disable NFC pins

microsoft · Jan 27, 2024 · 53371d6 · 53371d6
1 parent d96f8c1
commit 53371d6
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Showing 2 changed files with 38 additions and 32 deletions.
diff --git a/errors.txt b/errors.txt
diff --git a/libs/core/codal.cpp b/libs/core/codal.cpp
@@ -49,11 +49,49 @@ MicroBit uBit;
 MicroBitEvent lastEvent;
 bool serialLoggingDisabled;
 
+#if defined(NRF52840) || defined(NRF52833)
+#define IS_3_3_V() ((NRF_UICR->REGOUT0 & 7) == 5)
+#else
+#define IS_3_3_V() 1
+#endif
+
+static void disableNFConPins() {
+    // Ensure NFC pins are configured as GPIO. If not, update the non-volatile UICR.
+    if (NRF_UICR->NFCPINS || !IS_3_3_V()) {
+        DMESG("RESET UICR\n");
+        // Enable Flash Writes
+        NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos);
+        while (NRF_NVMC->READY == NVMC_READY_READY_Busy)
+            ;
+
+        // Configure PINS for GPIO use.
+        if (NRF_UICR->NFCPINS)
+            NRF_UICR->NFCPINS = 0;
+
+#if defined(NRF52840) || defined(NRF52833)
+        // Set VDD to 3.3V
+        if ((NRF_UICR->REGOUT0 & 7) != 5)
+            NRF_UICR->REGOUT0 = (NRF_UICR->REGOUT0 & ~7) | 5;
+#endif
+
+        // Disable Flash Writes
+        NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos);
+        while (NRF_NVMC->READY == NVMC_READY_READY_Busy)
+            ;
+
+        // Reset, so the changes can take effect.
+        NVIC_SystemReset();
+    }
+}
+
 void platform_init() {
     microbit_seed_random();
     int seed = microbit_random(0x7fffffff);
     DMESG("random seed: %d", seed);
     seedRandom(seed);
+
+    // not working here, try in CODAL
+    // disableNFConPins();
 }
 
 void initMicrobitGC() {