Viktor Zhezher / Mbed 2 deprecated SI570_VFO_F746NG

Library to control Silicon Labs SI570 10 MHZ TO 1.4 GHZ I2C PROGRAMMABLE XO/VCXO.

Dependencies:   mbed

Fork of SI570 by Gerrit Polder

SI570.cpp@0:dae1bf95c49e, 2010-11-09 (annotated)

Committer:
soldeerridder
Date:
Tue Nov 09 20:56:52 2010 +0000
Revision:
0:dae1bf95c49e
added documentation

Who changed what in which revision?

UserRevisionLine numberNew contents of line
soldeerridder 0:dae1bf95c49e 1 /* mbed SI570 Library, for driving the SI570 programable VCXO
soldeerridder 0:dae1bf95c49e 2 * Copyright (c) 2010, Gerrit Polder, PA3BYA
soldeerridder 0:dae1bf95c49e 3 *
soldeerridder 0:dae1bf95c49e 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
soldeerridder 0:dae1bf95c49e 5 * of this software and associated documentation files (the "Software"), to deal
soldeerridder 0:dae1bf95c49e 6 * in the Software without restriction, including without limitation the rights
soldeerridder 0:dae1bf95c49e 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
soldeerridder 0:dae1bf95c49e 8 * copies of the Software, and to permit persons to whom the Software is
soldeerridder 0:dae1bf95c49e 9 * furnished to do so, subject to the following conditions:
soldeerridder 0:dae1bf95c49e 10 *
soldeerridder 0:dae1bf95c49e 11 * The above copyright notice and this permission notice shall be included in
soldeerridder 0:dae1bf95c49e 12 * all copies or substantial portions of the Software.
soldeerridder 0:dae1bf95c49e 13 *
soldeerridder 0:dae1bf95c49e 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
soldeerridder 0:dae1bf95c49e 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
soldeerridder 0:dae1bf95c49e 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
soldeerridder 0:dae1bf95c49e 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
soldeerridder 0:dae1bf95c49e 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
soldeerridder 0:dae1bf95c49e 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
soldeerridder 0:dae1bf95c49e 20 * THE SOFTWARE.
soldeerridder 0:dae1bf95c49e 21 */
soldeerridder 0:dae1bf95c49e 22
soldeerridder 0:dae1bf95c49e 23 #include "SI570.h"
soldeerridder 0:dae1bf95c49e 24 #include "mbed.h"
soldeerridder 0:dae1bf95c49e 25
soldeerridder 0:dae1bf95c49e 26 SI570::SI570(PinName sda, PinName scl, int address)
soldeerridder 0:dae1bf95c49e 27 : _i2c(sda, scl) {
soldeerridder 0:dae1bf95c49e 28 _address = address;
soldeerridder 0:dae1bf95c49e 29 si570reset();
soldeerridder 0:dae1bf95c49e 30 }
soldeerridder 0:dae1bf95c49e 31
soldeerridder 0:dae1bf95c49e 32
soldeerridder 0:dae1bf95c49e 33
soldeerridder 0:dae1bf95c49e 34 void SI570::si570reset(void) {
soldeerridder 0:dae1bf95c49e 35 _i2c.frequency(100000);
soldeerridder 0:dae1bf95c49e 36
soldeerridder 0:dae1bf95c49e 37 cmd[0] = 135; // reset
soldeerridder 0:dae1bf95c49e 38 cmd[1] = 0x01; //
