This is an example of how to setup mbed to run on the ANNA-B112 using the EVK-NINA-B1 target for compilation

Revision:
0:67a616264a3f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Feb 27 21:02:19 2020 +0000
@@ -0,0 +1,51 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 20 Point Labs, LLC.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "mbed.h"
+#include "ANNA-B112.h"
+#include "platform/mbed_thread.h"
+
+// Blinking rate in milliseconds
+#define BLINKING_RATE_MS    500
+
+
+DigitalOut led(LED_B);
+UARTSerial radio(TX_PIN, RX_PIN, 115200);
+
+static Thread echoThread( osPriorityNormal, OS_STACK_SIZE / 2, NULL, "echo_thread" );
+void echoTask()
+{
+    while(true){
+        uint8_t inbuf[64];
+        int size;
+        if(radio.readable()){
+            size = radio.read(inbuf,sizeof(inbuf));  
+            radio.write(inbuf,size);
+        }
+    }
+}
+
+static Thread blinkThread( osPriorityNormal, OS_STACK_SIZE / 2, NULL, "pc_thread" );
+void blinkTask()
+{
+    while (true) {
+        led = !led;
+        thread_sleep_for(BLINKING_RATE_MS);
+    }  
+}
+
+int main()
+{
+    // Initialise the digital pin state
+    led = 1;
+    
+    // Start the threads
+    echoThread.start(echoTask);
+    blinkThread.start(blinkTask);
+
+    while (true) {
+        thread_sleep_for(1000); // Just get out of the way
+    }
+}