4-7
STANDARD AND PTS INTERRUPTS
PTSSEL Address:
Reset State: 0004H
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. In PTS modes that use the PTSCOUNT register, hardware
clears the corresponding PTSSEL bit when PTSCOUNT reaches zero. The end-of-PTS interrupt service
routine must reset the PTSSEL bit to re-enable the PTS channel.
15 8
LA —EXTINT —RI TI SSIO1 SSIO0 —
7 0
— — AD EPA0 EPA1 EPA2 EPA3 EPA
x
15 8
LB —EXTINT —RI TI SSIO1 SSIO0 J1850ST
7 0
J1850RX J1850TX AD EPA0 EPA1 EPA2 EPA3 EPA
x
15 8
LD —EXTINT —RI TI SSIO1 SSIO0 —
7 0
— — — EPA0 EPA1 EPA2 EPA3 EPA
x
Bit
Number Function
14:0†Setting a bit causes the corresponding interrupt to be handled by a PTS microcode routine.
The PTS interrupt vector locations are as follows:
Bit Mnemonic Interrupt PTS Vector
EXTINT EXTINT pin 205CH
Reserved†— 205AH
RI SIO Receive 2058H
TI SIO Transmit 2056H
SSIO1 SSIO 1 Transfer 2054H
SSIO0 SSIO 0 Transfer 2052H
J1850ST (LB) J1850 Status 2050H
J1850RX(LB) J1850 Receive 204EH
J1850TX(LB) J1850 Transmit 204CH
AD(LA, LB) A/D Conversion Complete 204AH
EPA0 EPA Capture/Compare Channel 0 2048H
EPA1 EPA Capture/Compare Channel 1 2046H
EPA2 EPA Capture/Compare Channel 2 2044H
EPA3 EPA Capture/Compare Channel 3 2042H
EPA
x
†† Multiplexed EPA 2040H
†† PTS service is not useful for shared interrupts because the PTS cannot readily
determine the source of these interrupts.
†Bit 13 is reserved on the 8XC196L
x
devices and bits 6–8 are reserved on the 87C196LA and
83C196LD. For compatibility with future devices, write zeros to these bits.
Figure 4-5. PTS Select (PTSSEL) Register