Exchange/RJE Manual

The ETB Character

BSC Line Control

C–4 104698 Tandem Computers Incorporated

The WACK character is transmitted as shown:

ASCII line code EBCDIC line code

pad pad

SYN SYN

DLE DLE

pad pad

The ETB Character The ETB (end of transmission block) character is not used in the control state. In the

message state, the ETB character terminates a block and is immediately followed by a

block-check character (BCC). The ETB character always causes a line turnaround (the

station receiving the ETB transmits next).

The ETB character is transmitted at the end of a block as shown:

ASCII line code EBCDIC line code

text text

ETB ETB

BCC BCC

pad pad

The ETX Character The ETX (end of text) character is not used in the control state. In the message state,

the ETX character ends the last block in a job (or file). It is transmitted in place of the

ETB in the last block. The ETX does not indicate that the sending station is giving up

control of data communications line (the right to transmit); the station sending the ETX

can begin transmitting a new job as soon as the last block is acknowledged. The ETX

character always causes a line turnaround (the station receiving the ETX transmits

next).

The ETX character is transmitted at the end of the last block in a job as shown:

ASCII line code EBCDIC line code

text text

ETX ETX

BCC BCC

pad pad