Chris Styles
/
EA_RotaryEncoder
This example positions a lit LED in the I2C LED array using the rotary encoder
PCA9532.cpp@0:498b9b4a7bb9, 2010-03-02 (annotated)
- Committer:
- chris
- Date:
- Tue Mar 02 08:27:23 2010 +0000
- Revision:
- 0:498b9b4a7bb9
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
chris | 0:498b9b4a7bb9 | 1 | /* |
chris | 0:498b9b4a7bb9 | 2 | PCA9532 |
chris | 0:498b9b4a7bb9 | 3 | (c) 2009, cstyles |
chris | 0:498b9b4a7bb9 | 4 | */ |
chris | 0:498b9b4a7bb9 | 5 | |
chris | 0:498b9b4a7bb9 | 6 | #include "PCA9532.h" |
chris | 0:498b9b4a7bb9 | 7 | #include "mbed.h" |
chris | 0:498b9b4a7bb9 | 8 | |
chris | 0:498b9b4a7bb9 | 9 | /* |
chris | 0:498b9b4a7bb9 | 10 | Constructor, pin names for I2C and the I2C addrss of the device |
chris | 0:498b9b4a7bb9 | 11 | */ |
chris | 0:498b9b4a7bb9 | 12 | |
chris | 0:498b9b4a7bb9 | 13 | |
chris | 0:498b9b4a7bb9 | 14 | PCA9532::PCA9532(PinName scl, PinName sda, int addr) |
chris | 0:498b9b4a7bb9 | 15 | : _i2c(scl, sda) { |
chris | 0:498b9b4a7bb9 | 16 | |
chris | 0:498b9b4a7bb9 | 17 | _addr = addr; |
chris | 0:498b9b4a7bb9 | 18 | |
chris | 0:498b9b4a7bb9 | 19 | } |
chris | 0:498b9b4a7bb9 | 20 | |
chris | 0:498b9b4a7bb9 | 21 | |
chris | 0:498b9b4a7bb9 | 22 | |
chris | 0:498b9b4a7bb9 | 23 | |
chris | 0:498b9b4a7bb9 | 24 | |
chris | 0:498b9b4a7bb9 | 25 | /* |
chris | 0:498b9b4a7bb9 | 26 | force the LEDs on or off according to thier corresponding bits |
chris | 0:498b9b4a7bb9 | 27 | in the vector |
chris | 0:498b9b4a7bb9 | 28 | */ |
chris | 0:498b9b4a7bb9 | 29 | |
chris | 0:498b9b4a7bb9 | 30 | void PCA9532::write (int leds) { |
chris | 0:498b9b4a7bb9 | 31 | |
chris | 0:498b9b4a7bb9 | 32 | // cycle through the array |
chris | 0:498b9b4a7bb9 | 33 | for (int i=0; i < 16; i++) { |
chris | 0:498b9b4a7bb9 | 34 | |
chris | 0:498b9b4a7bb9 | 35 | // if the ith bit is '1' |
chris | 0:498b9b4a7bb9 | 36 | if (leds & (0x1 << i)) { |
chris | 0:498b9b4a7bb9 | 37 | _rmw(i,PCA9532_MODE_SET); |
chris | 0:498b9b4a7bb9 | 38 | } |
chris | 0:498b9b4a7bb9 | 39 | |
chris | 0:498b9b4a7bb9 | 40 | else { |
chris | 0:498b9b4a7bb9 | 41 | _rmw(i,PCA9532_MODE_CLEAR); |
chris | 0:498b9b4a7bb9 | 42 | } |
chris | 0:498b9b4a7bb9 | 43 | } |
chris | 0:498b9b4a7bb9 | 44 | } |
chris | 0:498b9b4a7bb9 | 45 | |
chris | 0:498b9b4a7bb9 | 46 | |
chris | 0:498b9b4a7bb9 | 47 | |
chris | 0:498b9b4a7bb9 | 48 | /* |
chris | 0:498b9b4a7bb9 | 49 | this is one hot encoding for the LED array |
chris | 0:498b9b4a7bb9 | 50 | any bit set will have it's corresponding LED switched on |
chris | 0:498b9b4a7bb9 | 51 | */ |
chris | 0:498b9b4a7bb9 | 52 | |
chris | 0:498b9b4a7bb9 | 53 | void PCA9532::set (int leds) { |
chris | 0:498b9b4a7bb9 | 54 | for (int i=0; i < 16; i++) { |
chris | 0:498b9b4a7bb9 | 55 | if (leds & (0x1 << i)) { |
chris | 0:498b9b4a7bb9 | 56 | _rmw(i,PCA9532_MODE_SET); |
chris | 0:498b9b4a7bb9 | 57 | } |
chris | 0:498b9b4a7bb9 | 58 | } |
chris | 0:498b9b4a7bb9 | 59 | } |
