restructuring

F1:F103/SI7005_HTU21D/si7005.c

@@ -0,0 +1,162 @@
+/*
+ * This file is part of the si7005 project.
+ * Copyright 2021 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 "i2c.h"
+#include "si7005.h"
+
+#ifdef EBUG
+#include "usb.h"
+#include "proto.h"
+#define DBG(x)  do{USB_send(x);}while(0)
+#else
+#define DBG(x)
+#endif
+
+
+#define DEVID  (0x40)
+
+typedef enum{
+	RELAX = 0,
+	WAITFORT,       // T
+	WAITFORH        // humidity
+} si7005_state;
+
+static si7005_state state = RELAX;
+static si7005_status sistatus = SI7005_RELAX;
+static uint16_t TH; // data for T or H
+
+si7005_status si7005_get_status(){
+    return sistatus;
+}
+
+void si7005_setup(){
+    sistatus = SI7005_RELAX;
+    state = RELAX;
+	i2c_setup();
+	i2c_set_addr7(DEVID);
+}
+
+/**
+ * @brief si7005_read_ID - read device ID
+ * @param devid (o) - ID
+ * @return 1 if all OK
+ */
+int si7005_read_ID(uint8_t *devid){
+	uint8_t ID;
+	i2c_status st = I2C_OK;
+	if(state != RELAX){ // measurements are in process
+		return 0;
+	}
+    sistatus = SI7005_RELAX;
+	if((st = i2c_7bit_send_onebyte(0x11, 0)) == I2C_OK){
+		if((st = i2c_7bit_receive_onebyte(&ID, 1)) == I2C_OK){
+            *devid = ID;
+            return 1;
+		}
+	}
+    return 0;
+}
+
+/*
+ * start themperature reading @return 0 if all OK
+ */
+int si7005_cmdT(){
+	const uint8_t cmd[2] = {0x03, 0x11};
+	if(state != RELAX){
+		return 1;
+	}
+    sistatus = SI7005_BUSY;
+	i2c_status st = i2c_7bit_send(cmd, 2);
+	if(st != I2C_OK){
+        sistatus = SI7005_ERR;
+		return 1;
+	}
+    DBG("Wait for T\n");
+	state = WAITFORT;
+    return 0;
+}
+
+/*
+ * start humidity reading @return 0 if all OK
+ */
+int si7005_cmdH(){
+	const uint8_t cmd[2] = {0x03, 0x01};
+	if(state != RELAX){
+		return 1;
+	}
+    sistatus = SI7005_BUSY;
+	i2c_status st = i2c_7bit_send(cmd, 2);
+	if(st != I2C_OK){
+        sistatus = SI7005_ERR;
+		return 1;
+	}
+	state = WAITFORH;
+    DBG("Wait for H\n");
+    return 0;
+}
+
+int32_t si7005_getT(){ // T*10
+    if(sistatus != SI7005_TRDY) return -5000;
+    DBG("TH="); DBG(u2str(TH)); DBG("\n");
+    TH >>= 2;
+    uint32_t d = (TH*10)/32 - 500;
+    sistatus = SI7005_RELAX;
+    return d;
+}
+uint32_t si7005_getH(){ // hum * 10
+    if(sistatus != SI7005_HRDY) return 5000;
+    TH >>= 4;
+    uint32_t d = (TH*10)/16 - 240;
+    sistatus = SI7005_RELAX;
+    return d;
+}
+
+/*
+ * process state machine
+ */
+void si7005_process(){
+	uint8_t b, d[2];
+	i2c_status st;
+	if(state == RELAX) return;
+	if(state == WAITFORH || state == WAITFORT){ // poll RDY
+        DBG("Poll\n");
+		if((st = i2c_7bit_send_onebyte(0, 0)) == I2C_OK){
+            DBG("0 sent\n");
+			if(i2c_7bit_receive_onebyte(&b, 1) == I2C_OK){
+                DBG("received: "); DBG(u2str(b)); DBG("\n");
+				if(b) return; // !RDY
+                if((st = i2c_7bit_send_onebyte(1, 0)) == I2C_OK){
+                    DBG("sent 1\n");
+                    if((st = i2c_7bit_receive_twobytes(d)) == I2C_OK){
+                        DBG("got data: ");
+                        DBG(u2str(d[0])); DBG(" "); DBG(u2str(d[1])); DBG("\n");
+                        sistatus = (state == WAITFORH) ? SI7005_HRDY : SI7005_TRDY;
+                        TH = (d[0]<<8) | d[1];
+                    }
+                }
+				state = RELAX;
+				if(st != I2C_OK){
+					sistatus = SI7005_ERR;
+				}
+			}
+		}else{
+			state = RELAX;
+            sistatus = SI7005_ERR;
+		}
+	}
+}