added support for NFC wake

tag_fw/i2cdevices.c

@@ -23,6 +23,24 @@ extern void dump(uint8_t* __xdata a, uint16_t __xdata l);  // remove me when don
 extern uint8_t __xdata blockXferBuffer[];
 __xdata uint8_t i2cbuffer[18];
 
+bool supportsNFCWake() {
+    P1PULL |= (1 << 3);
+    timerDelay(33300);  // wait 25 ms
+    uint32_t pcount = 0;
+    P1PULL &= ~(1 << 3);
+    while (P1_3 && pcount < 10000) {
+        pcount++;
+    }
+    if (pcount < 10000) {
+        // P1_3 (Field Detect) dropped to 'low' pretty fast, this means the load on this pin is high
+        pr("This tag currently does not support NFC wake, load on the FD pin (P1.3) is pretty high.\nOn some boards, a pull-up resistor backpowers the NFC IC. Consider removing it!\n");
+        return false;
+    } else {
+        // No reason to believe this pin is currently loaded down severely
+        return true;
+    }
+}
+
 void loadRawNTag(uint16_t blocksize) {
     struct I2cTransaction __xdata i2ctrans;
     if (blocksize > 864) blocksize = 864;

tag_fw/i2cdevices.h

@@ -2,6 +2,7 @@
 #define _I2CDEV_H_
 #include <stdint.h>
 
+bool supportsNFCWake();
 void loadURLtoNTag();
 void loadRawNTag(uint16_t blocksize);
 bool i2cCheckDevice(uint8_t address);

tag_fw/main.c

@@ -23,8 +23,6 @@
 
 // #define DEBUG_MODE
 
-uint8_t __xdata capabilities = 0;
-
 void displayLoop() {
     powerUp(INIT_BASE | INIT_UART);
 
@@ -180,16 +178,22 @@ void main() {
         }
     }
 
-    pr("BOOTED>  %d.%d.%d%s", fwVersion / 100, (fwVersion % 100) / 10, (fwVersion % 10), fwVersionSuffix);
+    pr("BOOTED>  %d.%d.%d%s\n", fwVersion / 100, (fwVersion % 100) / 10, (fwVersion % 10), fwVersionSuffix);
 
 #ifdef HAS_BUTTON
     capabilities |= CAPABILITY_HAS_WAKE_BUTTON;
 #endif
     powerUp(INIT_I2C);
-    if (i2cCheckDevice(0x55)){
+    if (i2cCheckDevice(0x55)) {
+        powerDown(INIT_I2C);
         capabilities |= CAPABILITY_HAS_NFC;
+        if (supportsNFCWake()) {
+            pr("This board supports NFC wake!\n");
+            capabilities |= CAPABILITY_NFC_WAKE;
+        }
+    } else {
+        powerDown(INIT_I2C);
     }
-    powerDown(INIT_I2C);
 
     pr("MAC>%02X%02X", mSelfMac[0], mSelfMac[1]);
     pr("%02X%02X", mSelfMac[2], mSelfMac[3]);

tag_fw/powermgt.c

@@ -39,6 +39,8 @@ bool __xdata lowBattery = false;
 uint16_t __xdata longDataReqCounter = 0;
 uint16_t __xdata voltageCheckCounter = 0;
 
+uint8_t __xdata capabilities = 0;
+
 bool __xdata spiActive = false;
 bool __xdata uartActive = false;
 bool __xdata eepromActive = false;
@@ -130,7 +132,7 @@ static void configI2C(const bool setup) {
         P1FUNC |= (1 << 4) | (1 << 5);
         P1PULL |= (1 << 4) | (1 << 5);
         i2cInit();
-        i2cCheckDevice(0x50); // first transaction after init fails, this makes sure everything is ready for the first transaction
+        i2cCheckDevice(0x50);  // first transaction after init fails, this makes sure everything is ready for the first transaction
     } else {
         P1DIR |= (1 << 6);
         P1_6 = 0;
@@ -259,13 +261,23 @@ void doSleep(const uint32_t __xdata t) {
 
 #ifdef HAS_BUTTON
     // Button setup on TEST pin 1.0 (input pullup)
-    P1FUNC &= ~(1 << 0);
-    P1DIR |= (1 << 0);
-    P1PULL |= (1 << 0);
-    P1LVLSEL |= (1 << 0);
-    P1INTEN = (1 << 0);
-    P1CHSTA &= ~(1 << 0);
+        P1FUNC &= ~(1 << 0);
+        P1DIR |= (1 << 0);
+        P1PULL |= (1 << 0);
+        P1LVLSEL |= (1 << 0);
+        P1INTEN = (1 << 0);
+        P1CHSTA &= ~(1 << 0);
 #endif
+
+    if (capabilities & CAPABILITY_NFC_WAKE) {
+        P1FUNC &= ~(1 << 3);
+        P1DIR |= (1 << 3);
+        P1PULL |= (1 << 3);
+        P1LVLSEL |= (1 << 3);
+        P1INTEN = (1 << 3);
+        P1CHSTA &= ~(1 << 3);
+    }
+
     // sleepy
     sleepForMsec(t);
 #ifdef HAS_BUTTON
@@ -274,6 +286,11 @@ void doSleep(const uint32_t __xdata t) {
         wakeUpReason = WAKEUP_REASON_GPIO;
         P1CHSTA &= ~(1 << 0);
     }
+
+    if (P1CHSTA && (1 << 3) && capabilities & CAPABILITY_NFC_WAKE) {
+        wakeUpReason = WAKEUP_REASON_NFC;
+        P1CHSTA &= ~(1 << 3);
+    }
 #endif
 }
 

tag_fw/powermgt.h

@@ -82,6 +82,8 @@ extern void initPowerSaving(const uint16_t initialValue);
 
 extern uint8_t __xdata wakeUpReason;
 
+extern uint8_t __xdata capabilities;
+
 extern uint16_t __xdata nextCheckInFromAP;
 extern uint8_t __xdata dataReqLastAttempt;
 extern int8_t __xdata temperature;

tag_fw/proto.h

@@ -116,6 +116,7 @@ struct AvailDataReq {
 
 #define CAPABILITY_HAS_WAKE_BUTTON 0x20
 #define CAPABILITY_HAS_NFC 0x40
+#define CAPABILITY_NFC_WAKE 0x80
 
 #define DATATYPE_NOUPDATE 0
 #define DATATYPE_IMG_BMP 2

tag_fw/syncedproto.c

@@ -50,9 +50,6 @@ uint8_t __xdata currentChannel = 0;
 static uint8_t __xdata inBuffer[128] = {0};
 static uint8_t __xdata outBuffer[128] = {0};
 
-// get capabilities from main.c
-extern uint8_t __xdata capabilities;
-
 // tools
 static uint8_t __xdata getPacketType(const void *__xdata buffer) {
     const struct MacFcs *__xdata fcs = buffer;