Call Progress Tone Detection
by D2 Technologies, Inc.

Software Overview

D2's Call Progress (CP) Tone Detection algorithm module detects the North America precise call 
progress tones under a broad range of network conditions.
Designed to the VP Open interface, the CP Tone Detection module easily integrates with other VP 
Open modules, runs in real-time concurrently with other VP Open modules, and handles any number of 
voice ports assigned to the DSP. Like all of D2's algorithm modules, CP Tone Detection consists of 
robust software that is rigorously tested.

Features and Benefits

•	Detects North America precise tones for dial, busy, audible ring, intercept, reorder, message 
wait, and recall dial
•	Superior talk-off performance
•	Programmable cadence
•	Accepts telephone band codec or linear data
•	Meets Bellcore precise tone detection specifications

Processor and System Specifications

•	Devices supported: TMS320C2xx, TMS320C3x, TMS320C5x
•	Processor resource required:
•	Algorithm category: Telecommunications
TMS320C2xx (Est.)
TMS320C3x (Est.)
TMS320C5x
Program memory
1.6 kwords
1.1 kwords
1.41 kwords
Data memory/port
181 words
130 words
181 words
Processor loading worst case
1.3 MIPS
0.8 MIPS
1.1 MIPS

Usage Limitations or Performance Considerations

The host, voice data input and output, memory allocation, and module to module communication 
interfaces must conform to VP Open as described in the VP Open Software Interface Specification.

Algorithm Verification

D2's Call Progress Tone Detection algorithm module is validated through the following suite of 
tests:
•	D2 CP tone detection test for frequency deviation, twist, dynamic range and SNR
•	D2 CP tone talk-off test with Bellcore voice tapes
•	D2 CP tone talk-down test with echo canceller and the Bellcore voice tapes
•	VP Open interface validation – the CP Tone Detection module is integrated with other VP Open 
modules and tested concurrently in real-time on the D2 VDS50 system for multiple voice ports

Availability

Currently available for the TMS320C5x. A demonstration package is currently available for the TI 
EVM50 DSP board. Implementations for the TMS320C2xx and the TMS320C3x will be available 2Q 1996.

Company Background and Contact Information

D2 Technologies, Inc. was founded by David Y. Wong and David M. Lindsay to help companies innovate 
telecommunications and information products with voice processing technology, which include 
telephony and voice algorithms, real-time system software, and development services.
With over 20 years of experience in voice processing algorithms, real-time DSP implementation, 
real-time systems, telephone systems, and voice processing applications, D2's business model is to 
develop close partnerships with its customers via high levels of service and special engineering to 
ensure mutual success.
Contact:	D2 Technologies, Inc.
		Attn:  Product Sales
		104 West Anapamu Street, Suite J
		Santa Barbara,  CA 93101
		(805) 564-3424
		Fax:  (805) 966-2144
		e-mail:  sales@d2tech.com