8XC196MC, MD, MH USER’S MANUAL

End-Of-PTS Interrupt

Save Critical Data

Disable EPA Channel

Clear Interrupt Request Bit

Save Received Data

R_COUNT = R_COUNT - 1

R_COUNT = 0?

Y

N

Set-up next data reception

-Clear DATA register

-Reload PTSCOUNT and PTSCON1 registers

-Select PTS service for EPA channel

-Re-initialize the EPA channel

Load Critical Data

Return

RXDDONE = 1

A3275-01

Figure 5-24. Synchronous SIO Receive Mode — End-of-PTS I nterrupt Routine Flowchart

5.6.6.3Asynchronous SIO Transmit Mode Example

In asynchronous serial I/O (ASIO) transmit mode, an EPA channel controls the transmission baud rate by generating an interrupt whenever a match occurs between the EPA event-time register and a timer register. The PTS shifts a data bit out onto a port pin that is configured to function as the Transmit Data signal (TXD) when the selected EPA channel generates a compare interrupt (Fig- ure 5-25). In ASIO transmit mode, the PTS automatically transmits up to 16 bits (data + 1 optional parity + 1 stop bit). The maximum number of data bits is 14 with parity, or 15 without.

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Intel 8XC196MC, 8XC196MD, 8XC196MH manual Rxddone =