Microcom 438TC, Operator'S Manual

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438TC Operator’s Manual - 880050-0100 13-25
RTS (Request To Send) - A status signal from the host PC (DTE) to the printer (DCE)
indicating when the PC has data to send to the printer. The printer (DCE) will only transmit
data to the PC (DTE) when it sees RTS up. RTS comes into the printer on pin #7 of the RS-
232 connector.
RXD (Receive Data) - An essential signal that carries data from the printer (DCE) to the
host PC (DTE) for 2-way RS-232 serial communication. Signal is also known as RX and
RD. RXD leaves the printer on pin #2 of the RS-232 connector.
SDRAM (Synchronous Dynamic Random Access Memory) – High density random
access memory that is commonly used to store application code. The 324M & 424M
printers do NOT use this type of memory.
SRAM (Static Random Access Memory)
– High speed random access memory that is
used to store label formats, graphics, and fonts temporarily. The slice buffer and serial
buffer (10Kbyte) are also in SRAM. This is volatile memory, which means that the
information is lost when the printer powers down. The 428M printers use a 512Kbyte SRAM
configured as 256K x 16.
Tag stock - Media that typically has no adhesive backing, thicker in nature, and generally is
a fanfold type media.
Thermal print head - A print head that uses thermal technology, to heat individual elements
or dots to produce images. Also referred to as print head in this manual.
TXD (Transmit Data) - An essential signal that carries data from the host PC (DTE) to the
printer (DCE) for 2-way RS-232 serial communication. Also known as TX and TD. This
signal comes into the printer on pin #3 of the RS-232 connector.
USB (Universal Serial Bus) - A high-speed asynchronous serial interface that connects a
PC to a peripheral, such as a printer. There are 3 versions of USB:
1) USB 1.0 transfers at 1M bits/second. (Hardly used at all anymore).
2) USB 1.1 transfers at 12M bits/second. (The 324 & 424 printers use this).
3) USB 2.0 transfers at 480M bits/second. (All newer PC’s use this).