
ST7267C8 ST7267R8
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ST7 INTERRUPTS (Cont’d)
EXTERNAL INTERRUPT CONTROL REGISTER
0 (EICR0)
Read/Write
Reset Value: 0000 0000 (00h)
Bit 7:6 =ISD[1:0] Port D ei3 sensitivity IT[31-24]
The interrupt sensitivity, defined using the ISD[1:0]
bits, is applied to the ei3 external interrupts:
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
Bits 5:4 = ISC[1:0] Port C ei2 sensitivity IT[23-16]
The interrupt sensitivity, defined using the ISC[1:0]
bits, is applied to the ei2 external interrupts:
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
Bits 3:2 = ISB[1:0] Port B ei1 sensitivityIT[15-8]
The interrupt sensitivity, defined using the ISB[1:0]
bits, is applied to the ei1 external interrupts:
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
Bits 1:0 = ISA[1:0] Port A ei0 sensitivity IT[7-0]
The interrupt sensitivity, defined using the ISA[1:0]
bits, is applied to the ei0 external interrupts:
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
EXTERNAL INTERRUPT CONTROL REGISTER
1 (EICR1)
Read/Write
Reset Value: 0000 0000 (00h)
Bit 7:2 = Reserved, must be kept cleared.
Bit 1:0 =ISE[1:0] Port E ei4 sensitivity IT[39-32]
The interrupt sensitivity, defined using the ISE[1:0]
bits, is applied to the ei4 external interrupts:
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
PORT A EXTERNAL INTERRUPT ENABLE
REGISTER (PAEIENR)
Read/Write
Reset Value: 0000 0000 (00h)
70
ISD1
ISD0
ISC1
ISC0
ISB1
ISB0
ISA1
ISA0
ISD1 ISD0
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
ISC1 ISC0
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
ISB1 ISB0
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
ISA1 ISA0
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
70
000000
ISE1
ISE0
ISE1 ISE0
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
70
IT7E
IT6E
IT5E
IT4E
IT3E
IT2E
IT1E
IT0E