diff --git a/RX_FSK/RX_FSK.ino b/RX_FSK/RX_FSK.ino
index 98b7eed..f061b08 100644
--- a/RX_FSK/RX_FSK.ino
+++ b/RX_FSK/RX_FSK.ino
@@ -1924,17 +1924,46 @@ void setup()
         // Display backlight on M5 Core2
         axp.setPowerOutPut(AXP192_DCDC3, AXP202_ON);
         axp.setDCDC3Voltage(3300);
+	// SetBusPowerMode(0):
+	// #define AXP192_GPIO0_CTL                        (0x90)
+	// #define AXP192_GPIO0_VOL                        (0x91)
+	// #define AXP202_LDO234_DC23_CTL                  (0x12)
+
+	// The axp class lacks a functino to set GPIO0 VDO to 3.3V (as is done by original M5Stack software)
+	// so do this manually (default value 2.8V did not have the expected effect :))
+	// data = Read8bit(0x91);
+        // write1Byte(0x91, (data & 0X0F) | 0XF0);
+	uint8_t reg;
+	Wire.beginTransmission((uint8_t)AXP192_SLAVE_ADDRESS);
+	Wire.write(AXP192_GPIO0_VOL);
+	Wire.endTransmission();
+	Wire.requestFrom(AXP192_SLAVE_ADDRESS, 1);
+	reg = Wire.read();
+	reg = (reg&0x0F) | 0xF0;
+	Wire.beginTransmission((uint8_t)AXP192_SLAVE_ADDRESS);
+	Wire.write(AXP192_GPIO0_VOL);
+	Wire.write(reg);
+	Wire.endTransmission();
+	// data = Read8bit(0x90);
+        // Write1Byte(0x90, (data & 0XF8) | 0X02)
+	axp.setGPIOMode(AXP_GPIO_0, AXP_IO_LDO_MODE);  // disable AXP supply from VBUS
         pmu_irq = 2; // IRQ pin is not connected on Core2
+	// data = Read8bit(0x12);         //read reg 0x12
+        // Write1Byte(0x12, data | 0x40);    // enable 3,3V => 5V booster
+	// this is done below anyway: axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
+
+        axp.adc1Enable(AXP202_ACIN_VOL_ADC1, 1);
+        axp.adc1Enable(AXP202_ACIN_CUR_ADC1, 1);
       } else {
         // GPS on T-Beam, buzzer on M5 Core2
         axp.setPowerOutPut(AXP192_LDO3, AXP202_ON);
+        axp.adc1Enable(AXP202_VBUS_VOL_ADC1, 1);
+        axp.adc1Enable(AXP202_VBUS_CUR_ADC1, 1);
       }
       axp.setPowerOutPut(AXP192_DCDC2, AXP202_ON);
       axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
       axp.setPowerOutPut(AXP192_DCDC1, AXP202_ON);
       axp.setDCDC1Voltage(3300);
-      axp.adc1Enable(AXP202_VBUS_VOL_ADC1, 1);
-      axp.adc1Enable(AXP202_VBUS_CUR_ADC1, 1);
       axp.adc1Enable(AXP202_BATT_CUR_ADC1, 1);
       if (sonde.config.button2_axp ) {
         if (pmu_irq != 2) {
diff --git a/RX_FSK/src/Display.cpp b/RX_FSK/src/Display.cpp
index 056c440..706e8f0 100644
--- a/RX_FSK/src/Display.cpp
+++ b/RX_FSK/src/Display.cpp
@@ -1693,11 +1693,19 @@ void Display::drawBatt(DispEntry *de) {
 		snprintf(buf, 30, "%.2f%s", val, de->extra+1);
 		break;
 	case 'U':
-		val = axp.getVbusVoltage();
+		if(sonde.config.type == TYPE_M5_CORE2) {
+		  val = axp.getAcinVoltage();
+		} else {
+		  val = axp.getVbusVoltage();
+		}
 		snprintf(buf, 30, "%.2f%s", val/1000, de->extra+1);
 		break;
 	case 'I':
-		val = axp.getVbusCurrent();
+		if(sonde.config.type == TYPE_M5_CORE2) {
+		  val = axp.getAcinCurrent();
+		} else {
+		  val = axp.getVbusCurrent();
+		}
 		snprintf(buf, 30, "%.2f%s", val, de->extra+1);
 		break;
 	case 'T':
diff --git a/RX_FSK/src/nav_gps_vel.cpp b/RX_FSK/src/nav_gps_vel.cpp
index 6d4f547..174ec5b 100644
--- a/RX_FSK/src/nav_gps_vel.cpp
+++ b/RX_FSK/src/nav_gps_vel.cpp
@@ -85,6 +85,15 @@ static EPHEM_t *te;
 #define fread(buffer, siz, els, file) (file.read((uint8_t *)buffer, (siz)*(els))/siz)
 #define fgetc(file) (char)file.read()
 
