User`s manual

BD2-1220/1221 User’s Manual
14
6.2 Description of Input and Output signals
6.2.1 Input signals
• DATA 0~7: An 8-bit parallel signal. (Active “High”)
• nSTROBE: A strobe signal to help read 8-bit data. (Active “Low”)
• nRESET: Resets the control board (active “Low”).
6.2.2 Output signals
• nACK: An 8-bit data request signal, which is output at the end of a Busy signal.
(Active “Low”)
• BUSY: A signal to indicate a busy state of the control board. Input new data when this signal is
“Low”. (Active “High”)
• nFAULT: This signal becomes “Low” when alarmed. At this time, all control circuits in the control
board are deactivated. (Active “Low”)
• PE: A signal to indicate that the paper supply has become low or has run out completely.
(Active “High”)
6.2.3 Power related signal
• GND: Common ground on circuits.
6.3 Electrical Characteristics
(1) Input signal level
“High” level: 0.7Vdd MIN
“Low” level: 0.3Vdd MAX
(2) Output signal level
“High” level: Vdd-0.1V MIN
“Low” level: 0.1V MAX
(3) Input and output conditions
The nRESET and Data 0-7 inputs are pulled up to Vdd with 10 KΩ and 50 KΩ resistors, respectively. All
other input and output lines are pulled up to Vdd with 3.3 KΩ resistors.
Vdd
Vdd
Control Board Side
Resistor
Twisted Pair Wire
Twisted Pair Wire
Resistor
74HC14 or equivalent
74HC05 or equivalent
Host Side