Intel 8XC196NP, 80C196NU manual Programming Considerations for Multiplexed Interrupts, Ptssel

Models: Microcontroller 80C196NU 8XC196NP

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STANDARD AND PTS INTERRUPTS

PTSSEL

Address:

0004H

 

Reset State:

0000H

The PTS select (PTSSEL) register selects either a PTS microcode routine or a standard interrupt service routine for each interrupt request. Setting a bit selects a PTS microcode routine; clearing a bit selects a standard interrupt service routine. When PTSCOUNT reaches zero, hardware clears the corresponding PTSSEL bit. The PTSSEL bit must be set manually to re-enable the PTS channel.

15

EXTINT3

EXTINT2

OVR2_3

7

 

 

 

 

 

 

 

EPA0

RI

TI

EXTINT1

 

 

 

 

8

OVR0_1

EPA3

EPA2

EPA1

 

 

 

 

0

EXTINT0

OVRTM2

OVRTM1

 

 

 

 

Bit

 

Function

 

Number

 

 

 

 

 

 

 

15, 2

Reserved; for compatibility with future devices, write zero to this bit.

 

 

14:3

Setting a bit causes the corresponding interrupt to be handled by a PTS microcode

1:0

routine.

 

 

 

The PTS interrupt vector locations are as follows:

 

 

Bit Mnemonic

Interrupt

PTS Vector

 

EXTINT3

EXTINT3 pin

FF205CH

 

EXTINT2

EXTINT2 pin

FF205AH

 

OVR2_3

EPA Capture Channel 2 or 3 Overrun

FF2058H

 

OVR0_1

EPA Capture Channel 0 or 1 Overrun

FF2056H

 

EPA3

EPA Capture/Compare Channel 3

FF2054H

 

EPA2

EPA Capture/Compare Channel 2

FF2052H

 

EPA1

EPA Capture/Compare Channel 1

FF2050H

 

EPA0

EPA Capture/Compare Channel 0

FF204EH

 

RI

SIO Receive

FF204CH

 

TI

SIO Transmit

FF204AH

 

EXTINT1

EXTINT1 pin

FF2048H

 

EXTINT0

EXTINT0 pin

FF2046H

 

OVRTM2

Timer 2 Overflow/ Underflow

FF2042H

 

OVRTM1

Timer 1 Overflow/ Underflow

FF2040H

PTS service is not recommended because the PTS cannot determine the source of shared interrupts.

Figure 6-4. PTS Select (PTSSEL) Register

6.5.1Programming Considerations for Multiplexed Interrupts

An overrun on the EPA capture compare channels can generate the multiplexed capture overrun interrupts (OVR0_1 and OVR2_3). Write to the EPA_MASK (Figure 10-11 on page 10-22) reg- ister to enable or disable the multiplexed interrupt sources and the INT_MASK1 register to en- able or disable the OVR0_1 and OVR2_3 interrupts.

PTS service is not recommended for multiplexed interrupts because it cannot determine the inter- rupt source.

6-11

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Intel 8XC196NP, 80C196NU Programming Considerations for Multiplexed Interrupts, Ptssel, Bit Mnemonic Interrupt PTS Vector