Canon Color Bubble Jet BJC-1000 Series, Руководство по обслуживанию

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Host Busy [Input]
• Reverse data transmission phase:
Indicates that the host computer is ready to receive the data from the printer by
making the Host Busy signal Low. After that, it goes High in synchronizing with
Low pulse of Ptr Clk signal to verify receiving data.
• Reverse idle phase:
The Host Busy signal goes High in response to the Low pulse of the Ptr Clk signal,
and enters the reverse data transmission phase again.
lNIT [Input]
When this signal becomes Low, the printer’s state becomes BUSY. When the signal
changes from Low to High, it resets the printer control system to the initial state.
This signal is normally High and the pulse width must be at least 0.5 µs at the
printer side.
After initializing, the printer enters the compatible mode.
DataAvail [Output]
• Reverse data transmission phase:
Indicates bit 0 and bit 4 of the transmission data.
• Negotiation phase:
Informs the host computer if there is reverse transmission data or not in
synchronizing with the falling edge of the Ack Data Req signal. “L” means that
there is reverse transmission data.
1284 Active [Input]
This signal confirms that the printer is a 1284 compatible device when 1284 Active
signal goes High and Host Busy signal goes Low. It goes Low with the termination
phase.
Part 2: Product Specifications BJC-1000
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