Serial Interface

Protocols

X-ON/X-OFF Protocol

Control is by output of the codes for the data transmission request signal X-ON (11 Hex) and the data transmission stop signal X-OFF (13 Hex). When sending the printer's status to the Host, this is sent irrespective of the level of the DSR signal.

Conditions for Output of the X-ON Code

When all errors have been cleared.

When the remaining buffer capacity is greater than Non bytes.

After the power is turned on, when in the Ready to Receive state.

Conditions for Output of the X-OFF Code

When the printer has generated an error and has switched from Online to Offline.

When the remaining buffer capacity is Noff bytes or less.

*Even if the X-ON/X-OFF code output conditions are established, the same code is not output two times in succession. However, times when the power is turned ON are expected.

*When the menu setting error handshake is disabled, XON/XOFF is not output when the error status changes.

DTR/DSR Protocol

Control is by the level of the DTR signal, Ready “High” /Busy “Low”.

If the printer's status is sent to the Host, it is sent when DSR is “High.” If DSR is “Low,” the printer waits until it goes “High.”

Conditions for the DTR Signal to become Ready “High”

When all the errors have been cleared.

When the remaining buffer capacity is greater than Non bytes.

After the power is turned on, when in the Ready to Receive state.

Conditions for the DTR Signal to become Busy “Low”

When the printer has generated an error and has switched from Online to Offline.

When the remaining buffer capacity is Noff bytes or less.

*When the menu setting error handshake is disabled, the DTR signal does not change.

Conditions for Non and Noff (Units: Bytes)

When there is an 8 KB buffer. Non=2048

Noff=1024

When there is a one line buffer. Non= 20

Noff=10

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CBM America CBM-262 user manual Protocols