Clean up test code

Separate/consolidate board initialization code, and a few functions
that are shared across tests. Update the Makefile accordingly.

Resolves #18

firmware/Test/Apps/clock.cpp

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2020  Max Regan
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "printf.h"
+
+#include "Bsp/Drivers/GpioDriver.h"
+#include "Bsp/Drivers/RtcDriver.h"
+#include "Bsp/Drivers/UsartDriver.h"
+#include "Bsp/LowPowerTaskScheduler.h"
+#include "Bsp/macros.h"
+
+#include "TestBoard.h"
+#include "test.h"
+
+using BSP::Time;
+using BSP::time_t;
+
+[[noreturn]] void main() {
+
+    board_init();
+
+    g_test_uart.tx_blocking(test_start_text);
+
+    BSP::time_t now;
+    now = Test::get_time();
+    BSP::time_t end = now + Time::seconds(10);
+
+    g_test_uart.tx_blocking("GO\r\n");
+    static char buffer[40] = { 0 };
+    while (now < end) {
+        snprintf(buffer, sizeof(buffer), "%lld\r\n", BSP::Time::to_micros(now));
+        g_test_uart.tx_blocking(buffer);
+        now = Test::get_time();
+    }
+    g_test_uart.tx_blocking("STOP\r\n");
+
+    g_test_uart.tx_blocking(test_pass_text);
+
+    TEST_SPIN();
+}