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BJC-2000
BJC-2000
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.
ECP Mode
Host Clk [Input]
This signal handshakes with the PeriphAck signal when data is transferred form the
host computer to the printer. A Low Host Clk signal indicates that data has been
output along the data buses (Data1-8).
The signal goes High as a response to a High PeriphAck signal. It remains High
during reverse data transmission.
Data 1-8 [Input/Output]
This signal is an input signal when data is transferred from the host computer to
the printer. During reverse data transmission, this is an output signal and the
printer uses this data bus to send data to the host computer.
Periph Clk [Output]
When data is transferred from the printer to the host computer, this signal remains
High. Periph Clk signal is lowered during reverse transmission phase and indicates
that data has been sent to the host computer. This signal is also High in response
to the High HostAck signal from the host computer.
Periph Ack [Output]
Periph Ack signal goes Low when the printer is ready to receive data from the host
computer. Once the data is received the signal goes High. During the reverse data
transmission phase, this signal indicates whether the data sent from the printer to
the data bus was "command" or "data."
Low: "Command," High: "Data"
Ack Reverse [Output]
Ack Reverse signal remains High when data is transferred from the host computer
to the printer. During the reverse data transmission phase, the signal remains Low.
The Reverse Request signal from the host computer goes Low to request a switch
from the forward data transmission phase to the reverse data transmission phase.
In response to the Low Reverse Request signal, Ack Reverse signal goes low to
indicate that the request was accepted.
When the Reverse Request signal from the host computer goes High to request a
switch from the reverse data transmission phase to forward data transmission
phase, Ack Reverse signal goes High to indicate the switch over request has been
accepted.
X flag [Output]
This signal remains High in ECP mode.
Host Ack [Input]
This signal indicates the nature of the signal along the data bus when data is
transferred from the host computer to the printer. A Low Host Ack indicates
"command" whereas a High Host Ack indicates "data."
During reverse data transmission, this signal handshakes with the Periph Clk
signal. When the host computer is ready to accept data from the printer, this signal
goes Low. After data is received the signal goes High.
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Part 2: Product Specifications
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