Merge pull request #1 from thesupershan/lpc1768-us-ticker

choose which lpc1768 timer to use for us_ticker.c

Author: thesupershan

targets/TARGET_NXP/TARGET_LPC176X/us_ticker.c

@@ -28,8 +28,19 @@ const ticker_info_t* us_ticker_get_info()
 
 static bool us_ticker_inited = false;
 
+#if MBED_CONF_TARGET_US_TICKER_TIMER == 0
+#define US_TICKER_TIMER      ((LPC_TIM_TypeDef *)LPC_TIM0_BASE)
+#define US_TICKER_TIMER_IRQn TIMER0_IRQn
+#elif MBED_CONF_TARGET_US_TICKER_TIMER == 1
+#define US_TICKER_TIMER      ((LPC_TIM_TypeDef *)LPC_TIM1_BASE)
+#define US_TICKER_TIMER_IRQn TIMER1_IRQn
+#elif MBED_CONF_TARGET_US_TICKER_TIMER == 2
+#define US_TICKER_TIMER      ((LPC_TIM_TypeDef *)LPC_TIM2_BASE)
+#define US_TICKER_TIMER_IRQn TIMER2_IRQn
+#else
 #define US_TICKER_TIMER      ((LPC_TIM_TypeDef *)LPC_TIM3_BASE)
 #define US_TICKER_TIMER_IRQn TIMER3_IRQn
+#endif
 
 void us_ticker_init(void) {
     if (us_ticker_inited) {

targets/targets.json

@@ -247,6 +247,12 @@
         "release_versions": ["2", "5"],
         "device_name": "LPC1768",
         "bootloader_supported": true,
+        "config": {
+            "us-ticker-timer": {
+                "help": "Chooses which timer (0-3) to use for us_ticker.c",
+                "value": 3
+            }
+        },
         "overrides": {
             "network-default-interface-type": "ETHERNET"
         }