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Diffstat (limited to 'software/avr.lib/ds1820.c')
| -rw-r--r-- | software/avr.lib/ds1820.c | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/software/avr.lib/ds1820.c b/software/avr.lib/ds1820.c deleted file mode 100644 index 4619498..0000000 --- a/software/avr.lib/ds1820.c +++ /dev/null @@ -1,167 +0,0 @@ -/* - * spreadspace avr utils - usb-1wire example - * - * - * Copyright (C) 2013-2014 Bernhard Tittelbach <xro@realraum.at> - * based on code from: - * http://www.pjrc.com/teensy/td_libs_OneWire.html - * - * This file is part of spreadspace avr utils. - * - * spreadspace avr utils 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 - * any later version. - * - * spreadspace avr utils 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 spreadspace avr utils. If not, see <http://www.gnu.org/licenses/>. - */ - - -#include "ds1820.h" -#include "onewire.h" -#include "util/delay.h" - -uint8_t owi_ds1820_addr_[MAX_OWI_DEVICES][8]; -uint8_t num_ds1820_found_; - -uint8_t ds1820_discover(void) -{ - uint8_t d=0; - num_ds1820_found_ = 0; - if (! owi_reset()) //if no devices on bus, return now - return 0; - owi_reset_search(); - _delay_ms(250); - - //Search only for DS1820 temp sensors - owi_target_search(DS1820_FAMILY_ID); - - while ( owi_search(owi_ds1820_addr_[ d ])) - { - d++; - if ( d >= MAX_OWI_DEVICES) - break; - } - num_ds1820_found_ = d; - return num_ds1820_found_; -} - -void ds1820_set_resolution(uint8_t d, uint8_t bits) -{ - uint8_t resolution; - if (d >= num_ds1820_found_ || bits < 9 || bits > 12) - return; - - owi_reset(); - owi_select(owi_ds1820_addr_[d]); - - owi_write(DS1820_WRITE_SCRATCHPAD, 0); - owi_write(0xFF, 0); - owi_write(0x7F, 0); - - resolution = (bits - 9) << 5; - owi_write(resolution | 0x1F, 0); -} - -void ds1820_start_measuring(uint8_t d) -{ - owi_reset(); - owi_select(owi_ds1820_addr_[d]); - owi_write(DS1820_START_CONVERSION, 1); -} - -uint16_t ds1820_get_conversion_time_ms(uint8_t bits) -{ - switch (bits) - { - case 9: return DS1820_TCONV_MS_9BITS; - case 10: return DS1820_TCONV_MS_10BITS; - case 11: return DS1820_TCONV_MS_11BITS; - default: return DS1820_TCONV_MS_12BITS; - } -} - -void ds1820_wait_conversion_time(uint8_t bits) -{ - switch (bits) - { - case 9: _delay_ms(DS1820_TCONV_MS_9BITS); break; - case 10: _delay_ms(DS1820_TCONV_MS_10BITS); break; - case 11: _delay_ms(DS1820_TCONV_MS_11BITS); break; - default: _delay_ms(DS1820_TCONV_MS_12BITS); break; - } -} - -int16_t ds1820_read_temperature(uint8_t d) -{ - uint8_t data[9]; - int16_t raw = 0; - uint8_t type_s=0; - uint8_t cfg, i; - - owi_reset(); - owi_select(owi_ds1820_addr_[d]); - owi_write(DS1820_READ_SCRATCHPAD, 0); // Read Scratchpad - for (i = 0; i < 9; i++) { // we need 9 bytes - data[i] = owi_read(); - } - #if (ONEWIRE_CRC == 1) - uint8_t crc_result = owi_crc8(data,8); - if (crc_result != data[8]) - return DS1820_ERROR; - #endif - - // the first ROM byte indicates which chip - switch (owi_ds1820_addr_[d][0]) - { - case 0x10: - type_s = 1; - break; - case 0x28: - case 0x22: - type_s = 0; - break; - default: - break; - } - - // Convert the data to actual temperature - // because the result is a 16 bit signed integer, it should - // be stored to an "int16_t" type, which is always 16 bits - // even when compiled on a 32 bit processor. - raw = (data[1] << 8) | data[0]; - if (type_s) - { - raw = raw << 3; // 9 bit resolution default - if (data[7] == 0x10) { - // "count remain" gives full 12 bit resolution - raw = (raw & 0xFFF0) + 12 - data[6]; - } - } else { - cfg = (data[4] & 0x60); - // at lower res, the low bits are undefined, so let's zero them - if (cfg == DS1820_RESOLUTION_9BITS) - raw = raw & ~7; // 9 bit resolution, 93.75 ms - else if (cfg == DS1820_RESOLUTION_10BITS) - raw = raw & ~3; // 10 bit res, 187.5 ms - else if (cfg == DS1820_RESOLUTION_11BITS) - raw = raw & ~1; // 11 bit res, 375 ms - //// default is 12 bit resolution, 750 ms conversion time - } - - return raw; -} - -float ds1820_raw_temp_to_celsius(int16_t t) -{ - if ( t == DS1820_ERROR ) - return DS1820_ERROR; - else - return ((float) t) / 16.0; -} |