Apple Lisa - Page 29

Confidential
Lisa Hardware Reference Manual
6522
REGISTER ADDRESSES
Register
Reg!;
Register Function Address
ORB/IRB
0 Output/Input Register
B $00D181
ORA/IRA 1 Output/Input. Register A $00D183
DDRB 2 Data Direction Register B $00D185
DDRA 3 Data Direction Register A $00D187
TIC-L
4
Tl Low-order
Latches/Counter $00D189
TlC-H 5 Tl High-order Counter $00D18B
TIL-L 6 Tl Low-order Latches $00D18D
TIL-H
7 Tl High-order Latches $00D18F
T2C-L 8 T2 Low-order Latches/Counter $00D191
T2C-H 9 T2 High-order Counter
$00D193
SR 10 Shift Register $00D195
ACR
11 Auxiliary Control Register $00D197
PCR
12
Peripheral Control Regist~r $00D199
IFR 13 Interrupt Flag Register $00D19B
IER
14
Interrupt Enable Register $00D19D
ORA/IRA 15
Same as Register 1 but without
handshaking $00D19F
Register 15 should be used when transferring commands to the COPS.
All the 6522 register addresses are in the I/O address space. The
T1 timer in the 6522 is reserved for use as an interval timer by the
Operating System. For further details about the 6522, read the 6522
data sheet in the Synertek MaS Data Catalog.
Page 29
7-Jul-81