1. OUTLINE
1.5 ELECTRONICS SPECIFICATIONS
XON/XOFF (DC1/DC3) protocol + READY/BUSY (DTR) protocol
•When initialized after power on, this printer becomes ready to receive data and converts the DTR signal to "High" level (READY). The printer sends an XON code (11H).
•When the free area in the receive buffer are 10K bytes or less, the printer converts the DTR signal to "Low" level (BUSY) and sends an XOFF code (13H).
•When the free area in the receive buffer are 512KB or more, the printer converts the DTR signal to "High" level (READY) and sends an XON code (11H).
•When there is no free area in the receive buffer, the printer discards received data which exceeds the receive buffer capacity without storing it in the buffer. (After detecting the XOFF code or BUSY signal, the host computer must stop transmission before the printer receive buffer becomes full.)
•The printer sends an XOFF code (13H) at power off time.
•The RTS signal is always “High” level.
READY/BUSY (RTS) Protocol
•When initialized after power on, this printer becomes ready to receive data and converts the RTS signal to "High" level (READY).
•The printer converts the RTS signal to “Low” level (BUSY) when the free area in the receive buffer amount to 10K bytes or less.
•The printer converts the RTS signal to “High” level (READY) when the free area in the receive buffer amount to 512KB or more.
•When there is no free area in the receive buffer, the printer discards received data which exceed the receive buffer capacity without storing it in the buffer. (After detecting a BUSY signal, the host computer must stop transmission before the printer receive buffer becomes full.)
•The DTR signal is always “High” level (READY).
•The host should keep the DSR signal “High” level.
NOTE: Be sure to select the READY/BUSY (RTS) protocol when controlling the flow between the Windows. Also, be sure to select “Hardware” for the flow control in the Windows communication port setting.
kPin description
Pin No. | Signal | I/O | Description | |
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1 | FG (Frame Ground) | Ground line for circuit protection. | ||
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| Data line from which the printer receives data from the host | |
2 | RD (Received Data) | Input | (receive data line). | |
Logic “1” is “Low”, and “0” is “High”. It is LOW (MARK) while | ||||
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| no data is being sent. | |
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| Data line from which the printer sends data to the host (send | |
3 | TD (Transmit Data) | Output | data line). | |
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| Logic “1” is “low”, and “0” is “High”. It is LOW (MARK) while | |
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| no data is being sent. | |
4 | CTS (Clear to Send) | Input | Input signal from the host. This printer ignores this signal. | |
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| Output signal to the host. | |
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| When READ/BUSY (RTS) protocol is selected, | |
5 | RTS (Request to Send) | Output | this signal means READY to receive data. | |
When the receive buffer is nearly full, the signal turns to | ||||
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| “Low”, and “High” when nearly empty. | |
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| In case of other protocol is selected, this signal is always | |
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| “High” level after the power is turned on. | |
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| Output signal from the printer. | |
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| When READY/BUSY (DTR) or XON/XOFF | |
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| (DC1/DC3)+READY/BUSY (DTR) is selected, this signal | |
6 | DTR (Data Terminal Ready) | Output | means READY to receive data. | |
When the receive buffer is nearly full, the signal turns to | ||||
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| “Low”, and “High” when nearly eimpty. | |
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| In case of XON/XOFF (DC1/DC3) or READY/BUSY (RTS), | |
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| this signal is always “High” level after the power is turned on. | |
7 | SG (Signal Ground) | Ground line for all data and control signals. | ||
20 | DSR (Data Set Ready) | Input | Input signal from the host. It must be “High” for the printer to | |
receive data. | ||||
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