From 17cf73595f77b2d1bfc0c767aa301098d4b7789d Mon Sep 17 00:00:00 2001
From: Theo Arends <11044339+arendst@users.noreply.github.com>
Date: Mon, 24 Jul 2023 14:28:57 +0200
Subject: [PATCH] Refactor MAX17043 driver

Refactor MAX17043 driver optional enable library (default off providing smaller footprint (-250 bytes)
---
 .../tasmota_xsns_sensor/xsns_110_max17043.ino | 52 +++++++++++++++++--
 1 file changed, 47 insertions(+), 5 deletions(-)

diff --git a/tasmota/tasmota_xsns_sensor/xsns_110_max17043.ino b/tasmota/tasmota_xsns_sensor/xsns_110_max17043.ino
index 9a4e235bd..4a90f0b13 100644
--- a/tasmota/tasmota_xsns_sensor/xsns_110_max17043.ino
+++ b/tasmota/tasmota_xsns_sensor/xsns_110_max17043.ino
@@ -41,19 +41,51 @@
  * 
 \*********************************************************************************************/
 
-#define XSNS_110      110
-#define XI2C_83       83          // See I2CDEVICES.md
+#define XSNS_110           110
+#define XI2C_83            83      // See I2CDEVICES.md
+
+#define MAX17043_ADDRESS   0x36
+
+//#define MAX17043_USE_LIB
+
+#ifdef MAX17043_USE_LIB
 
 #include "DFRobot_MAX17043.h"
+DFRobot_MAX17043 max17043_gauge;   // Class to read from MAX17043
+
+#else
+
+#define MAX17043_VCELL     0x02
+#define MAX17043_SOC       0x04
+#define MAX17043_MODE      0x06
+#define MAX17043_VERSION   0x08
+#define MAX17043_CONFIG    0x0c
+#define MAX17043_COMMAND   0xfe
+
+#endif  // MAX17043_USE_LIB
 
-DFRobot_MAX17043 max17043_gauge;  // Class to read from MAX17043
 bool max17043 = false;
 
 /*********************************************************************************************/
 
 void Max17043Init(void) {
   if (I2cSetDevice(MAX17043_ADDRESS)) { 
+
+#ifdef MAX17043_USE_LIB
+
     if (max17043_gauge.begin() == 0) {
+
+#else
+
+    I2cWrite16(MAX17043_ADDRESS, MAX17043_COMMAND, 0x5400);        // Power on reset
+    delay(10);
+    if (I2cRead16(MAX17043_ADDRESS, MAX17043_CONFIG) == 0x971c) {  // Default 0x971c
+      I2cWrite16(MAX17043_ADDRESS, MAX17043_MODE, 0x4000);         // Quick start
+      I2cWrite16(MAX17043_ADDRESS, MAX17043_CONFIG, 0x9700);
+      delay(10);
+
+#endif  // MAX17043_USE_LIB
+
       max17043 = true;
       I2cSetActiveFound(MAX17043_ADDRESS, "MAX17043");
     }
@@ -61,13 +93,23 @@ void Max17043Init(void) {
 }
 
 void Max17043Show(bool json) {
+
+#ifdef MAX17043_USE_LIB
+
   float voltage = max17043_gauge.readVoltage() / 1000.0;  // Battery voltage in Volt
+  float percentage = max17043_gauge.readPercentage();     // Battery remaining charge in percent
+
+#else
+
+  float voltage = (1.25f * (float)(I2cRead16(MAX17043_ADDRESS, MAX17043_VCELL) >> 4)) / 1000.0;  // Battery voltage in Volt
+  uint16_t per = I2cRead16(MAX17043_ADDRESS, MAX17043_SOC);
+  float percentage = (float)((per >> 8) + 0.003906f * (per & 0x00ff));  // Battery remaining charge in percent
+
+#endif  // MAX17043_USE_LIB
 
   // During charging the percentage might be (slightly) above 100%. To avoid strange numbers
   // in the statistics the percentage provided by this driver will not go above 100%
-  float percentage = max17043_gauge.readPercentage();     // Battery remaining charge in percent
   if (percentage > 100.0) { percentage = 100.0; }
-
   if (json) {
     ResponseAppend_P(PSTR(",\"MAX17043\":{\"" D_JSON_VOLTAGE "\":%3_f,\"" D_JSON_BATTPERCENT "\":%2_f}"), &voltage, &percentage );
 #ifdef USE_WEBSERVER