+int readDbl(File *fp, double *dbl) {
+    uint8_t buf[20];
+    int l = fp->read(buf, 19);
+    if(l!=19) return -1;
+    if (buf[15] == 'D') buf[15] = 'E';
+    buf[19] = 0; 
+    sscanf((char *)buf, "%lf", dbl); 
+    return 0;
+}
 
 EPHEM_t *read_RNXpephs(const char *file) {
     int l, i;
@@ -137,56 +146,84 @@ EPHEM_t *read_RNXpephs(const char *file) {
         strncpy(ephem.epoch+2, str, 15);
         ephem.epoch[16] = '\0';
 
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af0 = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af1 = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af2 = dbl;
+        if(readDbl(&fp, &dbl)<0) break; ephem.af0 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.af1 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.af2 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af0 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af1 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.af2 = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iode = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.crs = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.delta_n = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.M0 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.iode = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.crs = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.delta_n = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.M0 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iode = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.crs = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.delta_n = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.M0 = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cuc = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.e = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cus = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.sqrta = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.cuc = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.e = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.cus = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.sqrta = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cuc = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.e = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cus = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.sqrta = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.toe = dbl;
-                                                                                                                                    ephem.toc = ephem.toe;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cic = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.Omega0 = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cis = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.toe = dbl; ephem.toc = ephem.toe;
+	if(readDbl(&fp, &dbl)<0) break; ephem.cic = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.Omega0 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.cis = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.toe = dbl;
+        //                                                                                                                            ephem.toc = ephem.toe;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cic = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.Omega0 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.cis = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.i0 = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.crc = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.w = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.OmegaDot = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.i0 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.crc = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.w = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.OmegaDot = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.i0 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.crc = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.w = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.OmegaDot = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.idot = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.codeL2 = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.gpsweek = (int)dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iodc = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.idot = dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.codeL2 = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.gpsweek = (int)dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.iodc = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.idot = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.codeL2 = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.gpsweek = (int)dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iodc = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.sva = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.health = (uint8_t)(dbl+0.1);
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.tgd = dbl;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iodc = dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.sva = dbl;
+	if(readDbl(&fp, &dbl)<0) break; ephem.health = (uint8_t)(dbl+0.1);
+	if(readDbl(&fp, &dbl)<0) break; ephem.tgd = dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.iodc = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.sva = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.health = (uint8_t)(dbl+0.1);
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); ephem.tgd = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.iodc = dbl;
         while ((c=fgetc(fp)) != '\n') { if (c == EOF) break; }
 
         l = fread(buf,  3, 1, fp);    if (l != 1) break;  buf[ 3] = 0;
-        l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.ttom = dbl;
+	if(readDbl(&fp, &dbl)<0) break; //ephem.ttom = dbl;
+        //l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.ttom = dbl;
 	String l = fp.readStringUntil('\n');
      /* // die letzten beiden Felder (spare) sind manchmal leer (statt 0.00); manchmal fehlt sogar das drittletzte Feld
         l = fread(buf, 19, 1, fp);    if (l != 1) break;  if (buf[15] == 'D') buf[15] = 'E'; buf[19] = 0; sscanf(buf, "%lf", &dbl); //ephem.fit = dbl;