Data Communications Networking Devices - 4th Ed.pdf

436 _________________________________ WIDE AREA NETWORK TRANSMISSION EQUIPMENTTable 4.23 Enhanced AT command set Hayes V-series Smartmodem 2400)CommandDescription&C0&C1&D0&D1&D2Assume data carrier always presentTrack presence of data carrierIgnore DTR signalAssume command state when an on-to-off transition of DTR occursHang up and assume command state when an on-to-off transition of DTRoccursReset when an on-to-off transition of DTR occursReset when enter low power mode when DTR is lowNo guard tone550 Hz guard tone1800 Hz guard toneRJ-11/RJ-41S/RJ-45S telco jackRJ-12/RJ-13 telco jackDisable local ¯ow controlEnable RTS/CTS local ¯ow controlEnable XON/XOFF local ¯ow controlEnable transparent XON/XOFF local ¯ow controlAsynchronous mode&D3&D4&G0&G1&G2&J0&J1&K0&K3&K4&K5&M0&M1 Synchronous mode 1&M2 Synchronous mode 2&M3 Synchronous mode 3&R0 Track CTSaccording to RTS&R1 Ignore RTS; always assume presence of CTS&S0 Assume presence of DSR signal&S1 Track presence of DSR signal&T0 Terminate test in progress&T1 Initiate local analog loopback&T3 Initiate local digital loopback&T4 Grant request from remote modem for RDL&T5 Deny request from remote modem for RDL&T6 Initiate remote digital loopback&T7 Initiate remote digital loopback with self test&T8 Initiate local analog loopback with self test&W0 Save storable parameters of active con®guration as pro®le 0&W1 Save storable parameters of active con®guration as pro®le 1&X0 Modem provides transmit clock signal&X1 Data terminal provides transmit clock signal&X2 Receive carrier provides transmit clock signal&Y0 Specify stored user pro®le 0 as power-up con®guration&Y1 Specify stored user pro®le 1 as power-up con®guration&ZStore telephone numberusually a term used by vendors other than Hayes Microcomputer Products tode®ne the commands used by their products to access and control such features asMNP, V.42, V.42 bis, and proprietary methods of error control and data compression.Microcom has de®ned a series of AT command extensions to control andaccess error control, data compression, and ¯ow control. Used by the MicrocomAX series of modems, the extensions have been adopted by Intel, Okidata, PracticalPeripherals, Prometheus, and Ven-Tel. Modems manufactured by other vendors