Sarah Marsh / TCA9548A

Driver for http://www.ti.com/lit/ds/symlink/tca9548a.pdf

Fork of TCA9548A by Akash Vibhute

tca9548a.h@2:1107ee23873a, 2017-12-12 (annotated)

Committer:
sarahmarshy
Date:
Tue Dec 12 22:14:58 2017 +0000
Revision:
2:1107ee23873a
Parent:
1:768491b5e55d 
Update address of control register. Add function for checking which I2C channel is set.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
akashvibhute 0:5bd73cede544 1 /** TCA9548A library
akashvibhute 0:5bd73cede544 2 *
akashvibhute 0:5bd73cede544 3 * @author Akash Vibhute
akashvibhute 0:5bd73cede544 4 * @author < akash . roboticist [at] gmail . com >
akashvibhute 0:5bd73cede544 5 * @version 0.1
akashvibhute 0:5bd73cede544 6 * @date May/24/2016
akashvibhute 0:5bd73cede544 7 *
akashvibhute 0:5bd73cede544 8 * @section LICENSE
akashvibhute 0:5bd73cede544 9 *
akashvibhute 0:5bd73cede544 10 * Copyright (c) 2015 Akash Vibhute
akashvibhute 0:5bd73cede544 11 *
akashvibhute 0:5bd73cede544 12 * Licensed under the Apache License, Version 2.0 (the "License");
akashvibhute 0:5bd73cede544 13 * you may not use this file except in compliance with the License.
akashvibhute 0:5bd73cede544 14 * You may obtain a copy of the License at
akashvibhute 0:5bd73cede544 15 * http://www.apache.org/licenses/LICENSE-2.0
akashvibhute 0:5bd73cede544 16 *
akashvibhute 0:5bd73cede544 17 * Unless required by applicable law or agreed to in writing, software
akashvibhute 0:5bd73cede544 18 * distributed under the License is distributed on an "AS IS" BASIS,
akashvibhute 0:5bd73cede544 19 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
akashvibhute 0:5bd73cede544 20 * See the License for the specific language governing permissions and
akashvibhute 0:5bd73cede544 21 * limitations under the License.
akashvibhute 0:5bd73cede544 22 *
akashvibhute 0:5bd73cede544 23 * The above copyright notice and this permission notice shall be included in
akashvibhute 0:5bd73cede544 24 * all copies or substantial portions of the Software.
akashvibhute 0:5bd73cede544 25 *
akashvibhute 0:5bd73cede544 26 *
akashvibhute 0:5bd73cede544 27 */
akashvibhute 0:5bd73cede544 28
akashvibhute 0:5bd73cede544 29 #ifndef TCA9548A_H
akashvibhute 0:5bd73cede544 30 #define TCA9548A_H
akashvibhute 0:5bd73cede544 31
akashvibhute 0:5bd73cede544 32 #include "mbed.h"
akashvibhute 0:5bd73cede544 33
akashvibhute 0:5bd73cede544 34 /** TCA9548A class
akashvibhute 0:5bd73cede544 35 *
akashvibhute 0:5bd73cede544 36 * @section DESCRIPTION
akashvibhute 0:5bd73cede544 37 * TCA9548A: Low-Voltage 8-Channel I2C Switch With Reset
akashvibhute 0:5bd73cede544 38 * The TCA9548A device has eight bidirectional translating switches that can be
akashvibhute 0:5bd73cede544 39 * controlled through the I2C bus. The SCL/SDA upstream pair fans out to eight
akashvibhute 0:5bd73cede544 40 * downstream pairs, or channels. Any individual SCn/SDn channel or combination
akashvibhute 0:5bd73cede544 41 * of channels can be selected, determined by the contents of the programmable
akashvibhute 0:5bd73cede544 42 * control register.
akashvibhute 0:5bd73cede544 43 *
akashvibhute 0:5bd73cede544 44 * The TCA9548A has a user 8 selectable address in the range 0x70 thru 0x77 (7-bit),
akashvibhute 0:5bd73cede544 45 * based on the configuration of Addr pins (A0, A1, A2). Default address is 0x70 for
akashvibhute 0:5bd73cede544 46 * A0:A2 pull down.
akashvibhute 0:5bd73cede544 47 *
akashvibhute 0:5bd73cede544 48 * Datasheet for TCA9548A can be found at:
akashvibhute 0:5bd73cede544 49 * http://www.ti.com/lit/ds/symlink/tca9548a.pdf
akashvibhute 0:5bd73cede544 50 *
akashvibhute 0:5bd73cede544 51 * Example:
akashvibhute 0:5bd73cede544 52 * @code
akashvibhute 0:5bd73cede544 53 * #include "mbed.h"
akashvibhute 0:5bd73cede544 54 * #include "LM75B.h"
