AN2274 Freescale Semiconductor / Motorola, AN2274 Datasheet - Page 19

• Manufacturer Part Number: AN2274
• Description: Generic Tone Generation on the StarCore SC140 Core
• Manufacturer: Freescale Semiconductor / Motorola

3.5 Performance Measurements
The proposed tone generation module typically requires less than 0.1 MCPS. The worst case would be to change
the component every millisecond, but this mode of operation is not used in practice (typical component change
intervals are greater than 40 ms).
To provide a generator with generic properties and readable C Code, the tone generation program is composed of a
large number of tests and control instructions that increase memory usage. If the code is made more specific, that
is, dedicated to a specific case such as DTMF generation, the memory usage can be reduced significantly [8].
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Freescale Semiconductor
References
ITU-T Recommendation E.180/Q.35, Technical characteristics of tones for the telephone service.
MSC8101 Application Development System User’s Manual, Freescale Semiconductor, Inc.
A. V. Oppenheim, R. W. Schafer, J. R. Buck. Discrete Time Signal Processing. Prentice Hall, Second
edition, 1999.
ITU-T Recommendation G.711, Pulse Code Modulation (PCM) of Voice Signals, 1993.
Freescale Semiconductor, ADS File Server via Ethernet for MSC8101.
ITU-T Recommendation Q.24, Multi-frequency push bottom signal reception, 11/98.
ITU-T Recommendation Q.454, The Sending Part of the Multi-Frequency Signalling Equipment.
DTMF Transmitter/Receiver for MSC810x DSPs, Freescale Semiconductor.
DTMF
Germany Dial Tone
Japan Waiting Tone
Data / Channel
(Bytes)
168
Tone
Generic Tone Generation on the StarCore™ SC140/SC1400 Cores, Rev. 1
Table Size (Bytes)
142
Table 5. Typical MCPS Values
Table 6. Memory Usage
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805
820
820
Stack Size (Bytes)
C
’pyr†
24
Generation (MCPS)
Program Size (Bytes)
0.045
0.056
0.034
1906
References
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