PSRAM support added to hal files

src/hal/fipy.h

@@ -3,6 +3,7 @@
 #define CFG_sx1272_radio 1
 #define HAS_LED NOT_A_PIN // FiPy has no on board LED, so we use RGB LED
 #define HAS_RGB_LED   GPIO_NUM_0  // WS2812B RGB LED on GPIO0
+#define BOARD_HAS_PSRAM // use extra 4MB extern RAM
 
 // Hardware pin definitions for Pycom FiPy board
 #define PIN_SPI_SS    GPIO_NUM_18

src/hal/lopy4.h

@@ -3,6 +3,7 @@
 #define CFG_sx1276_radio 1
 #define HAS_LED NOT_A_PIN // LoPy4 has no on board LED, so we use RGB LED on LoPy4
 #define HAS_RGB_LED   GPIO_NUM_0  // WS2812B RGB LED on GPIO0
+#define BOARD_HAS_PSRAM // use extra 4MB extern RAM
 
 // Hardware pin definitions for Pycom LoPy4 board
 #define PIN_SPI_SS    GPIO_NUM_18

src/hal/ttgobeam.h

@@ -1,6 +1,7 @@
 // Hardware related definitions for TTGO T-Beam board
 
 #define CFG_sx1276_radio 1 // HPD13A LoRa SoC
+#define BOARD_HAS_PSRAM // use extra 4MB extern RAM
 
 #define HAS_LED GPIO_NUM_21 // on board green LED_G1
 //#define HAS_BUTTON GPIO_NUM_39 // on board button "BOOT" (next to reset button) !! seems not to work!!