Maxim Integrated / DS1775_Digitial_Thermometer_Thermostat

C code and C++ library, driver software for Maxim Integrated DS1775, DS75 thermometer and thermostat temperature sensor. Code supports continuous or shut-down/standby, hysteresis, alarm limits, comparator or interrupt mode, fault filtering, and active low/high. Compact 5-pin SOT23 packaging

Dependents:   DS1775_Digital_Thermostat_Temperature

Diff: ds1775_cpp.cpp

Revision:
9:315236fb3c6a
Parent:
8:b2d4c71268aa
Child:
10:03645de9c017
diff -r b2d4c71268aa -r 315236fb3c6a ds1775_cpp.cpp
--- a/ds1775_cpp.cpp	Sun Apr 07 07:43:11 2019 +0000
+++ b/ds1775_cpp.cpp	Sun Apr 07 08:59:48 2019 +0000
@@ -56,6 +56,32 @@
 }
 
 /******************************************************************************/
+int DS1775::read_cfg_reg(uint8_t *value) 
+{
+    int32_t ret;
+    char data[1] = {0};
+    char reg = DS1775_REG_CONFIGURATION;
+
+    /* write to the Register Select, true is for repeated start */
+    ret = m_i2c.write(m_write_address, &reg, 1, true);
+    if (ret == 0) {
+        ret = m_i2c.read(m_read_address, data, 1, false);
+        if (ret == 0) {
+            *value = data[0];
+            printf("%s: cfg %x\r\n", __func__, *value);
+            return DS1775_NO_ERROR;
+        } else {
+            printf(
+                "%s: failed to read data: ret: %d\r\n", __func__, ret);
+            }
+    } else {                
+        printf("%s: failed to write to Register Select: ret: %d\r\n",
+            __func__, ret);
+    }
+    return DS1775_ERROR;
+}
+
+/******************************************************************************/
 int DS1775::read_reg(uint16_t *value, char reg) 
 {
     int32_t ret;
@@ -63,7 +89,7 @@
     ds1775_raw_data tmp;
      
     if (reg <= DS1775_REG_MAX) {
-        /* write to the Register Select */
+        /* write to the Register Select, true is for repeated start */
         ret = m_i2c.write(m_write_address, &reg, 1, true);
         /* read the two bytes of data */
         if (ret == 0) {
@@ -71,6 +97,8 @@
             if (ret == 0) {
                 tmp.msb = data[0];
                 tmp.lsb = data[1];
+                printf(
+                    "%s: MSB LSB %x %x\r\n", __func__, tmp.msb, tmp.lsb);
                 *value = tmp.uwrd;
                 return DS1775_NO_ERROR;
             } else {
@@ -125,11 +153,29 @@
         cmd[2] = tmp.lsb;
         ret = m_i2c.write(m_write_address, cmd, 3, false);
         if (ret == 0) {
-            if (DS1775_REG_CONFIGURATION == reg) {
-                m_extended_format = 0;
-                if (tmp.uwrd & DS1775_CFG_EXTENDED_FORMAT)
-                    m_extended_format = 1;
-            }
+            return DS1775_NO_ERROR;
+        } else {
+            printf("%s: I2C write error %d\r\n",__func__, ret);
+            return DS1775_ERROR;
+        }
+    } else {
+        printf("%s: register value invalid %x\r\n",__func__, reg);
+        return DS1775_ERROR;
+    }
+}
+
+/******************************************************************************/
+int DS1775::write_reg_one_byte(uint8_t value, char reg) 
+{
+    int32_t ret;
+    char cmd[2];
+    ds1775_raw_data tmp;
+
+    if (reg == DS1775_REG_CONFIGURATION) {
+        cmd[0] = reg;
+        cmd[1] = value;
+        ret = m_i2c.write(m_write_address, cmd, 2, false);
+        if (ret == 0) {
             return DS1775_NO_ERROR;
         } else {
             printf("%s: I2C write error %d\r\n",__func__, ret);
@@ -144,7 +190,7 @@
 /******************************************************************************/
 int DS1775::write_cfg(uint16_t cfg)
 {
-    return write_reg(cfg, DS1775_REG_CONFIGURATION);
+    return write_reg_one_byte(cfg, DS1775_REG_CONFIGURATION);
 }
 
 /******************************************************************************/