- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005
200
System Switching Parameters
With the “ECK-28MHz INT / ECK-27MHz LL Switching System (automatic/manual setting system)”, the
CXD3172AR’s operation mode (MODESEL) must also be switched to match the input ECK frequency.
In addition, with the “ECK-28MHz INT / ECK-27MHz LL Switching System (automatic/manual setting system)”,
auto mode cannot be used. Therefore, because external synchronization mode is switched in SGMODE,
SGMODE must also be switched to match the INT/LL switch setting.
This function provides parameters for detecting the switching flag when ECK-28MHz INT and ECK-27MHz LL
switch, and simultaneously switching the MODESEL and SGMODE values based on the detection results.
presents an explanation of the parameters based on the numbers in the flow chart.
Fig 12.2-11 System Switching Control Flow
*1. SYSSELON
SYSSELON is a parameter for turning system switching control ON/OFF.
Table 12.2-16 SYSSELON Parameter
Parameter
Description
SYSSELON CAT12_Byte13_bit1
0[h]: System configuration switching function OFF
1[h]: System configuration switching function ON
*2. When SYSSELON is set to OFF (SYSSELON=0[h]), the MODESEL and SGMODE values do not switch.
The values originally set for SGMODE and MODESEL are applied.
Table 12.2-17 Parameters Subject to System Switching Control
Parameter
Description
MODESEL
CAT12_Byte1_bit0-3
DSP operation mode setting parameter
SGMODE
CAT17_Byte17_bit0-3
External synchronization mode setting parameter
START
SYSSELON
1[h] or 0[h]
SYSSELFLG
1[h] or 0[h]
1[h]
0[h]
1[h]
0[h]
・
MODESEL/SGMODE control flow
MODESEL MODESEL
SGMODE SGMODE
*1
*2
*3
*4
*4
MODESEL0 MODESEL
SGMODE0 SGMODE
MODESEL1 MODESEL
SGMODE1 SGMODE