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LIMITED-DISTANCE MODEM 56/64
4.3 Async Mode
1. Set the XMT TIMING to async mode, using S1, S2,
S3.
2. Set the data rate using S4.
3. Set the frequency allowance and the character
length according to
Table 3-1
and
Table 4-1
, using
S5, S6, and S7.
4. Set the carrier to be constantly ON or controlled
by RTS (CNT) using S8.
NOTE
Personal computers working at high speed in async mode
operate at 57.6 kbps (instead of 56 kbps). In such cases,
set the PC to
two
stop bits and strap the Modem for a
character length with
one
stop bit. Strap the rate of the
Modem to 56 kbps.
Table 4-1. Asynchronous Character Length Setting.
Start
Data
Parity
Stop
No. of Bits
Bit
Bits
Bit
1
5
NONE
2
8
1
6
NONE
1, 1.5, 2
8
1
6
ODD, EVEN
1, 1.5, 2
9
1
7
NONE
1, 1.5, 2
9
1
7
ODD, EVEN
1, 1.5, 2
10
1
8
NONE
1, 1.5, 2
10
1
8
ODD, EVEN
1, 1.5, 2
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