------- MEGA STe
| | '------------- STe
| '--------------- MEGA ST
'----------------- STTypeROM Location is Read-Only Memory
RAM Location is Read-Write Memory
I/O Location is hardware-mapped
VME Location addresses VME address space
N/A Not applicable
RO Read-only location
WO Write-only location
RW Read-write location
RSVD Reserved
Unassigned Either not assigned or undocumented
Meaning (see Usage)
▒▒▒▒▒▒
0x00FFFC00 EB ▒▒▒▒▒▒ I/O Keyboard ACIA Control (when written) as
▒▒▒▒▒▒ follows:
▒▒▒▒▒▒
▒▒▒▒▒▒ Bit #7
▒▒▒▒▒▒ Enables receive interrupts
▒▒▒▒▒▒
▒▒▒▒▒▒ Bits #6-5
▒▒▒▒▒▒ Configures transmitter interrupts
▒▒▒▒▒▒ as follows:
▒▒▒▒▒▒
▒▒▒▒▒▒ Value Meaning
▒▒▒▒▒▒ 00 RTS low, Disable Interrupts
▒▒▒▒▒▒ 01 RTS low, Enable Interrupts
▒▒▒▒▒▒ 10 RTS high, Disable Interrupts
▒▒▒▒▒▒ 11 RTS low, Disable Interrupts
▒▒▒▒▒▒ Send a break on Interrupt
▒▒▒▒▒▒
▒▒▒▒▒▒ Bits #4-2
▒▒▒▒▒▒ Configure Port Settings as follows:
▒▒▒▒▒▒
▒▒▒▒▒▒ Value Data Bits_Parity_Stop Bits
▒▒▒▒▒▒ 000 7-E-2
▒▒▒▒▒▒ 001 7-O-2
▒▒▒▒▒▒ 010 7-E-1
▒▒▒▒▒▒ 011 7-O-1
▒▒▒▒▒▒ 100 8-N-2
▒▒▒▒▒▒ 101 8-N-1
▒▒▒▒▒▒ 110 8-E-1
▒▒▒▒▒▒ 111 8-O-1
▒▒▒▒▒▒
▒▒▒▒▒▒ Bits #1-0
▒▒▒▒▒▒ Set Clock Divisor as follows:
▒▒▒▒▒▒
▒▒▒▒▒▒ Value Meaning
▒▒▒▒▒▒ 00 Normal
▒▒▒▒▒▒ 01 Divide by 16
▒▒▒▒▒▒ 10 Divide by 256
▒▒▒▒▒▒ 11 Master Reset
▒▒▒▒▒▒
▒▒▒▒▒▒ Keyboard ACIA Control (when read) as
▒▒▒▒▒▒ follows:
▒▒▒▒▒▒