STANDARD AND PTS INTERRUPTS

INT_PEND

Address:

0009H

 

Reset State:

00H

When hardware detects an interrupt request, it sets the corresponding bit in the interrupt pending (INT_PEND or INT_PEND1) registers. When the vector is taken, the hardware clears the pending bit. Software can generate an interrupt by setting the corresponding interrupt pending bit.

 

 

7

 

 

 

 

 

 

 

 

 

0

LA

 

 

AD

EPA0

 

EPA1

EPA2

EPA3

 

EPAx

 

 

7

 

 

 

 

 

 

 

 

 

0

LB

 

 

 

 

 

 

 

 

 

 

 

 

J1850RX

J1850TX

AD

EPA0

 

EPA1

EPA2

EPA3

 

EPAx

 

 

7

 

 

 

 

 

 

 

 

 

0

LD

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EPA0

 

EPA1

EPA2

EPA3

 

EPAx

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

 

 

 

Function

 

 

 

 

Number

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7:0

Any set bit indicates that the corresponding interrupt is pending. The interrupt bit is cleared

 

when processing transfers to the corresponding interrupt vector.

 

 

 

 

 

Bit Mnemonic

Interrupt Description

 

 

 

 

 

 

 

J1850RX

 

J1850 Receive (LB only)

 

 

 

 

 

 

 

J1850TX

 

J1850 Transmit (LB only)

 

 

 

 

 

 

 

AD

 

A/D Conversion Complete (LA, LB)

 

 

 

 

 

 

EPA0

 

EPA Capture/Compare Channel 0

 

 

 

 

 

 

EPA1

 

EPA Capture/Compare Channel 1

 

 

 

 

 

 

EPA2

 

EPA Capture/Compare Channel 2

 

 

 

 

 

 

EPA3

 

EPA Capture/Compare Channel 3

 

 

 

 

 

 

EPAx††

 

Shared EPA Interrupt

 

 

 

 

 

 

††

EPA 6–9 capture/compare channel events, EPA 0–1 compare channel events†††

, EPA

 

 

0–3 and 8–9 capture/compare overruns, and timer overflows can generate this shared

 

 

interrupt. Write the EPA mask registersto enable the interrupt sources; read the EPA

 

 

pending registers to determine which source caused the interrupt.

 

 

 

 

†††

87C196LA, LB only.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bits 6–7 are reserved on the 87C196LA, and bits 5–7 are reserved on the 83C196LD. For compatibility with future devices, write zeros to these bits.

Figure 4-3. Interrupt Pending (INT_PEND) Register

4-5

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Intel 87C196CA, 8XC196Jx, 8XC196Lx, 8XC196Kx user manual Interrupt Pending Intpend Register