Inherit from Serial and use software buffers for TX and RX. This allows the UART peripherals to operate in a IRQ driven mode. Overrides most (but not all) stdio functions as Serial did
Dependents: buffered_serial_test BLE_Police_HRM evena_BLE_Police_HRM df-2014-workshop-rfid-case-generator-k64f ... more
Example
#include "mbed.h"
#include "BufferedSerial.h"
BufferedSerial pc(USBTX, USBRX);
int main()
{
pc.baud(115200);
while(1)
{
Timer s;
s.start();
pc.printf("Hello World - buff\n");
int buffered_time = s.read_us();
wait(0.1f); // give time for the buffer to empty
s.reset();
printf("Hello World - poll\n");
int polled_time = s.read_us();
s.stop();
wait(0.1f); // give time for the buffer to empty
pc.printf("printf buffered took %d us\n", buffered_time);
pc.printf("printf polled took %d us\n", polled_time);
wait(0.5f);
}
}
Diff: BufferedSerial.cpp
- Revision:
- 13:c17c532bc4f8
- Parent:
- 11:779304f9c5d2
diff -r a0d37088b405 -r c17c532bc4f8 BufferedSerial.cpp
--- a/BufferedSerial.cpp Mon Mar 07 21:10:27 2016 +0000
+++ b/BufferedSerial.cpp Wed Feb 20 01:29:28 2019 +0000
@@ -26,7 +26,7 @@
BufferedSerial::BufferedSerial(PinName tx, PinName rx, uint32_t buf_size, uint32_t tx_multiple, const char* name)
: RawSerial(tx, rx) , _rxbuf(buf_size), _txbuf((uint32_t)(tx_multiple*buf_size))
{
- RawSerial::attach(this, &BufferedSerial::rxIrq, Serial::RxIrq);
+ RawSerial::attach(callback(this, &BufferedSerial::rxIrq), Serial::RxIrq);
this->_buf_size = buf_size;
this->_tx_multiple = tx_multiple;
return;
@@ -149,7 +149,7 @@
if(serial_writable(&_serial)) {
RawSerial::attach(NULL, RawSerial::TxIrq); // make sure not to cause contention in the irq
BufferedSerial::txIrq(); // only write to hardware in one place
- RawSerial::attach(this, &BufferedSerial::txIrq, RawSerial::TxIrq);
+ RawSerial::attach(callback(this, &BufferedSerial::txIrq), RawSerial::TxIrq);
}
return;
Sam Grove

