8.3.7Interrupt Status Register (INTSTS, Offset 30h) (Master Mode)

The Interrupt Status (INTSTS) Register indicates the interrupt request status of the three timers.

Figure 8-10 Interrupt Status Register (INTSTS, offset 30h)

15

7

0

Reserved

DHLT

TMR2

 

TMR0

 

TMR1

Bit 15: DMA Halt (DHLT)—When set to 1, halts any DMA activity. This bit is automatically set to 1 when nonmaskable interrupts occur and is reset when an IRET instruction is executed. Time-critical software, such as interrupt handlers, can modify this bit directly to inhibit DMA transfers. Because of the function of this register as an interrupt request register for the timers, the DHLT bit should not be modified by software when timer interrupts are enabled.

Bits 14–3: Reserved

Bits 2–0: Timer Interrupt Request (TMR2–TMR0) —When set to 1, these bits indicate that the corresponding timer has an interrupt request pending. (Note that the timer TMR bit in the REQST Register is the logical OR of these timer interrupt requests.)

Interrupt Control Unit

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AMD Am188TMER Interrupt Status Register INTSTS, Offset 30h Master Mode, Interrupt Status Register INTSTS, offset 30h