LM74 temperature sensor Library on SPI I/F
TmpLM74.h@1:a29c5af6c1f0, 2011-03-11 (annotated)
- Committer:
- atpolitis
- Date:
- Fri Mar 11 09:55:23 2011 +0000
- Revision:
- 1:a29c5af6c1f0
- Parent:
- 0:9293a89e30e2
correction for negative temperarures
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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atpolitis | 0:9293a89e30e2 | 1 | /* mbed tmpLM74 Library, for a LM74 based digital thermometer |
atpolitis | 0:9293a89e30e2 | 2 | * Copyright (c) 2011, atpolitis, http://mbed.org |
atpolitis | 0:9293a89e30e2 | 3 | * |
atpolitis | 0:9293a89e30e2 | 4 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
atpolitis | 0:9293a89e30e2 | 5 | * of this software and associated documentation files (the "Software"), to deal |
atpolitis | 0:9293a89e30e2 | 6 | * in the Software without restriction, including without limitation the rights |
atpolitis | 0:9293a89e30e2 | 7 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
atpolitis | 0:9293a89e30e2 | 8 | * copies of the Software, and to permit persons to whom the Software is |
atpolitis | 0:9293a89e30e2 | 9 | * furnished to do so, subject to the following conditions: |
atpolitis | 0:9293a89e30e2 | 10 | * |
atpolitis | 0:9293a89e30e2 | 11 | * The above copyright notice and this permission notice shall be included in |
atpolitis | 0:9293a89e30e2 | 12 | * all copies or substantial portions of the Software. |
atpolitis | 0:9293a89e30e2 | 13 | * |
atpolitis | 0:9293a89e30e2 | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
atpolitis | 0:9293a89e30e2 | 15 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
atpolitis | 0:9293a89e30e2 | 16 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
atpolitis | 0:9293a89e30e2 | 17 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
atpolitis | 0:9293a89e30e2 | 18 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
atpolitis | 0:9293a89e30e2 | 19 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
atpolitis | 0:9293a89e30e2 | 20 | * THE SOFTWARE. |
atpolitis | 0:9293a89e30e2 | 21 | */ |
atpolitis | 0:9293a89e30e2 | 22 | |
atpolitis | 0:9293a89e30e2 | 23 | #ifndef MBED_TMPLM74_H |
atpolitis | 0:9293a89e30e2 | 24 | #define MBED_TMPLM74_H |
atpolitis | 0:9293a89e30e2 | 25 | |
atpolitis | 0:9293a89e30e2 | 26 | #include "mbed.h" |
atpolitis | 0:9293a89e30e2 | 27 | |
atpolitis | 0:9293a89e30e2 | 28 | #define INVALID_LM74_TEMP 0X961 |
atpolitis | 0:9293a89e30e2 | 29 | #define MAX_LM74_TEMP (INVALID_LM74_TEMP-1)*0.0625 |
atpolitis | 0:9293a89e30e2 | 30 | |
atpolitis | 0:9293a89e30e2 | 31 | /** An LM74 based digital thermometer |
atpolitis | 0:9293a89e30e2 | 32 | * |
atpolitis | 0:9293a89e30e2 | 33 | * Currently supports SPI peripheral interface |
atpolitis | 0:9293a89e30e2 | 34 | * |
atpolitis | 0:9293a89e30e2 | 35 | * @code |
atpolitis | 0:9293a89e30e2 | 36 | * #include "mbed.h" |
atpolitis | 0:9293a89e30e2 | 37 | * #include "tmpLM74.h" |
atpolitis | 0:9293a89e30e2 | 38 | * |
atpolitis | 0:9293a89e30e2 | 39 | * Serial pc(USBTX, USBRX); // tx, rx |
atpolitis | 0:9293a89e30e2 | 40 | * DigitalOut myled(LED1); |
atpolitis | 0:9293a89e30e2 | 41 | * |
atpolitis | 0:9293a89e30e2 | 42 | * TmpLM74 Temp74(p5, p6, p7, p8); |