chris | 0:498b9b4a7bb9 | 60 | |
chris | 0:498b9b4a7bb9 | 61 | |
chris | 0:498b9b4a7bb9 | 62 | void PCA9532::clear (int leds) { |
chris | 0:498b9b4a7bb9 | 63 | for (int i=0; i < 16; i++) { |
chris | 0:498b9b4a7bb9 | 64 | if (leds & (0x1 << i)) { |
chris | 0:498b9b4a7bb9 | 65 | _rmw(i,PCA9532_MODE_CLEAR); |
chris | 0:498b9b4a7bb9 | 66 | } |
chris | 0:498b9b4a7bb9 | 67 | } |
chris | 0:498b9b4a7bb9 | 68 | } |
chris | 0:498b9b4a7bb9 | 69 | |
chris | 0:498b9b4a7bb9 | 70 | |
chris | 0:498b9b4a7bb9 | 71 | void PCA9532::pwm0 (int leds) { |
chris | 0:498b9b4a7bb9 | 72 | for (int i=0; i < 16; i++) { |
chris | 0:498b9b4a7bb9 | 73 | if (leds & (0x1 << i)) { |
chris | 0:498b9b4a7bb9 | 74 | _rmw(i,PCA9532_MODE_PWM0); |
chris | 0:498b9b4a7bb9 | 75 | } |
chris | 0:498b9b4a7bb9 | 76 | } |
chris | 0:498b9b4a7bb9 | 77 | } |
chris | 0:498b9b4a7bb9 | 78 | |
chris | 0:498b9b4a7bb9 | 79 | |
chris | 0:498b9b4a7bb9 | 80 | void PCA9532::pwm1 (int leds) { |
chris | 0:498b9b4a7bb9 | 81 | for (int i=0; i < 16; i++) { |
chris | 0:498b9b4a7bb9 | 82 | if (leds & (0x1 << i)) { |
chris | 0:498b9b4a7bb9 | 83 | _rmw(i,PCA9532_MODE_PWM1); |
chris | 0:498b9b4a7bb9 | 84 | } |
chris | 0:498b9b4a7bb9 | 85 | } |
chris | 0:498b9b4a7bb9 | 86 | } |
chris | 0:498b9b4a7bb9 | 87 | |
chris | 0:498b9b4a7bb9 | 88 | |
chris | 0:498b9b4a7bb9 | 89 | void PCA9532::duty0 (float d) { |
chris | 0:498b9b4a7bb9 | 90 | |
chris | 0:498b9b4a7bb9 | 91 | char duty = 0; |
chris | 0:498b9b4a7bb9 | 92 | |
chris | 0:498b9b4a7bb9 | 93 | if (d > 1.0) { duty = 255; } |
chris | 0:498b9b4a7bb9 | 94 | else if ( d < 0.0 ) { duty = 0; } |
chris | 0:498b9b4a7bb9 | 95 | else { duty = 256 * d; } |
chris | 0:498b9b4a7bb9 | 96 | |
chris | 0:498b9b4a7bb9 | 97 | _write(PCA9532_REG_PWM0,duty); |
chris | 0:498b9b4a7bb9 | 98 | |
chris | 0:498b9b4a7bb9 | 99 | } |
chris | 0:498b9b4a7bb9 | 100 | |
chris | 0:498b9b4a7bb9 | 101 | |
chris | 0:498b9b4a7bb9 | 102 | void PCA9532::duty1 (float d) { |
chris | 0:498b9b4a7bb9 | 103 | |
chris | 0:498b9b4a7bb9 | 104 | char duty = 0; |
chris | 0:498b9b4a7bb9 | 105 | |
chris | 0:498b9b4a7bb9 | 106 | if (d > 1.0) { duty = 255; } |
chris | 0:498b9b4a7bb9 | 107 | else if ( d < 0.0 ) { duty = 0; } |
chris | 0:498b9b4a7bb9 | 108 | else { duty = 256 * d; } |
chris | 0:498b9b4a7bb9 | 109 | |
chris | 0:498b9b4a7bb9 | 110 | _write(PCA9532_REG_PWM1,duty); |
chris | 0:498b9b4a7bb9 | 111 | |
chris | 0:498b9b4a7bb9 | 112 | } |
chris | 0:498b9b4a7bb9 | 113 | |
chris | 0:498b9b4a7bb9 | 114 | |
chris | 0:498b9b4a7bb9 | 115 | |
chris | 0:498b9b4a7bb9 | 116 | |
chris | 0:498b9b4a7bb9 | 117 | |
chris | 0:498b9b4a7bb9 | 118 | |
chris | 0:498b9b4a7bb9 | 119 | |
chris | 0:498b9b4a7bb9 | 120 | /* |
chris | 0:498b9b4a7bb9 | 121 | led is in the range 0-15 |
chris | 0:498b9b4a7bb9 | 122 | mode is inthe range 0-3 |
chris | 0:498b9b4a7bb9 | 123 | */ |
chris | 0:498b9b4a7bb9 | 124 | |
chris | 0:498b9b4a7bb9 | 125 | void PCA9532::_rmw(int led, int mode) { |
