UART Implementation

RE: UART Implementation

Muzammil — Tue, 18 Sep 2018 01:50:44 GMT

Hi Jorgen,

I have tried a couple of methods to get the data back using app_uart_get() but unfortunately i am only getting is FF(form feed). Can you show me an example where we can simply get the data and print on the terminal(putty).

This is one of the way I have tried to get the data.

Here is the terminal output-

RE: UART Implementation

Jørgen Holmefjord — Wed, 29 Aug 2018 08:13:43 GMT

The UART Example in the SDK show how you can use app_uart_put/app_uart_get to transmitt and receive bytes.

RE: UART Implementation

Muzammil — Tue, 28 Aug 2018 23:48:53 GMT

Hi Jorgen,

I have managed to use the command -? and get a response back using a different UART response call but however according to the data sheet of LPC1519 in ISP commands when i am trying to send a "K" its just echoing me back with K. Can you give an example of how can i use app_uart_get() to get a response back of command K/J.

(k-read boot code version)

Here is where i am calling and getting a response back -

console_putc(63);
char ch;
for (int i = 0; i < 200; i++)
 {
    timer_util_msec_delay(30);
   // console_putc(63);
    if (ch) console_putc(ch);    
    ch = uGetc(CONSOLE_DEV);   
 }

for (int i = 0; i < 20; i++)
 {console_putc(75);
    timer_util_msec_delay(50);
   // console_putc(63);
    if (ch) console_putc(ch);    
    ch = uGetc(CONSOLE_DEV);   
 }

app_uart_flush();

Here is the response on putty-

RE: UART Implementation

Jørgen Holmefjord — Mon, 27 Aug 2018 13:58:21 GMT

I still don't understand what your error is. The line 'app_uart_put(*cmd) == "?";' does not make any sense. The function will return an error code, this will not correspond to "?". If you want to write "?" to the UART, you can use 'app_uart_put('?');'. If you expect a response, you need to call app_uart_get().

RE: UART Implementation

Muzammil — Sun, 26 Aug 2018 22:03:52 GMT

Hi Jorgen,

NXP LPC1519 has its own command which when asked replies whit the corresponding command, (Like when asked ? it replies back with synchronized).

So i am trying to ask NXP the commands via UART of NRF, which i am not successful at this stage. For my understanding and research I came across app_uart_put() , which is meant to put data on the UART TX pin and app_uart_get() , to get UART response on RX pin.

And sorry for - "app_uart_put(*cmd) == "?"; I had modified the code, So here is where i had defined it-

static void send_uart(char* cmd)
{
    while(app_uart_put(*cmd) == NRF_SUCCESS)
    {
     cmd++;
   }
    
}

void nxp_flashing(void)
{
 
    ret_code_t err_code;
    int* cmd;
   char rsp[5];
    uint8_t cr, i;
    uint8_t  ch;

        console_printf("NXP flashing\n");
        nrf_delay_ms(1000);

        nrf_gpio_pin_clear(NXP_BOOT_PIN_NUMBER);
        nrf_gpio_pin_clear(NXP_RESET_PIN_NUMBER);
        nrf_delay_ms(1000);
        nrf_gpio_pin_set(NXP_RESET_PIN_NUMBER);
        nrf_delay_ms(3000);
        nrf_gpio_pin_set(NXP_BOOT_PIN_NUMBER);
        nrf_delay_ms(3000);
 
        board_set_console_uart_baudrate(115200);
        
         app_uart_put(*cmd) == "?";     
         app_uart_flush(); 
 //      send_uart(cmd);
       
  //     console_printf(app_uart_get, "output: \n" );
   }

The internal connections are as below-

Is there any other way to ask NXP its commands via UART.

Thanks

RE: UART Implementation

Jørgen Holmefjord — Fri, 24 Aug 2018 08:11:38 GMT

Hi,

Can you provide some more details on what you mean by "most of the time its says error"?

What says error?
What is the error?
What is this line supposed to do: "app_uart_put(*cmd) == "?";"? Where is cmd set?

Best regards,
Jørgen