Definitions for new Vpp measurment algorithm

aftb_adcparms.h

@@ -0,0 +1,45 @@
+/*
+ * Parameters for new varVppMeasureVpp()
+ * Select the data set that matches your hardware variant or add a suitable data set.
+ * 2024-02-14 Initial release
+ */
+#ifndef __AFTB_ADCPARMS_H__
+#define __AFTB_ADCPARMS_H__
+
+// Select your hardware version (AREF source)
+#define AREF_1V1            // Defined data sets AREF_3V3, AREF_1V1, AREF_3V3_R4
+// For best results, measure the voltage on AREF pin with a good multimeter and use this value for VREF
+
+#if defined(AREF_3V3)
+// Values for ATmega328P (NANO V3, UNO R3) AREF = EXTERNAL R7 = 3k3, Ri = 32k (original Afterburner)
+#define ADC_R5 (100.0)      // R5 in kOhm as float
+#define ADC_R6 (20.0)       // R6 in kOhm as float
+#define VREF (3.0)          // Vref in Volts as float; Vref = 3.3V * 32k / (32k + 3k3) => 2.991V
+#define AREF_SOURCE EXTERNAL
+
+#elif defined(AREF_1V1)
+// Values for ATmega328P (NANO V3, UNO R3) AREF = INTERNAL 1.1V, R5 = 20k, R6 = 1k3, R7 not populated
+#define ADC_R5 (20.0)       // R5 in kOhm as float
+#define ADC_R6 (1.3)        // R6 in kOhm as float
+#define VREF (1.1)          // Vref in Volts as float; Vref = 1.1V
+#define AREF_SOURCE INTERNAL
+
+#elif defined(AREF_3V3_R4)
+// Values for Renesas RA4M1 (UNO R4 Minima/WiFi) AREF = EXTERNAL R7 = 3k3, Ri = 130k (original Afterburner)
+#define ADC_R5 (100.0)      // R5 in kOhm as float
+#define ADC_R6 (20.0)       // R6 in kOhm as float
+#define VREF (3.2)          // Vref in Volts as float; Vref = 3.3V * 130k / (130k + 3k3) => 3.218V
+#define AREF_SOURCE AR_EXTERNAL
+
+// You can add additional variants here
+
+#else
+// Invalid or missing AREF variant
+#undef ADC_R5
+#undef ADC_R6
+#undef VREF
+#undef AREF_SOURCE
+#error "Invalid or missing AREF variant\n"
+#endif
+
+#endif