Printer User Manual

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e XON/XOFF (DC1/DC3) Protocol + READY/BUSY (DTR) Protocol
z When initialized after the power is turned on, this printer becomes ready to receive data and
turns the DTR signal to the “High” level (READY). The printer also sends an XON code
(11H).
z When the blank positions in the receive buffer are 800 bytes or less, the printer turns the
DTR signal to the “Low” level (BUSY) and sends an XOFF code (13H).
z When the blank positions in the receive buffer are 2K bytes or more, the printer turns the
DTR signal to the “High” level (READY) and sends an XON code (11H).
z When there are no blank positions in the receive buffer, the printer discards data received
exceeding 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.)
z The printer sends an XOFF code (13H) when the power is off.
z The RTS signal is always “High”.
f RTS Protocol
z When initialized after the power is turned on, the printer turns the RTS signal to “High”
(READY).
z The printer turns the RTS signal to “Low” (BUSY) when the blank positions in the receive
buffer are 800 bytes or less.
z The printer turns the RTS signal to “High” (READY) when the blank positions in the receive
buffer are 2K bytes or more.
z When there are no blank positions in the receive buffer, the printer discards data received
exceeding the receive buffer capacity, without storing it in the buffer. (After detecting the
BUSY signal, the host computer must stop transmission before the printer receive buffer
becomes full.)
z The DTR signal is always “High” (READY).