ST72325xx
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7.7 EXTERNAL INTERRUPT CONTROL REGISTER (EICR)
Read/Write
Reset Value: 0000 0000 (00h)
Bit 7:6 = IS1[1:0] ei2 and ei3 sensitivity
The interrupt sensitivity, defined using the IS1[1:0]
bits, is applied to the following external interrupts:
- ei2 (port B3..0)
- ei3 (port B4)
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
Bit 5 = IPB Interrupt polarity for port B
This bit is used to invert the sensitivity of the port B
[3:0] external interrupts. It can be set and cleared
by software only when I1 and I0 of the CC register
are both set to 1 (level 3).
0: No sensitivity inversion
1: Sensitivity inversion
Bit 4:3 = IS2[1:0] ei0 and ei1 sensitivity
The interrupt sensitivity, defined using the IS2[1:0]
bits, is applied to the following external interrupts:
- ei0 (port A3)
- ei1 (port F2..0)
These 2 bits can be written only when I1 and I0 of
the CC register are both set to 1 (level 3).
Bit 2 = IPA Interrupt polarity for port A
This bit is used to invert the sensitivity of the port A
[3:0] external interrupts. It can be set and cleared
by software only when I1 and I0 of the CC register
are both set to 1 (level 3).
0: No sensitivity inversion
1: Sensitivity inversion
Bit 1 = TLIS TLI sensitivity
This bit allows to toggle the TLI edge sensitivity. It
can be set and cleared by software only when
TLIE bit is cleared.
0: Falling edge
1: Rising edge
Bit 0 = TLIE TLI enable
This bit allows to enable or disable the TLI capabil-
ity on the dedicated pin. It is set and cleared by
software.
0: TLI disabled
1: TLI enabled
Note: a parasitic interrupt can be generated when
clearing the TLIE bit.
70
IS11
IS10
IPB
IS21
IS20
IPA
TLIS
TLIE
IS11 IS10
External Interrupt Sensitivity
IPB bit =0
IPB bit =1
00
Falling edge &
low level
Rising edge
& high level
0
1
Rising edge only
Falling edge only
1
0
Falling edge only
Rising edge only
1
Rising and falling edge
IS11 IS10
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge
IS21 IS20
External Interrupt Sensitivity
IPA bit =0
IPA bit =1
00
Falling edge &
low level
Rising edge
& high level
0
1
Rising edge only
Falling edge only
1
0
Falling edge only
Rising edge only
1
Rising and falling edge
IS21 IS20
External Interrupt Sensitivity
0
Falling edge & low level
0
1
Rising edge only
1
0
Falling edge only
1
Rising and falling edge