Software for Telecoms & Audio
V.25 Modem Function TMS320C5000 DSP Code
implements the ITU function V.25 for data modems. This is the 2100Hz auto-answer
sequence sent from the answering end at the start of a PSTN modem connection.
As well as audibly denoting a far-end modem in answer mode, the 2100Hz
signal automatically disables network echo suppressors and, if periodically
phase reversed as with the code here, also network echo cancellers.
Interfaces: at the sample interface, the code can operate at 8.0kHz and 9.6kHz sample rates. At the control interface, the assembler code has control word access to set V.25 segment durations, to sequence operation and to set operating parameters such as data size, and one diagnostic word to convey data transfer status such as V.25 progress. With the C wrapper, control and diagnostics are provided by routine call arguments and returned values.
- #figures are for TMS320C54x operation with the assembler interface
Availability: NOW - sale is under licence - integration support offered