COMSPHERE 3550 Series Data Service Units5-6 July 1999 3550-A2-GB20-40Table 5-1(1 of 2)DSU Configuration OptionsRate(Kbps): 9.6Next 64L 56 38.4 19.2 9.6 4.8 2.4 PrevDSU Rate. Sets the data rate (in kbps) of the DSU, which must be set to match the speed of the digital (DDS) circuit.64L — Select for 64 kbps LADS operation.56 to — Set to match the speed of the DDS circuit.2.4 kbpsNOTE: Both the control and tributary DSUs must be set to the same value.PrtSp(Kbps): 9.6Next 64 56 48 19.2 9.6 4.8 2.4 1.2 Disab PrevPort Speed (not displayed with a TDM/Flex installed). Sets the speed of the DTE port interface. The port speed is set toany valueless than orequal to the DSU Rate(Kbps) set above. The DSU performs rate adaption if the port speed is settoless than the DDS rate.64 to — Select the DTE’s port speed.1.2 kbpsDisab — Disables PrtSp(Kbps).TxClkSource: DDSNext Int Ext Prt1 Prt2 DDS PrevTransmit Clock Source. Specifies the transmit timing source for the DSU.Int — Select internal clock source to take timing from the DSU.Ext — Select external clock source when timing is taken from the external Transmit Timing lead on Port 1 only(not displayed if a TDM/Flex is installed).Prt1 or — Select the port that timing is to be taken from, using the selected port’s external TransmitPrt2 Timing lead(Prt2 is only displayed if a TDM/Flex is installed and enabled).DDS — Select the DDS network when the DSU is connected to a DDS network and the network provides thetiming, or when a LADS configuration with a remote DSU is providing the timing.Msg Clamp: EnabNext Enab Disab PrevMessage Clamping (only displayed when Full Mode is enabled). Controls data lead behavior when disruptive diagnostictests and commands are received from the remote DSU. It applies to both the DSU and DBM.Enab — Select to prevent diagnostic messages from reaching the DTE interface.Disab — Select if the remote DSU is configured for switched RTS; that is, RTS Control is set to DTE in the General(Gen) configuration options.TxElasStor: DisabNext Enab Disab PrevTransmit Elastic Store (only displayed when Full Mode is enabled and a TDM/Flex is not installed). Using a transmitbuffer on the DSU’s transmitted data (TXD) lead, serial data is clocked into the DSU’s elastic store using clock providedby the extended circuit received clock lead. The DSU’s own system timing is used to clock data out of the buffer.Transmit Elastic Store is reset each time the unit powers-up, the buffer overflows, or after the RTS lead makes anOff-to-ON transition.Enab — Select enable when interfacing with a DCE that receives clock from its own network source (e.g., a T1MUX or DSU that is on the DDS network).Disab — Select disable if you do not have an extended network or are providing the clock source to the extendednetwork (e.g., LADS with external clock).