
Interrupt Control Unit
7-30
7.4.4
Interrupt Status Register
(INTSTS, Offset 30h)
(Slave Mode)
The Interrupt Status register controls DMA activity when nonmaskable interrupts occur and
indicates the current interrupt status of the three timers.
Figure 7-19
Interrupt Status Register
The INTSTS register is set to 0000h on reset.
Bit 15: DMA Halt (DHLT)—When set to 1, halts any DMA activity. Automatically set to 1
when nonmaskable interrupts occur and reset when an IRET instruction is executed.
Bits 14–3: Reserved
Bits 2–0: Timer Interrupt Request (TMR2–TMR0)—When set to 1, indicates the
corresponding timer has an interrupt request pending.
15
7
0
Reserved
TMR2
TMR1
TMR0
DHLT
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...