- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005
192
12.2.3.
Internal mode (INT)
In this mode, external synchronization is not applied.
There are two different system configurations: a 1-clock/digital encoder system, and an ECK master–MCK PLL
system. The SGMODE set value is 0[h] (see
1-clock/digital encoder system configuration
In this system, the DSP is operated using just one clock. The encoding clock (ECK) is supplied to also
generate the system driving clock inside the DSP.
Typically X’tal oscillation is used to generate the encoding clock (ECK).
shows the system block
diagram.
presents the external input signals.
Fig 12.2-1 Internal mode (1-clock/digital encoding)
Table 12.2-10 External input signals (1-clock/digital encoding)
Pin Name
Pin No
Input Signal
S0 44pin
EXVIDEOY 57pin
EXVIDEO
58pin
Connected to 3.3V
* In INT mode S0 (pin 44) is not controlled by SGMODE, so any I/O setting can be set. However, under the
CXD3172AR default values, S0 is set to input. Therefore, to set input, pull it up to 3.3V in accordance with
the system you are using.
CXD3172AR
42
43
88
87
86
ECK
(X'tal)
46
47
48
44
49
57
58
ES
CI
ES
CO
EC
K
PC
O
M
P
EXV
ID
EO
Y
EX
VID
E
O
S0
S1
S4
S3
S2
MCK
3.3V