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SYNTAX [<LABEL>] FORT <constant>
OPERANDS Constant = 0 or 1
EXECUTION (PC) + 1 . PC
Constant . format (FO) status bit
Affects FO.
DESCRIPTION The format (FO) status bit is loaded by the instruction with
the LSB specified in the instruction. The FO bit is used to
control the formatting of the transmit and receive shift
registers of the serial port. If FO = 0, the registers are
configured to receive/transmit 16-bit words. If FO = 1, the
registers are configured to receive/transmit 8-bit bytes. FO
is set to zero on a reset.
WORDS 1
ENCODING 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+-----------------------------------------------+
|1 1 0 0 1 1 1 0 0 0 0 0 1 1 1|FO |
+-----------------------------------------------+
CYCLES
+------------------------------------------------+
| Cycle Timings for a Single Instruction |
|------------------------------------------------|
| PI/DI | PI/DE | PE/DI | PE/DE | PR/DI | PR/DE |
|-------+-------+-------+--------+-------+-------|
'20 | 1 | 1 | 1+p | 1+p | - | - |
|-------+-------+-------+--------+-------+-------|
'C25 | 1 | 1 | 1+p | 1+p | 1 | 1 |
|------------------------------------------------|
| Cycle Timings for a Repeat Instruction |
|------------------------------------------------|
'20 | n | n | n+p | n+p | - | - |
|-------+-------+-------+--------+-------+-------|
'C25 | n | n | n+p | n+p | n | n |
+------------------------------------------------+
EXAMPLE FORT 1 The FO status bit is loaded with 1, making the bit
length of the serial port 8 bits.