Citizen Systems CBM920II user manual Error Detection, Receiving Control and Buffering

(2)TTL circuit (PE/RESET/FAULT) Input (RESET)

The input signal level is TTL level. “HIGH” level: 2.4 V MIN “LOW” level: 0.4 V MAX

5K

RESET

104 (7406 compatible)

Output (RE/FAULT)

The output signal level is TTL level. “HIGH” level: 2.4 V MIN

“LOW” level: 0.4 V MAX

PE/FAULT

10K

(HC05 compatible)

6.5 Error Detection

This printer detects the following communication errors in the data communication of serial interface. When any error occurs, the printer converts (or may ignore in some case) the data at the occurrence of the error to the characters set by the memory switch and then prints the characters.

•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

This error occurs when next data is transferred to receiving buffer though input buffer is full of data.

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.)

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