Rockwell Automation 1771-DA,D17716.5.13 U MNL 1771-DA ASCII I/O MODULE - Manual (Page 155)

Function of Control/Status Bits
Chapter 6
6Ć20
Initialization Word One
Bit Function Status
17 ACK/NAK 0* = Not used by ASCII device
1 = ACK/NAK required by device
16 Stop Bits 0* = Device generates one stop bit
1 = Device generates two stop bits
15 Parity Enable 0* = Device does not use parity bit
1 = Device generates a parity bit
14 Parity 0* = Odd
1 = Even
13 Number of Data Bits 0* = Device generates 8Ćbit data
1 = Device generates 7Ćbit data
12, 11, 10 Communication
Rate
000* = 300 baud
001 = 600 baud
010 = 1200 baud
011 = 2400 baud
100 = 4800 baud
101 = 9600 baud
110 = 110 baud
111 = 110 baud
07, 06, 05 Mode of
Transmission
000* = Full duplex with echo
001 = Full duplex without echo
010 = Simplex read
011 = Simplex write
100 = Half duplex with echo
101 = Half duplex without echo
all other codes are invalid
04, 03, 02 Mode of Operation 000* = Data mode
001 = Report Generation (RG) mode
01, 00 Number of
Initialization Words
00* = Word 1
01 = Words 1 and 2
10 = Words 1, 2, and 3
11 = Words 1, 2, 3, and 4
*Default value when you do not select that initialization word