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2 error detection, 3 data reception control, 4 buffering – Citizen Systems iDP3240 User Manual

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7.3.2 Error Detection

Detection of parity errors, framing errors, and overrun errors is provided with this
printer. When an error is detected, the data containing the error is stored in the
buffer as a “?”.

(1) Framing error

If a space state is detected at the timing of stop bit detection, this indicates that
an error has occurred. The data containing the error is stored in the buffer as a
“?”.

(2) Parity error

With parity check specified, when data is parity-checked and an error is detected,
the data containing the error is stored in the buffer as a “?”.

(3) Overrun error

If an overrun error is detected, the data containing the error is stored in the buffer
as a “?”.

7.3.3 Data Reception Control

With DTR/DSR control selected, when DTR signal becomes “Low”, the printer can
receive data from the host computer, but when it is “High”, the printer cannot
receive data. With DTR/DSR control not selected, after sending out X-ON, the
printer receives data from the host computer, but cannot receive data from the
host computer after X-OFF is sent out.

7.3.4 Buffering

When data is transferred to the input buffer, DTR and TD signals are used as
control signals.
• Refer to 7.3.1 (2) for DTR signal.
• Refer to 7.3.1 (3) for TD signal.