XR68C681 Datasheet, PDF (62/75 Pages) Exar Corporation – CMOS Dual Channel UART (DUART)

XR68C681
I. PROGRAMMING
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Table 1 $ % '%   '  % +    "
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 % ' ' # - " '  -%  -(%%
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' -(%
Bit 7
Rx RTS
Control
 J 8
 J E%
Bit 6
Bit 5
Rx Int Select Error Mode
J5E
J ::
J

J *'3
Bit 4
Bit 3
Parity Mode Select
 J A( ,(&
 J ' ,(&
 J 8 ,(&
 J ( $
Bit 2
Parity Select
 J 2
 J $$
Bit 1
Bit 0
Number of Bits/Char.
 J 6
 J /
 J @
 J <
Table 20. Mode Registers 1: MR1A, MR1B
Bit 7
Bit 6
Channel Mode
 J 8
 J  2' 
 J :' :
 J  :
Bit 5
Tx RTS
Control
 J 8
 J E%
Bit 4
CTS Enable
Tx
 J 8
 J E%
Bit 3
Bit 2
Bit 1
Stop Bit Length
Bit 0
 J 6/1
 J /6
 J /<<
1 J @6
= J <1
6 J <@6
/ J 1<
@ J 
< J 6/1
 J /6
J /<<
* J @6

J <1
 J <@6
2 J 1<
J 
Table 21. Mode Register 2: MR2A, MR2B
Bit 7
Bit 6
Bit 5
'(
'3 '
 Table 6
Bit 4
Bit 3
Bit 2
Bit 1
 %(
'3 '
 Table 6
Bit 0
Table 22. Clock Select Registers: CSRA, CSRB
 
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