SN8P275X Series
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 67
Version 0.7
6.4 GIE GLOBAL INTERRUPT OPERATION
GIE is the global interrupt control bit. All interrupts start work after the GIE = 1 It is necessary for interrupt service
request. One of the interrupt requests occurs, and the program counter (PC) points to the interrupt vector (ORG 8) and
the stack add 1 level.
0DFH
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
STKP
GIE
- - - -
STKPB2
STKPB1
STKPB0
Read/Write
R/W
- - - -
R/W
R/W
R/W
After
reset
0 - - - - 1 1 1
Bit 7
GIE:
Global interrupt control bit.
0 = Disable global interrupt.
1 = Enable global interrupt.
Example: Set global interrupt control bit (GIE).
B0BSET
FGIE
; Enable GIE
Note: The GIE bit must enable during all interrupt operation.
6.5 PUSH,
POP
ROUTINE
When any interrupt occurs, system will jump to ORG 8 and execute interrupt service routine. It is necessary to save
ACC, PFLAG data. The chip includes “PUSH”, “POP” for in/out interrupt service routine. The two instructions save and
load
ACC
,
PFLAG
data into buffers and avoid main routine error after interrupt service routine finishing.
Note: ”PUSH”, “POP” instructions save and load ACC/PFLAG without (NT0, NPD). PUSH/POP buffer is an
unique buffer and only one level.
Example: Store ACC and PAFLG data by PUSH, POP instructions when interrupt service routine executed.
ORG
0
JMP
START
ORG
8
JMP
INT_SERVICE
ORG
10H
START:
…
INT_SERVICE:
PUSH
; Save ACC and PFLAG to buffers.
…
…
POP
; Load ACC and PFLAG from buffers.