From 53371d6a4924e72c0a8a843824e1bb78e42e81eb Mon Sep 17 00:00:00 2001
From: Tom Ball <tball@microsoft.com>
Date: Fri, 26 Jan 2024 16:23:25 -0800
Subject: [PATCH] disable NFC pins

---
 errors.txt          | 32 --------------------------------
 libs/core/codal.cpp | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 32 deletions(-)
 delete mode 100644 errors.txt

diff --git a/errors.txt b/errors.txt
deleted file mode 100644
index 4377269f1d2..00000000000
--- a/errors.txt
+++ /dev/null
@@ -1,32 +0,0 @@
- 85%] Building CXX object CMakeFiles/MICROBIT.dir/pxtapp/st7735/screen.cpp.obj
-/src/pxtapp/st7735/screen.cpp: In constructor 'pxt::WDisplay::WDisplay()':
-/src/pxtapp/st7735/screen.cpp:65:38: error: no matching function for call to 'codal::SPIScreenIO::SPIScreenIO(codal::SPI&)'
-             io = new SPIScreenIO(*spi);
-                                      ^
-In file included from /src/pxtapp/st7735/screen.cpp:9:0:
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:39:5: 
-note: candidate: codal::SPIScreenIO::SPIScreenIO(codal::NRF52SPI&)
-     SPIScreenIO(SPI &spi);
-     ^~~~~~~~~~~
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:39:5: note:   no known conversion for argument 1 from 'codal::SPI' to 'codal::NRF52SPI&'
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:35:7: note: candidate: constexpr codal::SPIScreenIO::SPIScreenIO(const codal::SPIScreenIO&)
- class SPIScreenIO : public ScreenIO
-       ^~~~~~~~~~~
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:35:7: note:   no known conversion for argument 1 from 'codal::SPI' to 'const codal::SPIScreenIO&'
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:35:7: note: 
-candidate: constexpr codal::SPIScreenIO::SPIScreenIO(codal::SPIScreenIO&&)
-/src/libraries/codal-core/./inc/drivers/SPIScreenIO.h:35:7: note:   
-no known conversion for argument 1 from 'codal::SPI' to 'codal::SPIScreenIO&&'
-/src/pxtapp/st7735/screen.cpp:84:86: error: invalid conversion from 'codal::SPI*' to 'codal::NRF52SPI*' [-fpermissive]
-
-             smart = new JDDisplay(spi, LOOKUP_PIN(DISPLAY_CS), LOOKUP_PIN(DISPLAY_DC));
-                                                                                      ^
-In file included from /src/pxtapp/st7735/screen.cpp:11:0:
-/src/pxtapp/st7735/jddisplay.h:52:5: note:   initializing argument 1 of 'pxt::JDDisplay::JDDisplay(codal::NRF52SPI*, codal::Pin*, codal::Pin*)'
-     JDDisplay(SPI *spi, Pin *cs, Pin *flow);
-     ^~~~~~~~~
-make[2]: *** [CMakeFiles/MICROBIT.dir/pxtapp/st7735/screen.cpp.obj] Error 1
-make[1]: *** [CMakeFiles/MICROBIT.dir/all] Error 2
-make: *** [all] Error 2
-
-
diff --git a/libs/core/codal.cpp b/libs/core/codal.cpp
index 70275c4b5ec..d75f434cdc8 100644
--- 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() {