A library to interface to the MCP3208 SPI-based ADC from Microchip. This chip provides eight analogue inputs, providing converted 12-bit values via SPI.
Dependents: Nucleo_MCP3208_Test Nucleo_MCP3208_Ticker_Test BBMv2_eps ref_BBMv2_eps ... more
mcp3208.h@2:93009a423b45, 2011-05-24 (annotated)
- Committer:
- Kemp
- Date:
- Tue May 24 14:06:57 2011 +0000
- Revision:
- 2:93009a423b45
- Parent:
- 1:316f86115221
Updated documentation for public interface. Fixed the annoying bug with the library description.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
Kemp | 2:93009a423b45 | 1 | /** |
Kemp | 2:93009a423b45 | 2 | * @file mcp3208.h |
Kemp | 2:93009a423b45 | 3 | */ |
Kemp | 2:93009a423b45 | 4 | |
Kemp | 2:93009a423b45 | 5 | #include "mbed.h" |
Kemp | 2:93009a423b45 | 6 | |
Kemp | 2:93009a423b45 | 7 | |
Kemp | 2:93009a423b45 | 8 | #ifndef MCP3208_H |
Kemp | 2:93009a423b45 | 9 | #define MCP3208_H |
Kemp | 2:93009a423b45 | 10 | |
Kemp | 2:93009a423b45 | 11 | |
Kemp | 2:93009a423b45 | 12 | /** Polarity setting for differential inputs. |
Kemp | 2:93009a423b45 | 13 | * |
Kemp | 2:93009a423b45 | 14 | * POL_EVEN_POSITIVE sets channel [0|2|4|6] as the positive side and channel |
Kemp | 2:93009a423b45 | 15 | * [1|3|5|7] as the negative side. POL_EVEN_NEGATIVE sets the opposite. |
Kemp | 2:93009a423b45 | 16 | */ |
Kemp | 2:93009a423b45 | 17 | enum Polarity { |
Kemp | 2:93009a423b45 | 18 | POL_EVEN_POSITIVE, |
Kemp | 2:93009a423b45 | 19 | POL_EVEN_NEGATIVE |
Kemp | 2:93009a423b45 | 20 | }; |
Kemp | 2:93009a423b45 | 21 | |
Kemp | 2:93009a423b45 | 22 | |
Kemp | 2:93009a423b45 | 23 | /** Class for interfacing to the MCP3208 SPI-based ADC. |
Kemp | 2:93009a423b45 | 24 | * |
Kemp | 2:93009a423b45 | 25 | * This class will also allow interfacing to the MCP3204, but only four |
Kemp | 2:93009a423b45 | 26 | * inputs are provided by that chip, as opposed to the eight of the MCP3208. |
Kemp | 2:93009a423b45 | 27 | */ |
Kemp | 2:93009a423b45 | 28 | class MCP3208 |
Kemp | 2:93009a423b45 | 29 | { |
Kemp | 2:93009a423b45 | 30 | public: |
Kemp | 2:93009a423b45 | 31 | /** Create an MCP3208 object. |
Kemp | 2:93009a423b45 | 32 | * |
Kemp | 2:93009a423b45 | 33 | * @param bus An SPI bus object. |
Kemp | 2:93009a423b45 | 34 | * @param cs The name of a pin to use as the chip select. |
Kemp | 2:93009a423b45 | 35 | */ |
Kemp | 2:93009a423b45 | 36 | MCP3208(SPI bus, PinName cs); |
Kemp | 2:93009a423b45 | 37 | ~MCP3208(); |
Kemp | 2:93009a423b45 | 38 | |
Kemp | 2:93009a423b45 | 39 | /** Read from a single-ended input. |
Kemp | 2:93009a423b45 | 40 | * |
Kemp | 2:93009a423b45 | 41 | * @param channel The channel number to read from. |
Kemp | 2:93009a423b45 | 42 | * |
Kemp | 2:93009a423b45 | 43 | * @param returns The sampled value as a float between 0.0 and 1.0. |
Kemp | 2:93009a423b45 | 44 | */ |
Kemp | 2:93009a423b45 | 45 | float read_input(int channel); |
Kemp | 2:93009a423b45 | 46 | |
Kemp | 2:93009a423b45 | 47 | /** Read from a pair of differential inputs. |
Kemp | 2:93009a423b45 | 48 | * |
Kemp | 2:93009a423b45 | 49 | * In differential mode, the channels are referred to as 0 to 3, with |
Kemp | 2:93009a423b45 | 50 | * polarity set in a separate parameter. This avoids the user having to set |
Kemp | 2:93009a423b45 | 51 | * the polarity as part of the channel number or having channel numbers |
Kemp | 2:93009a423b45 | 52 | * increase by two (i.e. the channels being 0, 2, 4, and 6). |
Kemp | 2:93009a423b45 | 53 | * |
Kemp | 2:93009a423b45 | 54 | * @param channel The channel number to read from. |
Kemp | 2:93009a423b45 | 55 | * @param polarity The polarity of the differential signal. |
Kemp | 2:93009a423b45 | 56 | * |
Kemp | 2:93009a423b45 | 57 | * @param returns The sampled value as a float between 0.0 and 1.0. |
Kemp | 2:93009a423b45 | 58 | */ |
Kemp | 2:93009a423b45 | 59 | float read_diff_input(int channel, Polarity polarity); |
Kemp | 2:93009a423b45 | 60 | |
Kemp | 2:93009a423b45 | 61 | private: |
Kemp | 2:93009a423b45 | 62 | DigitalOut m_cs; |
Kemp | 2:93009a423b45 | 63 | SPI m_bus; |
Kemp | 2:93009a423b45 | 64 | |
Kemp | 2:93009a423b45 | 65 | void select(); |
Kemp | 2:93009a423b45 | 66 | void deselect(); |
Kemp | 2:93009a423b45 | 67 | }; |
Kemp | 2:93009a423b45 | 68 | |
Kemp | 2:93009a423b45 | 69 | |
Kemp | 2:93009a423b45 | 70 | #endif |