atpolitis | 0:9293a89e30e2 | 43 | * |
atpolitis | 0:9293a89e30e2 | 44 | * // mbed connections: |
atpolitis | 0:9293a89e30e2 | 45 | * // mosi(p5) to LM74 pin 1, through 10k |
atpolitis | 0:9293a89e30e2 | 46 | * // miso(p6) to LM74 pin 1 |
atpolitis | 0:9293a89e30e2 | 47 | * // sclk(p7) to LM74 pin 2 |
atpolitis | 0:9293a89e30e2 | 48 | * // miso(p8) to LM74 pin 7 |
atpolitis | 0:9293a89e30e2 | 49 | * |
atpolitis | 0:9293a89e30e2 | 50 | * //TmpLM74.startLM74(); // CAN be used, but NOT necessary (invoked within readTemp(), if needed) |
atpolitis | 0:9293a89e30e2 | 51 | * |
atpolitis | 0:9293a89e30e2 | 52 | * int main() { |
atpolitis | 0:9293a89e30e2 | 53 | * |
atpolitis | 0:9293a89e30e2 | 54 | * float TempC; |
atpolitis | 0:9293a89e30e2 | 55 | * |
atpolitis | 0:9293a89e30e2 | 56 | * pc.printf("HELLO!, testing LM74 temperature sensor ...\n\r"); |
atpolitis | 0:9293a89e30e2 | 57 | * |
atpolitis | 0:9293a89e30e2 | 58 | * for (int i = 0; i < 10; i++){ |
atpolitis | 0:9293a89e30e2 | 59 | * wait(2); |
atpolitis | 0:9293a89e30e2 | 60 | * TempC = Temp74.readTemp(); |
atpolitis | 0:9293a89e30e2 | 61 | * pc.printf("Temperature = "); |
atpolitis | 0:9293a89e30e2 | 62 | * if(TempC > MAX_LM74_TEMP) { // check whether temp is valid |
atpolitis | 0:9293a89e30e2 | 63 | * pc.printf(" ? *C\n", TempC); |
atpolitis | 0:9293a89e30e2 | 64 | * } else { |
atpolitis | 0:9293a89e30e2 | 65 | * pc.printf("%3.1f *C\n", TempC); |
atpolitis | 0:9293a89e30e2 | 66 | * } |
atpolitis | 0:9293a89e30e2 | 67 | * myled = !myled; |
atpolitis | 0:9293a89e30e2 | 68 | * } |
atpolitis | 0:9293a89e30e2 | 69 | * Temp74.shutLM74down(); |
atpolitis | 0:9293a89e30e2 | 70 | * while(1){ |
atpolitis | 0:9293a89e30e2 | 71 | * wait(1); |
atpolitis | 0:9293a89e30e2 | 72 | * myled = !myled; |
atpolitis | 0:9293a89e30e2 | 73 | * } |
atpolitis | 0:9293a89e30e2 | 74 | * } |
atpolitis | 0:9293a89e30e2 | 75 | * @endcode |
atpolitis | 0:9293a89e30e2 | 76 | */ |
atpolitis | 0:9293a89e30e2 | 77 | // ******************************************************************** |
atpolitis | 0:9293a89e30e2 | 78 | // in this version, class TmpLM74 is derived from class SPI |
atpolitis | 0:9293a89e30e2 | 79 | // and inherits its members |
atpolitis | 0:9293a89e30e2 | 80 | // |
atpolitis | 0:9293a89e30e2 | 81 | // ******************************************************************** |
atpolitis | 0:9293a89e30e2 | 82 | |
atpolitis | 0:9293a89e30e2 | 83 | class TmpLM74: public SPI { |
atpolitis | 0:9293a89e30e2 | 84 | |
atpolitis | 0:9293a89e30e2 | 85 | public: |
atpolitis | 0:9293a89e30e2 | 86 | |
atpolitis | 0:9293a89e30e2 | 87 | TmpLM74(PinName mosi, PinName miso, PinName sclk, PinName csLM74); |
atpolitis | 0:9293a89e30e2 | 88 | |
atpolitis | 0:9293a89e30e2 | 89 | float readTemp(void); |
atpolitis | 0:9293a89e30e2 | 90 | void startLM74(void); |
atpolitis | 0:9293a89e30e2 | 91 | void shutLM74down(void); |
atpolitis | 0:9293a89e30e2 | 92 | |
atpolitis | 0:9293a89e30e2 | 93 | protected: |
atpolitis | 0:9293a89e30e2 | 94 | DigitalOut _csLM74; |
atpolitis | 0:9293a89e30e2 | 95 | }; |
atpolitis | 0:9293a89e30e2 | 96 | |
atpolitis | 0:9293a89e30e2 | 97 | #endif |