Denso BHT-7000 User Manual

92

The control characters are classified into two groups:  transmission control characters
and text control characters.

The transmission control characters listed below are used to compose transmission
control sequences in phases 1 through 3.

Symbol

Value

Meaning

Function

EOT

04h

End Of Transmission

Releases a data link (Phase 3).

Requests  abort  of  transmission
(Phase 2).

ENQ

05h

Enquiry

Requests establishment of a data link

(Phase 1).

Prompts the receiver to respond to
the sent text (Phase 2).

ACK

06h

Acknowledge

Acknowledgment  response  to  ENQ
(Phase 1).

Acknowledgment  response  to  text
(Phase 2).

Acknowledgment  response  to  EOT
(Phase 3).

NAK

15h

Negative Acknowledge

Negative acknowledgment response
to ENQ (Phase 1).

Negative acknowledgment response
to text (Phase 2).

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The BHT-7000 uses the non-transparent mode which handles the control characters
and codes (e.g., STX, ETX, and SOH) as starting or ending markers and does not
allow them to be transmitted as normal data in the transmission texts.