Intel 8XC196MH, 8XC196MD, 8XC196MC manual Asio Transmit Mode PTSCBs, PTSCB1 PTSCB2

8XC196MC, MD, MH USER’S MANUAL

5.Initialize and enable the timer; select up counting, internal clock, and prescaler disabled.

— Set T1CONTROL bits 6 and 7 (Figure 11-8 on page 11-16).

6.Initialize the PTSCB as shown in Table 5-15.

Table 5-15. ASIO Transmit Mode PTSCBs

PTSCB1	PTSCB2
PTSVEC (H) = pointer to PTSCB2	Unused
PTSVEC (L) = pointer to PTSCB2	SAMPTIME = unused
BAUD (H) = 01H (9600 baud at 16 MHz)	DATA (H) = unused
BAUD (L) = A0H (9600 baud at 16 MHz)	DATA (L) = nnH (8 data bits)
EPAREG (H) = 1FH (EPA0_TIME)	PTSCON1 = 21H (enable odd parity)
EPAREG (L) = 42H (EPA0_TIME)	PORTMASK = 01H (P2.0 = TXD)
PTSCON = 60H (ASIO transmit mode)	PORTREG (H) = 1FH (P2_REG)
PTSCOUNT = 0AH (8 data bits, 1 parity, & 1 stop	PORTREG (L) = D4H (P2_REG)
bit)

7.Enable EPA0 interrupt.

—Set INT_MASK.2.

8.Load the number of bytes to transmit into the user_defined transmit count register (T_COUNT) and clear the user-defined transfer-done flag (TXDDONE).

—LD T_COUNT, #16

—CLRB TXDDONE

9.Select PTS service for EPA0.

—Set PTSSEL.2.

10.Set-up the transmission start bit.

—Clear P2.0.

11.Set-up EPA0 as a compare-only channel.

—Set EPA0_CON.6 (Figure 11-10 on page 11-19).

12.Start the operation of the EPA0 channel by writing the time of the first interrupt to EPA0_TIME. To set-up the correct value, add the baud_value (1A0H) to the current TIMER1 value and store the result in EPA0_TIME. The baud_value determines the time to the first PTS interrupt. When the interrupt occurs, the PTS transmits the first data bit. The baud_value of 1A0H selects a baud rate of 9600.

13.Enable the PTS and conventional interrupts.

— Use the EI instruction to enable all standard interrupts and the EPTS instruction to enable the PTS.

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