Canon BJ-W3000 Service Manual page 61

CHAPTER 2. BASIC OPERATION
Data is transferred 8 bits at a time in the compatible mode. The data is transferred by hand-
shaking the STROBE, ACKNLG, and BUSY signals.
The computer sets 8 bits of data and outputs the STROBE signal to the printer. The printer
receives the data with the STROBE signal and responds by setting the BUSY signal to "H".
When data processing has been completed, the printer outputs the ACKNLG signal to notify
the computer that the data has been accepted. When data reception is possible, it sets the BUSY
signal to "L".
The Perror signal becomes "H" to indicate a warning or error in the printer.
The Select signal becomes "H" to indicate that the printer is in a printing mode (online, print-
ing, warning ON, etc.) and "L" when in a non-printing mode (offline, in pause, error ON, etc.)
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