Digital Voice Systems VC-20-ATC-10B Especificaciones descargar pdf (Pagina 88)

FAA20 Embedded NEXCOM Vocoder

Board Manual

This manual has been prepared for the Federal Aviation Administration.

FA100-00107 (March 2004) – Rev 1.0.0 Page 82

8.3.17 FRAMESIZE

The FRAMESIZE command sets/gets the PCM and NIB frame sizes used

when internal interface timing is enabled. Two different rates can be

assigned for each interface: one for normal timing mode and one for

truncated timing mode.

Table 28: FRAMESIZE Command Syntax

ATTRIBUTE DESCRIPTION

SYNTAX FRAMESIZE [interface [tmode [rate]]]

interface PCM Selects the PCM interface

NIB Selects the NIB interface

tmode NORM Selects normal timing mode

TRUN Selects truncated timing mode

PAR AMETERS

size Desired frame size entered as a positive decimal clock

count. The maximum PCM frame size is 4096.

FLASH YES

Print current frame size settings (default settings shown).

COM1: framesize

> FRAMESIZE PCM NORM = 480

> FRAMESIZE PCM TRUN = 480

> FRAMESIZE NIB NORM = 192

> FRAMESIZE NIB TRUN = 230

Change NIB framesize setting.

COM1: clkrate nib trun 192

> FRAMESIZE NIB TRUN = 192

EXAMPLES

Print NIB frame sizes

COM1: clkrate nib

> FRAMESIZE NIB NORM = 192

> FRAMESIZE NIB TRUN = 192

Note: Do not enter any leading ‘0x’ characters.

The FAA20 uses the processor’s Multi-channel Buffered Serial Ports

(MCBSPs) to generate interface timing; therefore, frame sizes are limited to

values that can be generated using the processor execution clock and a

fixed number of dividers. Note: When external timing is provided, these

limitations do not apply.

The FAA20 supports a special framing mode when the truncated nibble

frame size is set to 230 and the nibble clock source is set to internal (INT).

For more information on this mode, see Section 5.2.3.

1 2 ... 83 84 85 86 87 88 89 90 91 92 93 ... 108 109

Sin comentarios

Digital Voice Systems VC-20-ATC-10B Especificaciones Pagina 88