1 files changed, 155 insertions, 0 deletions
diff --git a/src/hih61xx.c b/src/hih61xx.c
new file mode 100644
index 0000000..b68b653
--- /dev/null
+++ b/src/hih61xx.c
@@ -0,0 +1,155 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+
+#include "hih61xx.h"
+
+extern int file;
+extern void bus_err(int ern);
+extern void print_help(void);
+unsigned char buf[5];
+
+
+
+
+void hih61xx_list_all(void)
+{
+    printf(
+        "00: Relative Humidity [%%]     (reg: 0x00)\n"
+        "01: Temperature       [°C]     (reg: 0x00)\n"
+        "02: Status            [hex]    (reg: 0x00)\n"
+        "\n");
+}
+
+
+
+void hih61xx_get_data(void)
+{
+    buf[0] = 0x00;
+    
+    if(write(file, buf, 1) != 1)    //Start measure
+    {
+        bus_err(errno);
+    }
+
+    usleep(60*1000);  // Wait 60ms for measurement
+    
+    if(read(file, buf, 4) != 4)  //Read the data
+    {
+        bus_err(errno);
+    } 
+}
+
+
+
+unsigned char hih61xx_read_status(void)
+{
+    return ((buf[0] & 0xc0) >> 6);
+}
+
+
+
+float hih61xx_read_humidity(float offset)
+{
+    unsigned int  raw = 0;
+    float  humidity;
+   
+    if(hih61xx_read_status() != 0x01 )
+    {
+        raw = ((buf[0] & 0x3f) << 8) + buf[1];      // two msb status, 14bit data
+        humidity = ((float)raw/(16384 - 2))*100;    // humidity = (14bit data / (2^14 -2)) * 100%
+    }
+    else
+    {
+        humidity = -1.0 ;
+    }
+    
+    return (humidity + offset) ;
+}
+
+
+
+float hih61xx_read_temp(float offset)
+{
+    unsigned int  raw = 0;
+    float  temp;
+   
+    if(hih61xx_read_status() != 0x01 )
+    {
+        raw = ((buf[2] << 8) + buf[1]) >> 2;        // 14bit temp data
+        temp = ((float)raw/(16384 - 2))*165 - 40 ;    // temp = ((14bit data / (2^14 -2))*165) - 40 [°C] 
+    }
+    else
+    {
+        temp = -40.0 ;
+    }
+ 
+    return (temp + offset);
+}
+
+
+
+void hih61xx_read_all(const char *opts)
+{
+    hih61xx_get_data();
+    
+    if(opts != NULL)
+    {
+        char *ptr;
+        printf("00:%f\n", hih61xx_read_humidity(strtof(opts, &ptr)));
+        
+        ptr++;               // One (,) character allowed for delimiter
+        
+        printf("01:%f\n", hih61xx_read_temp(strtof(ptr, NULL)));
+    }     
+    else
+    {
+        printf("00:%f\n", hih61xx_read_humidity(0.0));
+        printf("01:%f\n", hih61xx_read_temp(0.0));
+    }     
+
+    printf("02:0x%x\n", hih61xx_read_status()); 
+  
+}
+
+
+
+void hih61xx_read_one(const char *opts)
+{
+    int id;
+    char *ptr;
+ 
+    hih61xx_get_data();
+    id = strtol (opts,&ptr,0); //all format allowed
+    ptr++;      //one separator allowed
+        
+    switch (id)
+    {
+        case 0x00:
+            printf("00:%f\n", hih61xx_read_humidity(strtof(ptr, NULL)));
+            break;
+        case 0x01:
+            printf("01:%f\n", hih61xx_read_temp(strtof(ptr, NULL)));
+            break;
+        case 0x02:
+            printf("02:0x%x\n", hih61xx_read_status()); 
+            break;
+        default:
+            print_help();
+    } 
+}    
+
+
+
+
+
+
+
+
+
+
+