
Interrupt Control Unit
7-24
7.3.10
Interrupt Mask Register
(IMASK, Offset 28h)
(Master Mode)
The Interrupt Mask register is a read/write register. Programming a bit in the Interrupt Mask
register has the effect of programming the MSK bit in the associated interrupt control
register. The format of the Interrupt Mask register is shown in Figure 7-13.
When a bit is set to 1 in this register, the corresponding interrupt source is masked off.
When the bit is set to 0, the interrupt source is enabled to generate an interrupt request.
Figure 7-13
Interrupt Mask Register
The IMASK register is set to 07FDh on reset.
Bits 15–11: Reserved
Bit 10: Serial Port 0 Interrupt Mask (SP0)— When set to 1, this bit indicates that the serial
port 0 interrupt is masked.
Bit 9: Serial Port 1 Interrupt Mask (SP1)—When set to 1, this bit indicates that the serial
port 1 interrupt is masked.
Bits 8–4: Interrupt Mask (INT4–INT0)—When set to 1, an INT4–INT0 bit indicates that
the corresponding interrupt is masked.
Bits 3–2: DMA Channel Interrupt Masks (D1/I6–D0/I5)—When set to 1, a D1/I6–D0/I5
bit indicates that the corresponding DMA or INT6/INT5 channel interrupt is masked.
Bit 1: Reserved
Bit 0: Timer Interrupt Mask (TMR)—When set to 1, this bit indicates that interrupt requests
from the timer control unit are masked.
15
7
0
Reserved
Res
TMR
D0/I5
D1/I6
I0
I1
I2
I3
I4
SP1
SP0
Summary of Contents for Am186 ES
Page 1: ...Am186 ES and Am188 ES User s Manual...
Page 4: ...iv...
Page 12: ...Table of Contents xii...
Page 22: ...Features and Performance 1 8...
Page 60: ...System Overview 3 28...
Page 84: ...Chip Select Unit 5 14...
Page 132: ...Timer Control Unit 8 8...
Page 166: ...Programmable I O Pins 11 6...
Page 184: ...Register Summary A 18...