chris | 0:498b9b4a7bb9 | 126 | |
chris | 0:498b9b4a7bb9 | 127 | int reg = 0; |
chris | 0:498b9b4a7bb9 | 128 | int offset = (led % 4); |
chris | 0:498b9b4a7bb9 | 129 | |
chris | 0:498b9b4a7bb9 | 130 | // makesure mode is within bounds |
chris | 0:498b9b4a7bb9 | 131 | if ( (mode < 0) || (mode > 3) ) { |
chris | 0:498b9b4a7bb9 | 132 | return; |
chris | 0:498b9b4a7bb9 | 133 | } |
chris | 0:498b9b4a7bb9 | 134 | |
chris | 0:498b9b4a7bb9 | 135 | |
chris | 0:498b9b4a7bb9 | 136 | // determine which register this is, |
chris | 0:498b9b4a7bb9 | 137 | if (led < 4) { |
chris | 0:498b9b4a7bb9 | 138 | reg = PCA9532_REG_LS0;} |
chris | 0:498b9b4a7bb9 | 139 | |
chris | 0:498b9b4a7bb9 | 140 | else if ( (led > 3) && (led < 8) ) { |
chris | 0:498b9b4a7bb9 | 141 | reg = PCA9532_REG_LS1;} |
chris | 0:498b9b4a7bb9 | 142 | |
chris | 0:498b9b4a7bb9 | 143 | else if ( (led > 7) && (led < 12) ) { |
chris | 0:498b9b4a7bb9 | 144 | reg = PCA9532_REG_LS2;} |
chris | 0:498b9b4a7bb9 | 145 | |
chris | 0:498b9b4a7bb9 | 146 | else if ( (led > 11) && (led < 16) ) { |
chris | 0:498b9b4a7bb9 | 147 | reg = PCA9532_REG_LS3;} |
chris | 0:498b9b4a7bb9 | 148 | |
chris | 0:498b9b4a7bb9 | 149 | else { return; } |
chris | 0:498b9b4a7bb9 | 150 | |
chris | 0:498b9b4a7bb9 | 151 | // read the current status of the register |
chris | 0:498b9b4a7bb9 | 152 | char regval = _read(reg); |
chris | 0:498b9b4a7bb9 | 153 | |
chris | 0:498b9b4a7bb9 | 154 | // clear the two bit slice at the calculated offset |
chris | 0:498b9b4a7bb9 | 155 | regval &= ~(0x3 << (2 * offset)); |
chris | 0:498b9b4a7bb9 | 156 | |
chris | 0:498b9b4a7bb9 | 157 | // now OR in the mode, shifted by 2 8 offset |
chris | 0:498b9b4a7bb9 | 158 | regval |= (mode << (2 * offset)); |
chris | 0:498b9b4a7bb9 | 159 | |
chris | 0:498b9b4a7bb9 | 160 | // write this back |
chris | 0:498b9b4a7bb9 | 161 | |
chris | 0:498b9b4a7bb9 | 162 | _write(reg,regval); |
chris | 0:498b9b4a7bb9 | 163 | |
chris | 0:498b9b4a7bb9 | 164 | return; |
chris | 0:498b9b4a7bb9 | 165 | } |
chris | 0:498b9b4a7bb9 | 166 | |
chris | 0:498b9b4a7bb9 | 167 | |
chris | 0:498b9b4a7bb9 | 168 | void PCA9532::_write(int reg, int data) { |
chris | 0:498b9b4a7bb9 | 169 | char args[2]; |
chris | 0:498b9b4a7bb9 | 170 | args[0] = reg; |
chris | 0:498b9b4a7bb9 | 171 | args[1] = data; |
chris | 0:498b9b4a7bb9 | 172 | _i2c.write(_addr,args,2); |
chris | 0:498b9b4a7bb9 | 173 | } |
chris | 0:498b9b4a7bb9 | 174 | |
chris | 0:498b9b4a7bb9 | 175 | |
chris | 0:498b9b4a7bb9 | 176 | int PCA9532::_read(int reg) { |
chris | 0:498b9b4a7bb9 | 177 | char args[2]; |
chris | 0:498b9b4a7bb9 | 178 | args[0] = reg; |
chris | 0:498b9b4a7bb9 | 179 | _i2c.write(_addr,args,2); |
chris | 0:498b9b4a7bb9 | 180 | return(args[1]); |
chris | 0:498b9b4a7bb9 | 181 | } |
chris | 0:498b9b4a7bb9 | 182 | |
chris | 0:498b9b4a7bb9 | 183 | |
chris | 0:498b9b4a7bb9 | 184 | |
chris | 0:498b9b4a7bb9 | 185 | |
chris | 0:498b9b4a7bb9 | 186 |