XR17V358 Datasheet, PDF (54/68 Pages) Exar Corporation – HIGH PERFORMANCE OCTAL PCI EXPRESS UART

XR17V358
PRELIMINARY
HIGH PERFORMANCE OCTAL PCI EXPRESS UART
REV. P1.0.2
TABLE 17: PARITY PROGRAMMING
LCR BIT [5]
X
0
LCR BIT [4]
X
0
LCR BIT [3]
0
1
PARITY SELECTION
No parity
Odd parity
0
1
1
0
1
1
LCR[4]: TX and RX Parity Select
1
Even parity
1
Force parity to mark, “1”
1
Forced parity to space, “0”
If the parity bit is enabled with LCR bit [3] set to a logic 1, LCR bit [4] selects the even or odd parity format.
• Logic 0 = ODD Parity is generated by forcing an odd number of logic 1’s in the transmitted character. The
receiver must be programmed to check the same format (default).
• Logic 1 = EVEN Parity is generated by forcing an even the number of logic 1’s in the transmitted character.
The receiver must be programmed to check the same format.
LCR[3]: TX and RX Parity Select
Parity or no parity can be selected via this bit. The parity bit is a simple way used in communications for data
integrity check. See Table 17 above for parity selection summary.
• Logic 0 = No parity.
• Logic 1 = A parity bit is generated during the transmission while the receiver checks for parity error of the
data character received.
LCR[2]: TX and RX Stop-bit Length Select
The length of stop bit is specified by this bit in conjunction with the programmed word length.
BIT [2]
0
1
1
WORD
LENGTH
5,6,7,8
5
6,7,8
STOP BIT LENGTH
(BIT TIME(S))
1 (default)
1-1/2
2
LCR[1:0]: TX and RX Word Length Select
These two bits specify the word length to be transmitted or received.
BIT [1]
BIT [0]
WORD LENGTH
0
0
5 (default)
0
1
6
1
0
7
1
1
8
4.8 Modem Control Register (MCR) - Read/Write
The MCR register is used for controlling the modem interface signals or general purpose inputs/outputs.
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