soldeerridder 0:dae1bf95c49e 39 _i2c.write(_address, cmd, 2); // Send command string
soldeerridder 0:dae1bf95c49e 40
soldeerridder 0:dae1bf95c49e 41 get_registers();
soldeerridder 0:dae1bf95c49e 42 fxtal_device = (FOUT_START_UP * n1 * hsdiv) / rfreq; //MHz
soldeerridder 0:dae1bf95c49e 43
soldeerridder 0:dae1bf95c49e 44 currentFreq = FOUT_START_UP;
soldeerridder 0:dae1bf95c49e 45 }
soldeerridder 0:dae1bf95c49e 46
soldeerridder 0:dae1bf95c49e 47 void SI570::get_registers() {
soldeerridder 0:dae1bf95c49e 48
soldeerridder 0:dae1bf95c49e 49 // Set pointer to location 7 (first echo)
soldeerridder 0:dae1bf95c49e 50 cmd[0] = 0x7;
soldeerridder 0:dae1bf95c49e 51 _i2c.write(_address, cmd, 1);
soldeerridder 0:dae1bf95c49e 52
soldeerridder 0:dae1bf95c49e 53 _i2c.read(_address, buf, 6); // read the six-byte result
soldeerridder 0:dae1bf95c49e 54
soldeerridder 0:dae1bf95c49e 55 // HS_DIV conversion
soldeerridder 0:dae1bf95c49e 56 hsdiv = ((buf[0] & 0xE0) >> 5) + 4; // get reg 7 bits 5, 6, 7
soldeerridder 0:dae1bf95c49e 57 // hsdiv's value could be verified here to ensure that it is one
soldeerridder 0:dae1bf95c49e 58 // of the valid HS_DIV values from the datasheet.
soldeerridder 0:dae1bf95c49e 59 // n1 conversion
soldeerridder 0:dae1bf95c49e 60 n1 = (( buf[0] & 0x1F ) << 2 ) + // get reg 7 bits 0 to 4
soldeerridder 0:dae1bf95c49e 61 (( buf[1] & 0xC0 ) >> 6 ); // add with reg 8 bits 7 and 8
soldeerridder 0:dae1bf95c49e 62 if (n1 == 0) {
soldeerridder 0:dae1bf95c49e 63 n1 = 1;
soldeerridder 0:dae1bf95c49e 64 } else if (n1 & 1 != 0) {
soldeerridder 0:dae1bf95c49e 65 // add one to an odd number
soldeerridder 0:dae1bf95c49e 66 n1 = n1 + 1;
soldeerridder 0:dae1bf95c49e 67 }
soldeerridder 0:dae1bf95c49e 68
soldeerridder 0:dae1bf95c49e 69 frac_bits = (( buf[2] & 0xF ) * POW_2_24 );
soldeerridder 0:dae1bf95c49e 70 frac_bits = frac_bits + (buf[3] * POW_2_16);
soldeerridder 0:dae1bf95c49e 71 frac_bits = frac_bits + (buf[4] * 256);
soldeerridder 0:dae1bf95c49e 72 frac_bits = frac_bits + buf[5];
soldeerridder 0:dae1bf95c49e 73
soldeerridder 0:dae1bf95c49e 74 rfreq = frac_bits;
soldeerridder 0:dae1bf95c49e 75 rfreq = rfreq / POW_2_28;
soldeerridder 0:dae1bf95c49e 76 rfreq = rfreq + ( (( buf[1] & 0x3F ) << 4 ) + (( buf[2] & 0xF0 ) >> 4 ) );
soldeerridder 0:dae1bf95c49e 77 }
soldeerridder 0:dae1bf95c49e 78
soldeerridder 0:dae1bf95c49e 79
soldeerridder 0:dae1bf95c49e 80 double SI570::get_frequency(void) {
soldeerridder 0:dae1bf95c49e 81 get_registers();
soldeerridder 0:dae1bf95c49e 82 return (rfreq*fxtal_device)/(hsdiv*n1);
soldeerridder 0:dae1bf95c49e 83 }
soldeerridder 0:dae1bf95c49e 84
soldeerridder 0:dae1bf95c49e 85 double SI570::get_rfreq(void) {
soldeerridder 0:dae1bf95c49e 86 get_registers();
soldeerridder 0:dae1bf95c49e 87 return rfreq;
soldeerridder 0:dae1bf95c49e 88 }
soldeerridder 0:dae1bf95c49e 89
