Anna Bridge
This example allows you to connect your debug terminal to some other serial-connected device on the system. You can then type AT commands at the terminal and get responses back for the serially connected device. Should work with something like an ESP8266 or similar connected in to the Arduino header.
Revision 0:0f1c0f6579ab, committed 2017-11-10
- Comitter:
- AnnaBridge
- Date:
- Fri Nov 10 16:08:43 2017 +0000
- Commit message:
- UARTSerial example 3
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/.gitignore Fri Nov 10 16:08:43 2017 +0000 @@ -0,0 +1,4 @@ +.build +.mbed +projectfiles +*.py*
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Fri Nov 10 16:08:43 2017 +0000
@@ -0,0 +1,50 @@
+#include "mbed.h"
+
+UARTSerial pc(USBTX, USBRX);
+UARTSerial device(MBED_CONF_APP_UART1_TX, MBED_CONF_APP_UART1_RX);
+
+static void copy_some(FileHandle *out, FileHandle *in) {
+ // To ensure performance, allow to read multiple bytes at once, although
+ // we don't expect to read many in practice.
+
+ // read() will return immediately, as we've already
+ // checked that `in` is ready with poll()
+ char buffer[32];
+ ssize_t read = in->read(buffer, sizeof buffer);
+ if (read <= 0) {
+ error("Input error");
+ }
+
+ // Then write them all out. Assuming output port is similar speed to input,
+ // this may block briefly, but not significantly.
+ ssize_t written = 0;
+ while (written < read) {
+ ssize_t w = out->write(buffer + written, read - written);
+ if (w <= 0) {
+ error("Output error");
+ }
+ written += w;
+ }
+}
+
+int main() {
+ char buffer[32];
+ pollfh fds[2];
+
+ fds[0].fh = &pc;
+ fds[0].events = POLLIN;
+ fds[1].fh = &device;
+ fds[1].events = POLLIN;
+
+ while (1) {
+ // Block until either of the 2 ports is readable (or has an error)
+ poll(fds, 2, -1);
+
+ if (fds[0].revents) {
+ copy_some(fds[1].fh, fds[0].fh);
+ }
+ if (fds[1].revents) {
+ copy_some(fds[0].fh, fds[1].fh);
+ }
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-os.lib Fri Nov 10 16:08:43 2017 +0000 @@ -0,0 +1,1 @@ +https://github.com/ARMmbed/mbed-os/#e62a1b9236b44e70ae3b0902dc538481c04d455b
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed_app.json Fri Nov 10 16:08:43 2017 +0000
@@ -0,0 +1,18 @@
+{
+ "config": {
+ "uart1_tx": {
+ "help": "UART1 TX pin",
+ "value": "NC"
+ },
+ "uart1_rx": {
+ "help": "UART1 RX pin",
+ "value": "NC"
+ }
+ },
+ "target_overrides": {
+ "K64F": {
+ "uart1_tx": "D1",
+ "uart1_rx": "D0"
+ }
+ }
+}