Intel 8XC196NT User Manual page 207

8XC196NT USER'S MANUAL
SSIO x _CON (Continued)
x = 0–1
The synchronous serial control x (SSIO x _CON) registers control the communications mode and
handshaking. The two least-significant bits indicate whether an overflow or underflow has occurred
and whether the channel is ready to transmit or receive.
7
M/S# T/R#
Bit Bit
Number Mnemonic
3 STE
2 ATR
1 OUF
0 TBS
†
The M/S# and T/R# bits specify four possible configurations: master transmitter, master receiver,
slave transmitter, or slave receiver.
Figure 8-6. Synchronous Serial Control x (SSIO x _CON) Registers (Continued)
8-12
TRT THS
Single Transfer Enable
Enables and disables transfer of a single byte. Unless ATR is set, STE is
automatically cleared at the end of a transfer. The THS, STE, and ATR
bits must be set for handshaking modes.
0 = disable transfers
1 = allow transmission or reception of a single byte
Automatic Transfer Re-enable
Enables and disables subsequent transfers. The THS, STE, and ATR bits
must be set for handshaking modes.
0 = allow automatic clearing of STE; disable subsequent transfers
1 = prevent automatic clearing of STE; allow transfer of next byte
Overflow/Underflow Flag
Indicates whether an overflow or underflow has occurred. An attempt to
access SSIO x _BUF during a byte transfer sets this bit.
For the master (M/S# = 1)
0 = no overflow or underflow has occurred
1 = the core attempted to access SSIO x _BUF during the current transfer
For the slave (M/S# = 0)
0 = no overflow or underflow has occurred
1 = the core attempted to access SSIO x _BUF during the current transfer
or the master attempted to clock data into or out of the slave's
SSIO x _BUF before the buffer was available
Transceiver Buffer Status
Indicates the status of the channel's SSIO x _BUF.
For the transmitter (T/R# =1)
0 = SSIO x _BUF is full; waiting to transmit
1 = SSIO x _BUF is empty; buffer available
For the receiver (T/R# = 0)
0 = SSIO x _BUF is empty; waiting to receive
1 = SSIO x _BUF is full; data available
Address:
Reset State:
STE ATR
Function
1FB1H, 1FB3H
00H
0
OUF TBS