implement common_hal_busio_uart_clear_rx_buffer

hathach · hathach · commit 08cbb03bddfa · 2018-10-03T11:39:01.000+07:00
diff --git a/ports/nrf/common-hal/busio/UART.c b/ports/nrf/common-hal/busio/UART.c
@@ -250,7 +250,11 @@ uint32_t common_hal_busio_uart_rx_characters_available(busio_uart_obj_t *self) {
 }
 
 void common_hal_busio_uart_clear_rx_buffer(busio_uart_obj_t *self) {
-
+    // Discard received byte, and queue 1-byte transfer for rx_characters_available()
+    if ( self->rx_count > 0 ) {
+        self->rx_count = -1;
+        _VERIFY_ERR(nrfx_uarte_rx(&self->uarte, self->buffer, 1));
+    }
 }
 
 bool common_hal_busio_uart_ready_to_tx(busio_uart_obj_t *self) {

Original file line number	Diff line number	Diff line change
`@@ -250,7 +250,11 @@ uint32_t common_hal_busio_uart_rx_characters_available(busio_uart_obj_t *self) {`
`250`	`250`	`}`
`251`	`251`
`252`	`252`	`void common_hal_busio_uart_clear_rx_buffer(busio_uart_obj_t *self) {`
`253`		`-`
	`253`	`+ // Discard received byte, and queue 1-byte transfer for rx_characters_available()`
	`254`	`+ if ( self->rx_count > 0 ) {`
	`255`	`+ self->rx_count = -1;`
	`256`	`+ _VERIFY_ERR(nrfx_uarte_rx(&self->uarte, self->buffer, 1));`
	`257`	`+ }`
`254`	`258`	`}`
`255`	`259`
`256`	`260`	`bool common_hal_busio_uart_ready_to_tx(busio_uart_obj_t *self) {`