Intel 8XC196NT, User Manual

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8XC196NT USER’S MANUAL
C-30
EPAIPV
EPAIPV
Address:
Reset State:
1FA8H
00H
When an EPA x interrupt occurs, the EPA interrupt priority vector (EPAIPV) register contains a number
that identifies the highest priority, active, multiplexed interrupt source (see Table 10-6).
EPAIPV allows software to branch via the TIJMP instruction to the correct interrupt service routine
when EPA
x is activated. Reading EPAIPV clears the EPA pending bit for the interrupt associated with
the value in EPAIPV. When all the EPA pending bits are cleared, the EPA x pending bit is also cleared.
7 0
— — — PV4 PV3 PV2 PV1 PV0
Bit
Number
Bit
Mnemonic
Function
5:7 — Reserved; always write as zeros.
4:0 PV4:0 Priority Vector
These bits contain a number from 01H to 14H corresponding to the
highest-priority active interrupt source. This value, when used with the
TIJMP instruction, allows software to branch to the correct interrupt
service routine.
Table C-7. EPA Interrupt Priority Vectors
Value Interrupt Value Interrupt Value Interrupt
14H EPA4 0DH OVR1 06H OVR8
13H EPA5 0CH OVR2 05H OVR9
12H EPA6 0BH OVR3 04H COMP0
11H EPA7 0AH OVR4 03H COMP1
10H EPA8 09H OVR5 02H OVRTM1
0FH EPA9 08H OVR6 01H OVRTM2
0EH OVR0 07H OVR7 00H None