Citizen Systems CBM-910 Type II user manual Error Detection, Receiving Control and Buffering

6.5Error Detection

●Communication error

• Parity error

Parity error occurs when parity check is specified and parity is not observed in the even and odd parity checks.

• Framing error

When space state detected on detection of stop bit.

• Overrun error

When next following data having been transferred to receiving buffer register regardless of presence of data in that receiving buffer register.

On occurrence of the above error, convert data at the time of occurrence into ■ (7FH) to print it out.

RECEIVING CONTROL AND BUFFERING

This equipment controls, on receipt of print data, receiving (DTR Control) in one-word unit. If the host disregards DTR and carries out data transmission at this time, over- run of receiving data may be resulted. This state should be avoided on the host’s responsibility. (The data discharging type host cannot follow this.) This is applicable when the host adopts a double buffer type transmitter.

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