Add SI7005

I2Csensors/SI7005.c

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2025 Edward V. Emelianov <edward.emelianoff@gmail.com>.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <usefull_macros.h>
+
+#include "i2c.h"
+#include "SI7005.h"
+
+static uint8_t addr = 0x40;
+static double Tmeasured, Hmeasured;
+static sensor_status_t status = SENS_NOTINIT;
+
+#define SI7005_REGSTATUS    0
+#define SI7005_STATUSNRDY   1
+#define SI7005_REGDATA      1
+#define SI7005_REGCONFIG    3
+#define SI7005_CONFFAST     (1<<5)
+#define SI7005_CONFTEMP     (1<<4)
+#define SI7005_CONFHEAT     (1<<1)
+#define SI7005_CONFSTART    (1<<0)
+#define SI7005_REGID        0x11
+
+#define SI7005_ID           0x50
+
+static int s_init(){
+    uint8_t ID;
+    status = SENS_NOTINIT;
+    if(!i2c_read_reg8(SI7005_REGID, &ID)){
+        DBG("Can't read SI_REG_ID");
+        return FALSE;
+    }
+    DBG("SI, device ID: 0x%02x", ID);
+    if(ID != SI7005_ID){
+        DBG("Not SI7005\n");
+        return FALSE;
+    }
+    status = SENS_RELAX;
+    return TRUE;
+}
+
+static int s_start(){
+    if(status != SENS_RELAX) return FALSE;
+    status = SENS_BUSY;
+    if(!i2c_write_reg8(SI7005_REGCONFIG, SI7005_CONFTEMP | SI7005_CONFSTART)){
+        DBG("Can't write start Tmeas");
+        status = SENS_ERR;
+        return FALSE;
+    }
+    DBG("Wait for T\n");
+    return TRUE;
+}
+
+// start humidity measurement
+static sensor_status_t si7005_cmdH(){
+    status = SENS_BUSY;
+    if(!i2c_write_reg8(SI7005_REGCONFIG, SI7005_CONFSTART)){
+        DBG("Can't write start Hmeas");
+        return (status = SENS_ERR);
+    }
+    DBG("Wait for H");
+    return status;
+}
+
+static sensor_status_t s_process(){
+    uint8_t c, d[3];
+    if(status != SENS_BUSY) return status;
+    if(!i2c_read_raw(d, 3)){
+        DBG("Can't read status");
+        return (status = SENS_ERR);
+    }
+    //DBG("Status: 0x%02x, H: 0x%02x, L: 0x%02x", d[0], d[1], d[2]);
+    if(!i2c_read_reg8(SI7005_REGCONFIG, &c)){
+        DBG("Can't read config");
+        return (status = SENS_ERR);
+    }
+    //DBG("Config: 0x%02x", c);
+    if(d[0] & SI7005_STATUSNRDY){ // not ready yet
+        return status;
+    }
+    uint16_t TH = (uint16_t)((d[1]<<8) | d[2]);
+    if(c & SI7005_CONFTEMP){ // temperature measured
+        TH >>= 2;
+        Tmeasured = TH/32. - 50.;
+        DBG("T=%.2f", Tmeasured);
+        return si7005_cmdH();
+    }else{ // humidity measured
+        TH >>= 4;
+        Hmeasured = TH/16.f - 24.f;
+        DBG("H=%.1f", Hmeasured);
+        status = SENS_RDY;
+    }
+    return status;
+}
+
+static int s_getdata(sensor_data_t *d){
+    if(!d || status != SENS_RDY) return FALSE;
+    DBG("Measured T=%.1f, H=%.1f", Tmeasured, Hmeasured);
+    // correct T/H
+#define A0 (-4.7844)
+#define A1 (0.4008)
+#define A2 (-0.00393)
+    d->H = Hmeasured - (A2*Hmeasured*Hmeasured + A1*Hmeasured + A0);
+    d->T = Tmeasured;
+    status = SENS_RELAX;
+    return TRUE;
+}
+
+// turn heater on/off (1/0)
+static int s_heater(int on){
+    DBG("status=%d", status);
+    if(status != SENS_RELAX) return FALSE;
+    uint8_t reg = (on) ? SI7005_CONFHEAT : 0;
+    if(!i2c_write_reg8(SI7005_REGCONFIG, reg)){
+        DBG("Can't write regconfig");
+        return FALSE;
+    }
+    return TRUE;
+}
+
+static sensor_props_t s_props(){
+    sensor_props_t p = {.T = 1, .H = 1, .htr = 1};
+    return p;
+}
+
+static uint8_t address(uint8_t new){
+    if(new) addr = new;
+    return addr;
+}
+
+sensor_t SI7005 = {
+    .name = "SI7005",
+    .address = address,
+    .init = s_init,
+    .start = s_start,
+    .heater = s_heater,
+    .process = s_process,
+    .properties = s_props,
+    .get_data = s_getdata
+};