Add isPicoW call to RP2040 object (#1204)

Use the RPi code to get a best-guess as to whether the board is a Pico or
PicoW.

Fixes #849

Author: earlephilhower

cores/rp2040/RP2040Support.h

@@ -363,6 +363,16 @@ class RP2040 {
         return (uint32_t)rr;
     }
 
+    bool isPicoW() {
+#if !defined(ARDUINO_RASPBERRY_PI_PICO_W)
+        return false;
+#else
+        extern bool __isPicoW;
+        return __isPicoW;
+#endif
+    }
+
+
 private:
     static void _SystickHandler() {
         rp2040._epoch += 1LL << 24;

docs/rp2040.rst

@@ -75,6 +75,15 @@ Returns the total heap that was available to this program at compile time (i.e.
 the Pico RAM size minus things like the ``.data`` and ``.bss`` sections and other
 overhead).
 
+Hardware Identification
+-----------------------
+
+bool isPicoW()
+~~~~~~~~~~~~~~
+Returns the core's best guess if this code is running on a Raspberry Pi Pico W.
+This would let you, possibly, use the same UF2 for Pico and PicoW by simply not
+doing any WiFi calls.
+
 Bootloader
 ----------
 

keywords.txt

@@ -44,6 +44,8 @@ restartCore1	KEYWORD2
 reboot	KEYWORD2
 restart	KEYWORD2
 
+isPicoW	KEYWORD2
+
 getChipID	KEYWORD2
 
 hwrand32	KEYWORD2

variants/rpipicow/picow_init.cpp

@@ -19,11 +19,48 @@
 */
 
 #include <pico/cyw43_arch.h>
+#include "hardware/resets.h"
+#include "hardware/gpio.h"
+#include "hardware/adc.h"
 
 #ifndef WIFICC
 #define WIFICC CYW43_COUNTRY_WORLDWIDE
 #endif
 
+// Taken from https://datasheets.raspberrypi.com/picow/connecting-to-the-internet-with-pico-w.pdf
+// also discussion in https://github.com/earlephilhower/arduino-pico/issues/849
+static bool CheckPicoW() {
+    adc_init();
+    auto dir = gpio_get_dir(29);
+    auto fnc = gpio_get_function(29);
+    adc_gpio_init(29);
+    adc_select_input(3);
+    auto adc29 = adc_read();
+    gpio_set_function(29, fnc);
+    gpio_set_dir(29, dir);
+
+    dir = gpio_get_dir(25);
+    fnc = gpio_get_function(25);
+    gpio_init(25);
+    gpio_set_dir(25, GPIO_IN);
+    auto gp25 = gpio_get(25);
+    gpio_set_function(25, fnc);
+    gpio_set_dir(25, dir);
+
+    if (gp25) {
+        return true; // Can't tell, so assume yes
+    } else if (adc29 < 200) {
+        return true; // PicoW
+    } else {
+        return false;
+    }
+}
+
+bool __isPicoW = true;
+
 extern "C" void initVariant() {
-    cyw43_arch_init_with_country(WIFICC);
+    __isPicoW = CheckPicoW();
+    if (__isPicoW) {
+        cyw43_arch_init_with_country(WIFICC);
+    }
 }

variants/rpipicow/pins_arduino.h

@@ -3,9 +3,10 @@
 // Pin definitions taken from:
 //    https://datasheets.raspberrypi.org/pico/pico-datasheet.pdf
 
+extern bool  __isPicoW;
 
 // LEDs
-#define PIN_LED        (32u)
+#define PIN_LED        (__isPicoW ? 32u : 25u)
 
 // Serial
 #define PIN_SERIAL1_TX (0u)