I am new to the nRF9160dk board. I have been able to compile and run some of the sample programs. I am now looking to have a simple program to talk to external uarts 0 and 1. I have found a githib project https://github.com/Rallare/fw-nrfconnect-nrf/tree/nrf9160_samples that has a simple UART example. I can build and load it but I am not sure where to configure the UART and how to get it to work.
I see the following for Uart0 in the device tree. so I am assuming this is where the baud rate and external pins are defined.
however when I run the program I do not get an indication that characters are seen on gpio_0 P28 which is on connector P27. I am using TeraTerm to connect.
I am assuming the TX/RX are relative to the nRF9160 board. in other words RX pin (28) is where it is expecting to see characters at 115200 baud.
I am assuming I do not need to connect to RTS/CTS.
I am sure it is something simple I left out or I am not doing. any help would be appreciated.
I am trying to build a simple application where I can type commands on a terminal emulator (putty, TeraTerm, etc.) and parse and execute those commands and send the output back to the terminal emulator. I have done this in the past on several other project and has proven to be quite effective in field support and debugging.
&uart0 {
status = "okay";
current-speed = <115200>;
tx-pin = <29>;
rx-pin = <28>;
rts-pin = <27>;
cts-pin = <26>;
};
the program is included below
/*
* Copyright (c) 2012-2014 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr.h>
//#include <misc/printk.h>
#include <sys/printk.h>
//#include <uart.h>
#include <drivers/uart.h>
static u8_t uart_buf[1024];
void uart_cb(struct device *x)
{
uart_irq_update(x);
int data_length = 0;
if (uart_irq_rx_ready(x))
{
data_length = uart_fifo_read(x, uart_buf, sizeof(uart_buf));
uart_buf[data_length] = 0;
}
printk("%s", uart_buf);
}
void main(void)
{
struct device *uart = device_get_binding("UART_0");
uart_irq_callback_set(uart, uart_cb);
uart_irq_rx_enable(uart);
printk("UART loopback start!\n");
while (1)
{
k_cpu_idle();
}
}
