Detection System For Error; Input Control And Buffering - Citizen iDP-562 Series User Manual

5.6.2 Detection System for Error

The printer detects PARITY and FRAMING ERROR. ALARM (ALM) LAMP informs the user error occurrence.
When any error is detected, the printer deletes the wrong DATA and waits for new DATA, ALM LAMP can be put
out by depressing SEL switch.
Framing Error
Framing error occurs when SPACE signal is checked out at STOP BIT. ALM LAMP informs the user this error
and the wrong data is neglected by the printer.
Parity Error
Parity check function works only when the user designates it. ALM LAMP informs you this error. The wrong data
is neglected by the printer.
Other Errors
When any trouble is found out at the printer, ALM LAMP informs the user this error. In this case, FAULT signal is
SPACE, DTR signal is BUSY and the machine becomes deselect condition.
ALARM condition will be released by depressing SEL Switch after removing the trouble at the printer.
The machine is now SELECT condition and starts to input DATA.

5.6.3. Input Control and Buffering

DATA receipt is controlled by each character. In case the connected computer neglects this regulation and transfers
DATA during BUSY, "OVER RUN ERROR" occurs. To avoid this error, DATA should be transferred after
confirming the printer is at "READY". However, if the connected computer has double buffer system, the printer
can accept up to 2 words.
(1) Input Control to Signal Buffer
BUSY signal is SPACE when the printer is ready to accept DATA (signal level of BUSY can be changed by
H/W)
After receiving START BIT from the computer, (1 / 2 START BIT), BUSY signal becomes MARK level.
CITIZEN 15
iDP-562 User's Manual