NEC Advanced Personal Computer System Reference Manual page 42

Processor PCB
Table 2-5 Interrupt Control Commands Summary (cont'd)
READ/ I/O
DATA BUS
DEVICE INSTRUCTION WRITE ADDRESS 7 6 5 4 3 2 1 0
OCW 1 W 2A
MI4 M13 M12 MIl MIO M9 M8 M7
OCW2
W 28 R S E 0 0
L2 L1 LO
L 0
I
OCW3
W 28 0 E S 0
1 P R R
S M
R I
M M
S
Poll Mode R 28 I -
- - - W2 WI WO
Read IRR
IR IR IR IR IR
IR IR IR
R 28
14
13 12 11 lO 9 8 7
Read IRR
IS IS
IS IS IS IS IS IS
R 28
14 13 12
11
lO
9 8 7
Read Mask R 2A
M 14 M 13 M 12 MIl M 1 0 M9 M8 M7
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