OctoClock firmware upgrade, added host driver

* OctoClock can communicate with UHD over Ethernet
* Can read NMEA strings from GPSDO and send to host
* Added multi_usrp_clock class for clock devices
* uhd::device can now filter to return only USRP devices or clock devices
* New OctoClock bootloader can accept firmware download over Ethernet
* Added octoclock_burn_eeprom,octoclock_firmware_burner utilities
* Added test_clock_synch example to show clock API

1 files changed, 49 insertions, 0 deletions

diff --git a/firmware/octoclock/lib/usart.c b/firmware/octoclock/lib/usart.c
new file mode 100644
index 000000000..3620ac5e9
--- /dev/null
+++ b/firmware/octoclock/lib/usart.c
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2014 Ettus Research LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <octoclock.h>
+#include <usart.h>
+
+#include <util/delay.h>
+#include <avr/io.h>
+
+void usart_init(void){
+    UCSR1B = (1 << TXEN) | (1 << RXEN) | (1 << RXCIE); //Turn on TX/RX circuitry, enable RX interrupts
+    UCSR1C = (3 << UCSZ0); //Use 8-bit character sizes, 1 stop bit, no parity
+    UBRR1H = (uint8_t)(BAUD_PRESCALE >> 8);
+    UBRR1L = (uint8_t)BAUD_PRESCALE;
+}
+
+char usart_getc(void){
+    while((UCSR1A & (1 << RXC)) == 0);
+
+    return UDR1;
+}
+
+char usart_getc_noblock(void){
+    return ((UCSR1A & (1 << RXC))) ? UDR1 : -1;
+}
+
+void usart_putc(char ch){
+    while((UCSR1A & (1 << UDRE1)) == 0);
+
+    UDR1 = ch;
+}
+
+void usart_putc_nowait(char ch){
+    if((UCSR1A & (1 << UDRE1)) != 0) UDR1 = ch;
+}