PRELIMINARY DATA SHEET
MSP 34x5G
Micronas
37
3.4. Programming Tips
This section describes the preferred method for initial-
izing the MSP 34x5G. The initialization is grouped into
four sections:
–
SCART Signal Path (analog signal path)
–
Demodulator
–
SCART and I
2
S Inputs
–
Output Channels
See Fig. 2
–
1 on page 8 for a complete signal flow.
SCART Signal Path
1. Select analog input for the SCART baseband pro-
cessing (SCART DSP Input Select) by means of the
ACB register.
2. Select the source for each analog SCART output
(SCART Output Select) by means of the ACB regis-
ter.
Demodulator
For a complete setup of the TV sound processing from
analog IF input to the source selection, the following
steps must be performed:
1. Set MODUS register to the preferred mode and
Sound IF input.
2. Set preferred prescale (FM and NICAM) values.
3. Write STANDARD SELECT register.
4. If Automatic Sound Select is not active:
Choose FM matrix repeatedly according to the
sound mode indicated in the STATUS register.
SCART and I
2
S Inputs
1. Set preferred prescale for SCART.
2. Set preferred prescale for I
2
S inputs
(set to 0 dB after RESET).
Output Channels
1. Select the source channel and matrix for each out-
put channel.
2. Set audio baseband processing.
3. Select volume for each output channel.
3.5. Examples of Minimum Initialization Codes
Initialization of the MSP 34x5G according to these list-
ings reproduces sound of the selected standard on the
loudspeaker output. All numbers are hexadecimal. The
examples have the following structure:
1. Perform an I
2
C controlled reset of the IC.
2. Write MODUS register
(with Automatic Sound Select).
3. Set Source Selection for loudspeaker channel
(with matrix set to STEREO).
4. Set Prescale
(FM and/or NICAM and dummy FM matrix).
5. Write STANDARD SELECT register.
6. Set Volume loudspeaker channel to 0 dB.
3.5.1. B/G-FM (A2 or NICAM)
<80 00 80 00>
<80 00 00 00>
<80 10 00 30 20 03>
<80 12 00 08 03 20>
<80 12 00 0E 24 03>
// Softreset
// MODUS-Register: Automatic = on
// Source Sel. = (St or A) & Ch. Matr. = St
// FM/AM-Prescale = 24
,
FM-Matrix = MONO/SOUNDA
// NICAM-Prescale =
5A
hex
// Standard Select: A2 B/G or NICAM B/G
<80 12 00 10 5A 00>
<80 10 00 20 00 03>
or
<80 10 00 20 00 08>
<80 12 00 00 73 00>
// Loudspeaker Volume 0 dB
3.5.2. BTSC-Stereo
<80 00 80 00>
<80 00 00 00>
<80 10 00 30 20 03>
<80 12 00 08 03 20>
<80 12 00 0E 24 03>
// Softreset
// MODUS-Register: Automatic = on
// Source Sel. = (St or A) & Ch. Matr. = St
// FM/AM-Prescale = 24
,
FM-Matrix = Sound A Mono
// Standard Select: BTSC-STEREO
// Loudspeaker Volume 0 dB
<80 10 00 20 00 20>
<80 12 00 00 73 00>
3.5.3. BTSC-SAP with SAP at Loudspeaker Channel
<80 00 80 00>
<80 00 00 00>
<80 10 00 30 20 03>
<80 12 00 08 03 20>
<80 12 00 0E 24 03>
// Softreset
// MODUS-Register: Automatic = on
// Source Sel. = (St or A) & Ch. Matr. = St
// FM/AM-Prescale = 24
,
FM-Matrix = Sound A Mono
// Standard Select: BTSC-SAP
// Loudspeaker Volume 0 dB
<80 10 00 20 00 21>
<80 12 00 00 73 00>