soldeerridder 0:dae1bf95c49e 90 int SI570::get_n1(void) {
soldeerridder 0:dae1bf95c49e 91 get_registers();
soldeerridder 0:dae1bf95c49e 92 return n1;
soldeerridder 0:dae1bf95c49e 93 }
soldeerridder 0:dae1bf95c49e 94
soldeerridder 0:dae1bf95c49e 95 int SI570::get_hsdiv(void) {
soldeerridder 0:dae1bf95c49e 96 get_registers();
soldeerridder 0:dae1bf95c49e 97 return hsdiv;
soldeerridder 0:dae1bf95c49e 98 }
soldeerridder 0:dae1bf95c49e 99
soldeerridder 0:dae1bf95c49e 100 int SI570::set_frequency(double frequency) {
soldeerridder 0:dae1bf95c49e 101 int err;
soldeerridder 0:dae1bf95c49e 102 float diff = 1000000 * (abs(frequency - currentFreq) / currentFreq);
soldeerridder 0:dae1bf95c49e 103 if (diff < PPM) {
soldeerridder 0:dae1bf95c49e 104 err = set_frequency_small_change(frequency);
soldeerridder 0:dae1bf95c49e 105 } else {
soldeerridder 0:dae1bf95c49e 106 err = set_frequency_large_change(frequency);
soldeerridder 0:dae1bf95c49e 107 }
soldeerridder 0:dae1bf95c49e 108 return err;
soldeerridder 0:dae1bf95c49e 109 }
soldeerridder 0:dae1bf95c49e 110
soldeerridder 0:dae1bf95c49e 111 int SI570::set_frequency_small_change(double frequency) {
soldeerridder 0:dae1bf95c49e 112 unsigned char reg135;
soldeerridder 0:dae1bf95c49e 113 unsigned int whole;
soldeerridder 0:dae1bf95c49e 114 unsigned char counter;
soldeerridder 0:dae1bf95c49e 115 int i;
soldeerridder 0:dae1bf95c49e 116 char reg[6];
soldeerridder 0:dae1bf95c49e 117
soldeerridder 0:dae1bf95c49e 118 rfreq = currentRfreq * frequency / currentFreq;
soldeerridder 0:dae1bf95c49e 119
soldeerridder 0:dae1bf95c49e 120 cmd[0] = 0x8;
soldeerridder 0:dae1bf95c49e 121 _i2c.write(_address, cmd, 1);
soldeerridder 0:dae1bf95c49e 122 _i2c.read(_address, buf, 1); // read register 0x8
soldeerridder 0:dae1bf95c49e 123 reg[1] = buf[0];
soldeerridder 0:dae1bf95c49e 124 reg[2] = 0;
soldeerridder 0:dae1bf95c49e 125
soldeerridder 0:dae1bf95c49e 126 // convert new RFREQ to the binary representation
soldeerridder 0:dae1bf95c49e 127 // separate the integer part
soldeerridder 0:dae1bf95c49e 128 whole = floor(rfreq);
soldeerridder 0:dae1bf95c49e 129 // get the binary representation of the fractional part
soldeerridder 0:dae1bf95c49e 130 frac_bits = floor((rfreq - whole) * POW_2_28);
soldeerridder 0:dae1bf95c49e 131 // set reg 12 to 10 making frac_bits smaller by
soldeerridder 0:dae1bf95c49e 132 // shifting off the last 8 bits everytime
soldeerridder 0:dae1bf95c49e 133 for (counter=5; counter >=3; counter--) {
soldeerridder 0:dae1bf95c49e 134 reg[counter] = frac_bits & 0xFF;
soldeerridder 0:dae1bf95c49e 135 frac_bits = frac_bits >> 8;
soldeerridder 0:dae1bf95c49e 136 }
soldeerridder 0:dae1bf95c49e 137 // set the last 4 bits of the fractional portion in reg 9
soldeerridder 0:dae1bf95c49e 138 reg[2] = SetBits(reg[2], 0xF0, (frac_bits & 0xF));
soldeerridder 0:dae1bf95c49e 139 // set the integer portion of RFREQ across reg 8 and 9
