Programming The Ssio Port; Configuring The Ssio Port Pins; Programming The Baud Rate And Enabling The Baud-Rate Generator - Intel 8XC196NT User Manual

8.5

PROGRAMMING THE SSIO PORT

To use the SSIO port, you must configure the port pins to serve as special-function signals, then
set up the SSIO channels.
8.5.1

Configuring the SSIO Port Pins

Before you can use the SSIO port, you must configure the necessary port 6 pins to serve as their
special-function signals. Handshaking mode requires that both the master and slave SCx pins be
configured as open-drain outputs. (This configuration requires external pull-up resistors.) Table
8-1 on page 8-2 lists the pins associated with the SSIO port, and Table 8-2 lists the port configu-
ration registers. See Chapter 6 for configuration details.
8.5.2

Programming the Baud Rate and Enabling the Baud-rate Generator

The SSIO_BAUD register (Figure 8-5 on page 8-10) defines the baud rate and enables the baud-
rate generator. This register acts as a control register during write operations and as a down-
counter monitor during read operations. The baud-rate generator provides an internal clock to the
transceiver channels. The frequency ranges from F
frequency, this corresponds to a range from 2.5 MHz to 19.531 kHz. Table 8-3 lists SSIO_BAUD
values for common baud rates.
SYNCHRONOUS SERIAL I/O (SSIO) PORT
/8 to F /1024. With a 20-MHz oscillator
OSC OSC
8-9