I/O Pin Initial Settings And Preventive Measures - Sony SS-HQ1 Application Notes

12.2.13.

I/O pin initial settings and preventive measures

CXD3172AR pins S0-S3 (pins 44, 46, 47, and 48) are parameter-controlled I/O pins (Bi-Directional pins). In
external synchronization mode, these pins are used for external synchronization input. However, during
initialization (XRST removed -> parameter application), they are force-set to output mode. Therefore, in order
to prevent short-circuiting during initialization, insert a resistor with approximately 10k ohm resistance.
CXD3172AR
If the pins are not being used as input pins (e.g., in INT mode), then they can be left open under the output
mode setting.
Table 12.2-31 CXD3172AR I/O pins and input mode settings
Pin Name Pin No
S0 44
S1 46
S2 47
S3 48
SG control
Fig 12.2-38 Measure to prevent shorting of CXD3172AR I/O pins
Setting Parameters
CAT1_Byte7,8
S0IN
S1IN
S2SEL
S3SEL
10k ohm
S0 (44pin)
S1 (46pin)
S2 (47pin)
S3 (48pin)
Initial Input
value setting
0 1
Controlled by SG
0 1
0 7 Output under other settings
0 7
224
- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005
External
INput
Remarks