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ST90158 - INTERRUPTS
INTERRUPT REGISTERS
(Cont’d)
EXTERNAL INTERRUPT PENDING REGISTER
(EIPR)
R243 - Read/Write
Register Page: 0
Reset value: 0000 0000 (00h)
Bit 7 =
IPD1
:
INTD1
Interrupt Pending bit
Bit
6 =
IPD0
:
INTD0
Interrupt Pending bit
Bit 5 =
IPC1
:
INTC1 Interrupt Pending bit
Bit 4 =
IPC0
:
INTC0
Interrupt Pending bit
Bit 3 =
IPB1
:
INTB1
Interrupt Pending bit
Bit 2 =
IPB0
:
INTB0 Interrupt Pending bit
Bit 1 =
IPA1
:
INTA1
Interrupt Pending bit
Bit 0 =
IPA0
:
INTA0 Interrupt Pending bit
These bits are set by hardware on occurrence of a
trigger event (as specified in the EITR register)
and are cleared by hardware on interrupt acknowl-
edge. They can also be set by software to imple-
ment a software interrupt.
0: No interrupt pending
1: Interrupt pending
EXTERNAL INTERRUPT MASK-BIT REGISTER
(EIMR)
R244 - Read/Write
Register Page: 0
Reset value: 0000 0000 (00h
)
Bit 7 =
IMD1
:
INTD1 Interrupt Mask
Bit 6 =
IMD0
:
INTD0 Interrupt Mask
Bit 5 =
IMC1
:
INTC1 Interrupt Mask
Bit
4 =
IMC0
:
INTC0 Interrupt Mask
Bit 3 =
IMB1
:
INTB1 Interrupt Mask
Bit 2 =
IMB0
:
INTB0 Interrupt Mask
Bit
1 =
IMA1
:
INTA1 Interrupt Mask
Bit 0 =
IMA0
:
INTA0 Interrupt Mask
These bits are set and cleared by software.
0: Interrupt masked
1: Interrupt not masked (an interrupt is generated if
the IPxx and IEN bits = 1)
EXTERNAL INTERRUPT PRIORITY LEVEL
REGISTER (EIPLR)
R245 - Read/Write
Register Page: 0
Reset value: 1111 1111 (FFh
)
Bit 7:6 =
PL2D, PL1D:
INTD0, D1 Priority Level.
Bit 5:4 =
PL2C, PL1C
:
INTC0, C1 Priority Level.
Bit 3:2 =
PL2B, PL1B
:
INTB0, B1 Priority Level.
Bit 1:0 =
PL2A, PL1A
:
INTA0, A1 Priority Level.
These bits are set and cleared by software.
The priority is a three-bit value. The LSB is fixed by
hardware at 0 for Channels A0, B0, C0 and D0 and
at 1 for Channels A1, B1, C1 and D1.
7
0
IPD1
IPD0
IPC1
IPC0
IPB1
IPB0
IPA1
IPA0
7
0
IMD1 IMD0 IMC1 IMC0 IMB1 IMB0 IMA1 IMA0
7
0
PL2D PL1D PL2C PL1C PL2B PL1B PL2A PL1A
PL2x
PL1x
Hardware
bit
0
1
0
1
0
1
0
1
Priority
0
0
0 (Highest)
1
2
3
4
5
6
7 (Lowest)
0
1
1
0
1
1
9