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COUNTER CONFIGURATION
BADR3 + 13 hex
READ/WRITE
7
6
D7
D6
This register is used to set the operating modes of each of the 82C54's counters.
Configure the counters by writing mode information to the Configure register,
followed by the count information written to the specific counter (data) registers.
Refer to the Celeritous 82C54 data sheets for more detailed information.
5.4.6 8255 Interrupt Source Configure
BADR3 + 14 hex
READ/WRITE
7
6
DIRQ1
DIRQ0
DIRQ1
When this bit is set, the 8255 in Group 3 will generate an interrupt on
INTRB if INTEN in BASE +15 hex is also set.
DIRQ0
When this bit is set, the 8255 in Group 3 will generate an interrupt on
INTRA if INTEN in BASE +15 hex is also set.
CIRQ1
When this bit is set, the 8255 in Group 2 will generate an interrupt on
INTRB if INTEN in BASE +15 hex is also set.
CIRQ0
When this bit is set, the 8255 in Group 2 will generate an interrupt on
INTRA if INTEN in BASE +15 hex is also set.
BIRQ1
When this bit is set, the 8255 in Group 1 will generate an interrupt on
INTRB if INTEN in BASE +15 hex is also set.
BIRQ0
When this bit is set, the 8255 in Group 1 will generate an interrupt on
INTRA if INTEN in BASE +15 hex is also set.
AIRQ1
When this bit is set, the 8255 in Group 0 will generate an interrupt on
INTRB if INTEN in BASE +15 hex is also set.
AIRQ0
When this bit is set, the 8255 in Group 0 will generate an interrupt on
INTRA if INTEN in BASE +15 hex is also set.
5
4
D5
D4
5
4
CIRQ1
CIRQ0
16
3
2
D3
D2
3
2
BIRQ1
BIRQ0
1
0
D1
D0
1
0
AIRQ1
AIRQ0
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