B&B Electronics RS-232 to J1939 Converter CE 1939STB - Manual (Page 13)

1939STB4600 Manual 11
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91 792444 – Fax +353 91 792445
RS-232 Baud Rate Change cont’d.
Baud Change; Parity, word length, stop bits.
Byte 5 (UB3)
UB3 sets the LCR register on the UART
Table 14. Byte 5 (UB3)
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Divisor
latch Set
break Set
parity Even
parity Parity
enable Stop
bits Word
length 1 Word
length 0
Bit 7 = 1 allows baud rate divisor to be changed.
0 baud rate change is blocked.
Bit seven should not be set. The setting and resetting of this bit is
handled internally.
Bit 6 = 1 forces the transmitter output to a logic 0 for alerting the remote
receiver to a line break.
0 No break condition.
Bits 5, 4, 3 work together to set parity.
Table 15. Parity Setup
Bit 5 Bit 4 Bit 3 Parity Selection
X X 0 No parity *
0 0 1 Odd parity
0 1 1 Even parity
1 0 1 Force parity “1”
1 1 1 Force parity “0”
* Setup Default Value.