akashvibhute 0:5bd73cede544 55 * #include "TCA9548A.h"
akashvibhute 0:5bd73cede544 56 *
akashvibhute 1:768491b5e55d 57 * TCA9548A i2c_sw(I2C_SDA, I2C_SCL); //default address 0x70 applied
akashvibhute 0:5bd73cede544 58 *
akashvibhute 0:5bd73cede544 59 * int main()
akashvibhute 0:5bd73cede544 60 * {
akashvibhute 0:5bd73cede544 61 * // By default TCA9548A performs a power on reset and all downstream ports are deselected
akashvibhute 0:5bd73cede544 62 *
akashvibhute 0:5bd73cede544 63 * i2c_sw.select(0); // select the channel 0
akashvibhute 0:5bd73cede544 64 * LM75B tmp0(I2C_SDA, I2C_SCL); // making instance after a branch of I2C bus (which is connecting the LM75B) enabled
akashvibhute 0:5bd73cede544 65 *
akashvibhute 0:5bd73cede544 66 * i2c_sw.select(1); // select the channel 1
akashvibhute 0:5bd73cede544 67 * LM75B tmp1(I2C_SDA, I2C_SCL); // making instance after a branch of I2C bus (which is connecting the LM75B) enabled
akashvibhute 0:5bd73cede544 68 *
akashvibhute 0:5bd73cede544 69 * while(1) {
akashvibhute 0:5bd73cede544 70 *
akashvibhute 0:5bd73cede544 71 * i2c_sw.select(0); // select the channel 0
akashvibhute 0:5bd73cede544 72 * printf( "%.3f\r\n", tmp0.read() );
akashvibhute 0:5bd73cede544 73 *
akashvibhute 0:5bd73cede544 74 * i2c_sw.select(1); // select the channel 1
akashvibhute 0:5bd73cede544 75 * printf( "%.3f\r\n", tmp1.read() );
akashvibhute 0:5bd73cede544 76 *
akashvibhute 0:5bd73cede544 77 * wait( 1.0 );
akashvibhute 0:5bd73cede544 78 * }
akashvibhute 0:5bd73cede544 79 * }
akashvibhute 0:5bd73cede544 80 * @endcode
akashvibhute 0:5bd73cede544 81 */
akashvibhute 0:5bd73cede544 82
akashvibhute 0:5bd73cede544 83 class TCA9548A
akashvibhute 0:5bd73cede544 84 {
akashvibhute 0:5bd73cede544 85 public:
akashvibhute 0:5bd73cede544 86
akashvibhute 0:5bd73cede544 87 /** Create a TCA9546A instance connected to specified I2C pins with specified address
akashvibhute 0:5bd73cede544 88 *
akashvibhute 0:5bd73cede544 89 * @param sda I2C-bus SDA pin
akashvibhute 0:5bd73cede544 90 * @param scl I2C-bus SCL pin
akashvibhute 0:5bd73cede544 91 * @param i2c_address I2C-bus address (default: 0x70)
akashvibhute 0:5bd73cede544 92 * @param reset TCA9546A reset pin (default: NC for simple pullup connected)
akashvibhute 0:5bd73cede544 93 * @param hz I2C bus frequency (default: 400kHz)
akashvibhute 0:5bd73cede544 94 */
sarahmarshy 2:1107ee23873a 95 TCA9548A( PinName sda, PinName scl, uint8_t i2c_address = 0x70, PinName resetPin = NC);
akashvibhute 0:5bd73cede544 96
akashvibhute 0:5bd73cede544 97 /** Selecting a channel
akashvibhute 0:5bd73cede544 98 *
akashvibhute 0:5bd73cede544 99 * Switch to commended downstream I2C channel
akashvibhute 0:5bd73cede544 100 *
akashvibhute 0:5bd73cede544 101 * @param channel channel number
akashvibhute 0:5bd73cede544 102 */
akashvibhute 0:5bd73cede544 103 void select(uint8_t channel);
sarahmarshy 2:1107ee23873a 104
sarahmarshy 2:1107ee23873a 105 /** Check which channel is enabled
sarahmarshy 2:1107ee23873a 106 *
sarahmarshy 2:1107ee23873a 107 */
sarahmarshy 2:1107ee23873a 108 char check_set_channel();
akashvibhute 0:5bd73cede544 109
akashvibhute 0:5bd73cede544 110 /** Reset TCA9546A
akashvibhute 0:5bd73cede544 111 *
akashvibhute 0:5bd73cede544 112 * Reset switch
akashvibhute 0:5bd73cede544 113 */
akashvibhute 0:5bd73cede544 114 void reset();
akashvibhute 0:5bd73cede544 115
akashvibhute 0:5bd73cede544 116
akashvibhute 0:5bd73cede544 117 private:
akashvibhute 0:5bd73cede544 118 I2C i2c_;
akashvibhute 0:5bd73cede544 119 DigitalOut reset_pin;
akashvibhute 0:5bd73cede544 120 uint8_t i2c_addr;
akashvibhute 0:5bd73cede544 121
akashvibhute 0:5bd73cede544 122 };
akashvibhute 0:5bd73cede544 123
akashvibhute 0:5bd73cede544 124 #endif // TCA9548A_H