
Interrupt Control Unit
7-31
7.4.5
Interrupt Request Register
(REQST, Offset 2Eh)
(Slave Mode)
The internal interrupt sources have interrupt request bits inside the interrupt controller. A
read from this register yields the status of these bits. The Interrupt Request register is a
read-only register. The format of the Interrupt Request register is shown in Figure 7-20.
For internal interrupts (D1/I6, D0/I5, TMR2, TMR1, and TMR0), the corresponding bit is set
to 1 when the device requests an interrupt. The bit is reset during the internally generated
interrupt acknowledge.
Figure 7-20
Interrupt Request Register
The REQST register is set to 0000h on reset.
Bits 15–6: Reserved
Bits 5–4: Timer 2/Timer 1 Interrupt Request (TMR2–TMR1)—When set to 1, these bits
indicate the state of any interrupt requests from the associated timer.
Bits 3–2: DMA Channel Interrupt Request (D1/I6–D0/I5)—When set to 1, D1/I6–D0/I5
indicate that the corresponding DMA channel or INT5/INT6 has an interrupt pending.
Bit 1: Reserved
Bit 0: Timer 0 Interrupt Request (TMR0)—When set to 1, this bit indicates the state of
an interrupt request from timer 0.
15
7
0
Reserved
D0/I5
D1/I6
TMR1
TMR2
Res
TMR0
Содержание Am186 ES
Страница 1: ...Am186 ES and Am188 ES User s Manual...
Страница 4: ...iv...
Страница 12: ...Table of Contents xii...
Страница 22: ...Features and Performance 1 8...
Страница 60: ...System Overview 3 28...
Страница 84: ...Chip Select Unit 5 14...
Страница 132: ...Timer Control Unit 8 8...
Страница 166: ...Programmable I O Pins 11 6...
Страница 184: ...Register Summary A 18...