OKI ML3390 01091308*01256402 ユーザーズマニュアル

製品コード

01091308*01256402

D-28

Appendix D: Interface Data

Block format: STX + Data + ETX

Data outside a block is ignored.

Error Detection:

A block was transmitted correctly

: after having received an ETX

signal an ACK signal is transmitted to the sender confirming that
the data was received without any errors.

A block was transmitted incorrectly:

after having received an ETX

signal a NAK signal is transmitted to the sender indicating that an
error occured during the transmission. On receipt of the NAK sig-
nal the block has to be transmitted again.

Display of Busy Status: None

If no error was detected:

Datenempfangs-
kreis D+ -> D-

STX

ETX

ACK

Datensende-
kreis B+ -> B-

Datenblock 2

Datenblock 3

Datenblock 1

STX

ETX

ACK

Data Receive
Buffer D+ -> D-

Data Send
Buffer B+ -> B-

If an error was detected:

Datenempfangs-
kreis D+ -> D-

STX

ETX

NAK

Datensende-
kreis B+ -> B-

Datenblock 1

STX

ETX

NAK

Data Receive
Buffer D+ -> D-

Data Send
Buffer B+ -> B-

Data for Bitmap Graphics

The above mentioned timing diagrams are only valid as long as the
printer is in text mode. The start character STX and the stop charac-
ter ETX are only interpreted as control characters of the CBD trans-
mission protocol in text mode. Please note the following if you
want to print bitmap graphics:

Centronics Blocked
Duplex (CBD)
Protocol

Data Block 1

Data Block 2

Data Block 3

Data Block 1