Hello,

i am trying to learn to setup GPIF2. I have created a GPIF2 design with the following properties:

- Master / Synchronous / Internal / 8 Bit Bus / no multiplexing / 1 input / 1 output / 2 DMA flag lines

- I have a state machine with 3 states:

-- Start state

-- STATE0: Which should set OUTPUT0 to e.g. 0

-- STATE1: Which should set OUTPUT0 to e.g. 1

Then i have 2 transitions: from STATE0 to STATE1 when INPUT0 is set and back when INPUT0 is reset (polarity does not matter at the moment).

I have attached screen shots of my design and state machine to this posting.

A) I expect that when i toggle INPUT0, then i see some reaction on OUTPUT0, but OUTPUT0 always remains 0.

B) I also expect that GPIO16 (CLK) is an output, but value is Z.

C) GPIO[0...7] is also Z, but perhaps this is correct?

D) GPIO[8...15] is 0, perhaps correct, because no used (more assumed it is Z)?

E) I also tried first without a state machine at all, changing "initial value" between high and low (of course re-compling and re-flashing), but no reaction. Therefore i am not sure, if i control the state machine at all?

This i my code to load and start GPIF (i get no error output, especially from these function, but of course other debug output):

    CyU3PPibClock_t pibClock;

    /* Initialize the p-port block. */
    pibClock.clkDiv = 2;
    pibClock.clkSrc = CY_U3P_SYS_CLK;
    pibClock.isHalfDiv = CyFalse;
    /* Disable DLL for sync GPIF */
    pibClock.isDllEnable = CyFalse;
    apiRetStatus = CyU3PPibInit(CyTrue, &pibClock);
    if (apiRetStatus != CY_U3P_SUCCESS)
    {
        CyU3PDebugPrint (4, "P-port Initialization failed, Error Code = %d\n",apiRetStatus);
        CyFxAppErrorHandler(apiRetStatus);
    }

    /* Load the GPIF configuration for Slave FIFO sync mode. */
    apiRetStatus = CyU3PGpifLoad (&CyFxGpifConfig);
    if (apiRetStatus != CY_U3P_SUCCESS)
    {
        CyU3PDebugPrint (4, "CyU3PGpifLoad failed, Error Code = %d\n",apiRetStatus);
        CyFxAppErrorHandler(apiRetStatus);
    }

    /* Start the state machine. */
    apiRetStatus = CyU3PGpifSMStart (START, ALPHA_START);
    if (apiRetStatus != CY_U3P_SUCCESS)
    {
        CyU3PDebugPrint (4, "CyU3PGpifSMStart failed, Error Code = %d\n",apiRetStatus);
        if(apiRetStatus == CY_U3P_ERROR_NOT_CONFIGURED) CyU3PDebugPrint (4, "-> CY_U3P_ERROR_NOT_CONFIGURED)\n");
        if(apiRetStatus == CY_U3P_ERROR_ALREADY_STARTED) CyU3PDebugPrint (4, "-> CY_U3P_ERROR_ALREADY_STARTED)\n");
        CyFxAppErrorHandler(apiRetStatus);
    }

Have i missed something to enable GPIF? There is "isDQ32Bit", what value must it get when using 8 bit?

I have it on CyFalse, because i have not 32 bit interface.

Here now the state machine diagram:

Another question regarding DR_GPIO: How i can set OUTPUT to a certain value?

Toggle just switches the value?

Assert, ok, but how to set to 0, how to set to 1. The initial state has only one value, how to reach the other.

Or does it mean: initial state x -> assert gives initial state (x) / toggle gives inverted initial state (!x) ?