We are using the standard UART debug facility.  However we have disabled the preample.

    CyU3PDebugPreamble(CyFalse);

Has anyone else seen this problem?

We are seeing this on 2 different boards, so we don't think it is hardware related.  Does anyone have any suggests as to why this might be failing.  We see different behavior just download the code to the board a few times, without any rebuilds or changes.

Oliver

 Hi Oliver,

Rephrasing your above post,

UART print doesn't seem to work right all the time. Garbled messages and partial messages are seen from time to time. If the preamble is disabled everything works fine. Is my understanding right?

Have you tried using it with a dedicated serial port rather than through a USB to serial converter? Just wanted to isolate the issue rather than having unknown variables in the equation.

Regards,

Anand

On my DevBoard the RTS and CTS connections were wrong. Maybe this also your problem.

-Silvio

We don't have any USB 3.0 computers with UARTs on them these days.  We have used 3 different brands of serial convertors, but they might all be based on variants of the FTDI chip.

Disabling the preamble seems to help (but that might be confirmation bias) but it certainly does not fix the problem.

We are setting up the UART with these options

    /* Set UART Configuration */

    uartConfig.baudRate = CY_U3P_UART_BAUDRATE_115200;

    uartConfig.stopBit = CY_U3P_UART_ONE_STOP_BIT;

    uartConfig.parity = CY_U3P_UART_NO_PARITY;

    uartConfig.txEnable = CyTrue;

    uartConfig.rxEnable = CyFalse;

    uartConfig.flowCtrl = CyFalse;

    uartConfig.isDma = CyTrue;

I am also using a USB to Serial converter and my symtoms where very similar to yours. Since RTS and CTS signals where connected wrong, the Host was driving against the FX3 board and the RS232 converter on the FX3 board got disturbed. It's easy enough to check: Just hook up a scope on the RTS and CTS lines.

-Silvio

Hi,

I experience same problem. With former versions of SDK, no problem I could see debug messages correctly.

I don't know if this is related to, but ARM GCC version was 4.4.1 and SDK was 466 to 540.

With newer version of SDK (630), it is impossible to see any debug message although debug string are present in the .img file. I have pined the input of the serial to usb converter : there is nothing sent from FX3 so this is not related to some problem with RTS/CTS.

I've tested the simplest examples from firmware example (such as GpioApp) that were perfectly working with former SDK versions but now it is not possible to get such a simple out as "hello world\n".

I'm working in 16 bits mode (exactly as in GpioApp example) and I'm waiting for a solution to solve this.

Best Regards.

Hi oliverks,

I saw the same issues (incomplete debug messages) and used the same workaround to add some sleeps before printing debug-messages. Seem to be a (maybe interrupt?) priority-issue of FX3's- hardware?!

Regards,
Rob