STANDARD AND PTS INTERRUPTS

PTS Serial I/O Mode Control Block 2 (8XC196MC, MD)

The PTS control block 2 contains pointers to both the port register (PORTREG) and the data register (DATA). It also contains a 16-bit value that is used to calculate the sample time for asynchronous receptions when majority sampling is selected (SAMPTIME), a control register (PTSCON1), and a 16- bit value that is used to select the port signal that functions as the TXD or RXD signal (PORTMASK).

Unused

SAMPTIME

DATA (H)

DATA (L)

7

 

 

 

 

 

 

 

 

 

0

0

0

0

 

0

 

0

 

0

0

0

7

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sample Time Value

 

 

 

15

 

 

 

 

 

 

 

 

 

8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Data Register (high byte)

 

 

 

7

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Data Register (low byte)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PTSCON1 (Synch)

PTSCON1 (Asynch)

7

0

0

0

0

7

 

 

 

 

 

 

 

0

RPAR

PEN

0

7

 

 

 

0

0

0

TRC

0

 

 

 

 

0

0

0

FE

TPAR

 

 

 

 

0

PORTMASK

PORTREG (H)

PORTREG (L)

 

Port Mask Register

15

0

 

 

 

Port Address Pointer (high byte)

7

0

Port Address Pointer (low byte)

Register

Location

 

Function

 

 

 

SAMPTIME

PTSCB2 + 6

Sample Time Value

 

 

This register controls the time between samples during

 

 

asynchronous receive mode when majority sampling is selected.

 

 

Use the following formula to calulate the value to load into the

 

 

SAMPTIME register.

 

 

 

TS A M × FX T A L 1

 

 

Sample_ time = ------------------------------------------9

 

 

 

2

 

 

where:

 

 

 

Sample_time is an integer, 1–31, that is loaded into the

 

 

 

SAMPTIME register

 

 

TSAM

is the desired time between samples, in µs

 

 

FXTAL1

is the input frequency on XTAL1, in MHz

Figure 5-20. PTS Control Block 2 – Serial I/O Mode

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Intel 8XC196MD PTS Serial I/O Mode Control Block 2 8XC196MC, MD, Port Mask Register, Port Address Pointer high byte