ZyXEL Elite 2864 User Guide - Page 39

AA Auto Answer indicator; lights up when the modem is in auto answer mode; flashes when modem rings. CD Carrier Detect indicator; lights up when a valid carrier is detected present on the line. TXD Transmit Data indicator; lights up when your DTE/computer trans- mits data to the modem. RXD Receive Data indicator; lights up when your DTE/computer receives data from the modem. The following four indicators have different meanings depending on whether the modem is connected to a DTE (computer or terminal) through either of the parallel or serial interfaces (SP or PCP is ON, DTE mode) or whether the modem is connected to a printer through the parallel port interface (PRP is ON, printer mode). DTR DTE mode: Data Terminal Ready indicator; lights up when the DTE or computer indicates that it is ready for communication by raising the corresponding RS232 signal. POL Printer mode: Printer On Line indicator; indicates the status of the printer's "Select" (SLCT) signal. It lights up when the printer is se- lected and is available for data transfer. DSR DTE mode: Data Set Ready indicator; lights up when modem is ready for communication. PSL Printer mode: Printer SeLect signal; indicates the signal status of "-Select In" from modem to printer. It lights up when printer is ena- bled to input data. RTS DTE mode: Request To Send indicator; indicates the signal status of RS232 signal RTS from DTE. RTS is used for hardware flow control in asynchronous data transmission. PPE Printer mode: Printer Paper End indicator; lights up when the print- er is out of paper. It indicates the signal status of "PE" from the print- er. CTS DTE mode: Clear To Send indicator; lights up when modem can ac- cept data for transmission. It indicates the signal status of RS232 signal CTS. PER Printer mode: Printer ERror indicator; lights up when an error con- dition exists in the printer, e.g., out ot paper or not on-line. It indi- cates the signal status of "-Error" from the printer. 3-3