Table 7-15. Interrupts—Priority and Action to Clear Requests

Priority

Interrupt Source

Action Required to Clear the Interrupt

 

 

 

Highest

External 1

Automatically cleared by the interrupt acknowledge.

 

 

 

 

External 0

Automatically cleared by the interrupt acknowledge.

 

 

 

 

Periodic (2 kHz)

Read the status from the GCSR.

 

 

 

 

Quadrature Decoder

Read the status from the QDCSR.

 

 

 

 

Timer B

Read the status from the TBSR.

 

 

 

 

Timer A

Read the status from the TASR.

 

 

 

 

Input Capture

Read the status from the ICCSR.

 

 

 

 

Slave Port

Rd: Read the data from the SPD0R, SPD1R or SPD2R.

 

Wr: Write data to the SPD0R, SPD1R, SPD2R or write a

 

 

dummy byte to the SPSR.

 

 

 

 

 

Rx: Read the data from the SEDR or SEAR.

 

Serial Port E

Tx: Write data to the SEDR, SEAR, SELR or write a dummy

 

 

byte to the SESR.

 

 

 

 

Serial Port F

Rx: Read the data from the SFDR or SFAR.

 

Tx: Write data to the SFDR, SFAR, SFLR or write a dummy

 

 

byte to the SFSR.

 

 

 

 

Serial Port A

Rx: Read the data from the SADR or SAAR.

 

Tx: Write data to the SADR, SAAR, SALR or write a dummy

 

 

byte to the SASR.

 

 

 

 

 

Rx: Read the data from the SBDR or SBAR.

 

Serial Port B

Tx: Write data to the SBDR, SBAR, SBLR or write a dummy

 

 

byte to the SBSR.

 

 

 

 

Serial Port C

Rx: Read the data from the SCDR or SCAR.

 

Tx: Write data to the SCDR, SCAR, SCLR or write a dummy

 

 

byte to the SCSR.

 

 

 

Lowest

Serial Port D

Rx: Read the data from the SDDR or SDAR

Tx: Write date to the SDDR, SDAR, SDLR or write a dummy

 

 

byte to the SDSR

 

 

 

In the case of the external interrupts the only action that will clear the interrupt request is for the interrupt to take place, which automatically clears the request. A special action must be taken in the interrupt service routine for the other interrupts.

98

Rabbit 3000 Microprocessor

Page 107
Image 107
Jameco Electronics 2000, 3000 manual Interrupts-Priority and Action to Clear Requests