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SAB 82532/SAF 82532
ASYNC Mode
Detailed Register Description
Semiconductor Group
172
07.96
XON Character (XON)
Access: read/write
address: ch-A: 24
H
ch-B: 64
H
Value after RESET: 00
H
This register is used to specify the XON character. It can be used in conjunction with the
interrupt status ISR1:XON for automatic in-band flow control (if MODE:FLON = ‘0’). The
number of significant bits is determined by the programmed character length (right
justified).
A received character is considered to be recognized as a valid XON character
– if it is correctly framed (correct length),
– if its bits match the (unmasked) ones in the XON register over the programmed
character length,
– if it has correct parity (if applicable).
Received XON characters are always stored in the receive FIFO, similar to other
characters.
XOFF Character (XOFF)
Access: read/write
address: ch-A: 25
H
ch-B: 65
H
Value after RESET: 00
H
This register is used to specify the XOFF character. It can be used in conjunction with
the interrupt status ISR1:XOFF for automatic in-band flow control (if MODE:FLON = ‘1’),
or as a special character compare register for other purposes (if MODE:FLON = ‘0’). The
number of significant bits is determined by the programmed character length (right
justified).
A received character is considered to be recognized as a valid XOFF character
– if it is correctly framed (correct length),
– if its bits match the (unmasked) ones in the XOFF register over the programmed
character length,
– if it has correct parity (if applicable).
Received XOFF characters are always stored in the receive FIFO, similar to other
characters.
7
0
XON
XON7
XON0
7
0
XOFF
XOFF7
XOFF0