Mercurial > mbsePi-apps / file comparison
comparison: lib/dht11.c
lib/dht11.c
- changeset 36
- 8701b4dab77b
- parent 32
- 3bac8fd4173d
equal
deleted
inserted
replaced
| 35:f3c5ae78b746 | 36:8701b4dab77b |
|---|---|
| 118 * If there is no sensor, j = 0 | 118 * If there is no sensor, j = 0 |
| 119 */ | 119 */ |
| 120 if ((counter == 255) && (j == 0)) { | 120 if ((counter == 255) && (j == 0)) { |
| 121 if (dht11_temperature != -1) { | 121 if (dht11_temperature != -1) { |
| 122 syslog(LOG_NOTICE, "dht11 sensor disappeared"); | 122 syslog(LOG_NOTICE, "dht11 sensor disappeared"); |
| 123 } else { | |
| 124 syslog(LOG_NOTICE, "dht11 sensor not present"); | |
| 123 } | 125 } |
| 124 dht11_temperature = -1; | 126 dht11_temperature = -1; |
| 125 dht11_humidity = -1; | 127 dht11_humidity = -1; |
| 126 dht11_valid = false; | 128 dht11_valid = false; |
| 127 } else { | 129 return; |
| 130 } | |
| 128 | 131 |
| 129 /* | 132 /* |
| 130 * check we read 40 bits (8bit x 5 ) + verify checksum in the last byte | 133 * check we read 40 bits (8bit x 5 ) + verify checksum in the last byte |
| 131 * print it out if data is good | 134 * print it out if data is good |
| 132 */ | 135 */ |
| 133 if ((j >= 40) && (dht11_dat[4] == ((dht11_dat[0] + dht11_dat[1] + dht11_dat[2] + dht11_dat[3]) & 0xFF))) { | 136 if ((j >= 40) && (dht11_dat[4] == ((dht11_dat[0] + dht11_dat[1] + dht11_dat[2] + dht11_dat[3]) & 0xFF))) { |
| 134 got_correct_data = 1; | 137 got_correct_data = 1; |
| 135 | 138 |
| 136 int h = dht11_dat[0] + dht11_dat[1]; | 139 int h = dht11_dat[0] + dht11_dat[1]; |
| 137 int t = (dht11_dat[2] & 0x7F) + dht11_dat[3]; | 140 int t = (dht11_dat[2] & 0x7F) + dht11_dat[3]; |
| 138 t += dht11_t_offset; | 141 t += dht11_t_offset; |
| 142 t *= -1; | 145 t *= -1; |
| 143 | 146 |
| 144 dht11_temperature = t; | 147 dht11_temperature = t; |
| 145 dht11_humidity = h; | 148 dht11_humidity = h; |
| 146 dht11_valid = true; | 149 dht11_valid = true; |
| 147 } else { | 150 } else { |
| 148 tries--; | 151 tries--; |
| 149 if (tries == 0) | 152 if (tries == 0) |
| 150 syslog(LOG_INFO, "dht11 data checksum was wrong 5 times"); | 153 syslog(LOG_INFO, "dht11 data checksum was wrong 5 times"); |
| 151 usleep(100000); | 154 usleep(100000); |
| 152 } | |
| 153 } | 155 } |
| 154 } | 156 } |
| 155 } | 157 } |
| 156 | 158 |
| 157 | 159 |
