ST7LITE0xY0, ST7LITESxY0
INTERRUPTS (Cont’d)
EXTERNAL INTERRUPT CONTROL REGISTER
(EICR)
Read / Write
Reset Value: 0000 0000 (00h)
7
0
IS31 IS30 IS21 IS20 IS11 IS10 IS01 IS00
Bit 7:6 = IS3[1:0] ei3 sensitivity
These bits define the interrupt sensitivity for ei3
(Port B0) according to Table 7.
Bit 5:4 = IS2[1:0] ei2 sensitivity
These bits define the interrupt sensitivity for ei2
(Port B3) according to Table 7.
Notes:
1. These 8 bits can be written only when the I bit in
the CC register is set.
2. Changing the sensitivity of a particular external
interrupt clears this pending interrupt. This can be
used to clear unwanted pending interrupts. Refer
to section “External interrupt function” on page 42.
Table 7. Interrupt Sensitivity Bits
ISx1 ISx0
00
01
10
11
External Interrupt Sensitivity
Falling edge & low level
Rising edge only
Falling edge only
Rising and falling edge
Bit 3:2 = IS1[1:0] ei1 sensitivity
These bits define the interrupt sensitivity for ei1
(Port A7) according to Table 7.
Bit 1:0 = IS0[1:0] ei0 sensitivity
These bits define the interrupt sensitivity for ei0
(Port A0) according to Table 7.
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