DSP signal acquisition general input/output GPIO test

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DSP signal acquisition general input/output GPIO test [Copy link]

GPIO is a general input/output port. Its direction can be set through the I/O direction register IODIR, and the level on the pin is reflected by the I/O data register IODATA. CPU and DMA controller can access these two registers in the I/O space. GPIO testing is divided into input port testing and output port testing. 1. Input port testing The steps of input port testing are as follows: (1) Set a pin as input direction through the I/O direction register IODIR; (2) Apply LVTTL signal to the pin that has been set as input direction; (3) DSP accesses the I/O data register IODATA, checks the logic level on the pin, and compares it with the applied LVTTL level to detect whether the input port is working properly. 2. Output port test The steps of output port test are as follows: (1) Set a pin as output direction through the I/O direction register IODIR; (2) Set the logic level of this pin in the I/O data register IODATA; (3) Measure the level of the pin and compare it with the set logic level to detect whether the output port is working normally.