Fortec Star CM1-BT1, Manual

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Module Description 37
CMx-BTx
3.16 User GPIO Interface
The CMx-BTx offers eight user-accessible GPIOs. These IOs are generated by a PCA9535 I²C
port expander and delivered through the connector (O) on the bottom-side of the module. These
IOs are able to signal an interrupt to the SoC. The bus address of the PCA9535 is found at
0x40.
For interface flexibility, these IOs run at 3.3V but are 5.0V tolerant (default.) By changing the sol-
der jumpers at R317/R318, the IO voltage can be changed to 5.0V permanently.
The GPIO interface supports a Hirose DF13-10 connector, and the following table defines the
GPIO signals.
Table 3-18: GPIO Signal Definitions (CN21)
Pin Signal Connector
1 GPIO0
2 GPIO1
3 GPIO2
4 GPIO3
5 GPIO4
6 GPIO5
7 GPIO6
8 GPIO7
9 VCC_GPIO (5.0 V default)
10 GND