Service manual

Part 2: Product Specifications BJC-4300
8) Input/ output signals:
Compatible Mode
STROBE [Input]
This signal is used to read DATA1 to DATAS. The signal becomes valid after BUSY
signal goes Low and the printer outputs an ACKNLG signal. The host computer
does not send the next signal until it receives ACKNLG signal. It is normally High,
after becoming Low. the printer receives data. When the signal remains Low, the
printer does not operate until it goes High.
DATA1 to 8 [Input]
‘Ihe printer receives data with the STROBE signal. The state of each bit of the
signal must be maintatned for at least 0.5 p’s from the rising edge of the STROBE
signal.
ACKNLG [Output]
This signal is a response signal to the STROBE signal. The host computer does not
send the next STROBE signal until this signal is sent. When the power is turned on
or the BUSY signal goes Low for the input of the INIT signal, this signal is sent
regardless of the STROBE signal.
BUSY [Output]
When this signal is High. the printer is BUSY; when Law, the printer is READY. The
signal goes high when data is received, when the printer is offline, or when an error
occurs (paper-out, paper jam).
P.E. [Output]
When the printer cannot feed paper, this signal goes High. Then BUSY signal goes
High and the SELECT and FAULT signals go Low. The signal goes Low when the
paper is set and the printer goes online. FAULT and SELECT signals then go High
from Low. If paper is not ejected [paper Jam) by executing a paper eject command.
this signal and BUSY signal go High, and SELECT and FAULT go Low. In this case,
the signals do not change even if the paper is ejected.
SELECT [Output]
The printer is SELECT when this signal is High. The printer is DESELECT when
this signal is Low. This signal goes Low when the printer is offline, when an error
occurs (paper-out, paper jam, head error, etc.).
AUTO FEED XT [Input] (Valid in LQ mode)
When this signal is Low, automatic ltne feed mode (Carriage Return and Line Feed)
is effective.
The printer judges the level of this signal only when it is turned on or is initialized
by the INIT signal.
INIT [Input]
INIT from the system resets the printer to its initial power-on state. In BJ mode, the
BUSY line goes high, and any received data is printed. In LQ mode. the BUSY line
goes high, and the print buffer is cleared. When INIT goes low. it resets the printer
to the power-on default state.
FAULT [Output]
This signal goes Low when the printer is in an error state [paper-out, paper jam, etc.).
SELECT IN [Input] (Valid in LQ mode)
When this signal is High, the DC1 and DC3 codes are valid: When Low. they are
invalid. The printer Judges the level of this signal when it is turned on or is
initialized by the INIT signal.
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