Canon MultiPASS C50, Service Manual

Page: 232 / 272

BUSY
When the printer makes BUSY high, it cannot receive data. The BUSY line goes high in response to a -
STROBE pulse. This line remains high until the data are read. BUSY is also high under the following
conditions:
• The receive buffer is full of data.
• The printer receives an -INIT signal.
• A printer error condition, such as out-of-paper, occurs.
P.E. (Paper End)
The printer sets P. E. high when it is out of paper or when a paper jam occurs. P. E. remains high until
the operator loads paper and presses the
RESUME
button.
SELECT
When the printer is ready, it sets the SELECT line high. The SELECT line goes low when:
• An error condition, such as out-of-paper, occurs.
• The printer receives the Printer Deselect command. It ignores all incoming data except DC1, which
returns the printer to a selected state.
-AUTO FEED XT
If this signal is low when the printer is initializing, the printer automatically feeds the paper one line
when it receives a carriage return (CR) control code. This signal is valid only in Epson LQ mode.
-INIT
-INIT from the system resets the printer to its initial power-on state. The BUSY line goes high, and any
received data are printed. When -INIT goes low, the printer resets itself to the power-on default state.
-ERROR
The printer sets the ERROR line low if it detects an error, such as an out-of-paper condition.
-SLCT IN
When this signal is high at initializing the printer, the DC1 and DC3 control codes are valid; otherwise,
they are invalid. This signal is valid only in Epson LQ mode.
Part 2: Printer
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