Tait TM8100 Protocol Manual

Also see for TM8200 mobiles: Service manual Installation guide Installation guide Accessories manual Operator's manual

Contents

Tait TM8100 Protocol Manual Manual pdf 18 page image

18 CCDI TM8100/TM8200 Computer-Controlled Data Interface (CCDI) Protocol Manual© Tait Electronics Limited April 2007THSD TransmissionFormat For more information, refer to Technical Note TN-855-AN TM8000 andTB7100 Data Modem Facilities.Effective Over-AirData Rate The effective over-the-air data rate is lower than the set data rate.For more information, refer to Technical Note TN-855-AN TM8000 andTB7100 Data Modem Facilities.Lead-In Delay The lead-in delay begins after the transmitter key-up time. It gives thereceiver(s) at the other end time to open before data is sent.When data is detected at the radio’s input buffer, the following occurs:■ The transmitter keys up.■ A carrier is sent from the transmitter. When the carrier reaches its fullpotential, the lead-in delay begins.■ If the receiving base station is set to Repeater mode, the carrier isdetected and Rx Gate becomes active (opens), which in turn makes thePTT line active.■ The active PTT line keys up the transmitter.This sequence is repeated with as many base stations as are in the chain.The optimum length of the lead-in delay should be set keeping in mind thenumber of base stations that need to be activated before any data is sent.The lead-in delay must also allow for subaudible signalling decoding, if it isenabled, when used in conjunction with FFSK data.1.8 Command ModeCommand mode uses the Tait proprietary Computer Controlled DataInterface (CCDI), a command protocol embedded in the radio firmware.It is accessed using the serial port lines from the PC. In this mode, the baudrate between the computer equipment (DTE) and the radio (DCE) can beset to either 1200, 2400, 4800, 9600, 14400, 19200, 28800 or 115200(TM82000 only) baud using the programming applicationTxkey-uptimeLead InDelay dataLead OutDelay Txkey-downTx