soldeerridder 0:dae1bf95c49e 140 reg[2] = SetBits(reg[2], 0x0F, (whole & 0xF) << 4);
soldeerridder 0:dae1bf95c49e 141 reg[1] = SetBits(reg[1], 0xC0, (whole >> 4) & 0x3F);
soldeerridder 0:dae1bf95c49e 142
soldeerridder 0:dae1bf95c49e 143 // Load the new frequency
soldeerridder 0:dae1bf95c49e 144 // get the current state of register 137
soldeerridder 0:dae1bf95c49e 145 buf[0]=135;
soldeerridder 0:dae1bf95c49e 146 _i2c.write(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 147 _i2c.read(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 148 reg135 = buf[0];
soldeerridder 0:dae1bf95c49e 149
soldeerridder 0:dae1bf95c49e 150 // set the Freeze M bit in that register
soldeerridder 0:dae1bf95c49e 151 buf[0]=135;
soldeerridder 0:dae1bf95c49e 152 buf[1]=reg135 | 0x20;
soldeerridder 0:dae1bf95c49e 153 _i2c.write(_address, buf, 2);
soldeerridder 0:dae1bf95c49e 154
soldeerridder 0:dae1bf95c49e 155 // load the new values into the device at registers 8 to 12;
soldeerridder 0:dae1bf95c49e 156 buf[0]=8;
soldeerridder 0:dae1bf95c49e 157 for (i=1;i<6;i++) {
soldeerridder 0:dae1bf95c49e 158 buf[i]=reg[i];
soldeerridder 0:dae1bf95c49e 159 }
soldeerridder 0:dae1bf95c49e 160 _i2c.write(_address, buf, 6);
soldeerridder 0:dae1bf95c49e 161
soldeerridder 0:dae1bf95c49e 162 // get the current state of register 135
soldeerridder 0:dae1bf95c49e 163 buf[0]=135;
soldeerridder 0:dae1bf95c49e 164 _i2c.write(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 165 _i2c.read(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 166 reg135 = buf[0];
soldeerridder 0:dae1bf95c49e 167 // clear the M bit in that register
soldeerridder 0:dae1bf95c49e 168 buf[0]=135;
soldeerridder 0:dae1bf95c49e 169 buf[1]= reg135 & 0xDF;
soldeerridder 0:dae1bf95c49e 170 _i2c.write(_address, buf, 2);
soldeerridder 0:dae1bf95c49e 171
soldeerridder 0:dae1bf95c49e 172 return 0;
soldeerridder 0:dae1bf95c49e 173 }
soldeerridder 0:dae1bf95c49e 174
soldeerridder 0:dae1bf95c49e 175
soldeerridder 0:dae1bf95c49e 176
soldeerridder 0:dae1bf95c49e 177 int SI570::set_frequency_large_change(double frequency) {
soldeerridder 0:dae1bf95c49e 178 const unsigned char HS_DIV[6] = {11, 9, 7, 6, 5, 4};
soldeerridder 0:dae1bf95c49e 179 int i;
soldeerridder 0:dae1bf95c49e 180 // float ratio = 0;
soldeerridder 0:dae1bf95c49e 181 unsigned char counter;
soldeerridder 0:dae1bf95c49e 182 unsigned char reg137;
soldeerridder 0:dae1bf95c49e 183 char buf[7];
soldeerridder 0:dae1bf95c49e 184 char reg[6];
soldeerridder 0:dae1bf95c49e 185 unsigned int divider_max;
soldeerridder 0:dae1bf95c49e 186 unsigned int curr_div;
soldeerridder 0:dae1bf95c49e 187 unsigned int whole;
soldeerridder 0:dae1bf95c49e 188 unsigned char validCombo;
soldeerridder 0:dae1bf95c49e 189 float curr_n1;
soldeerridder 0:dae1bf95c49e 190 float n1_tmp;
soldeerridder 0:dae1bf95c49e 191
soldeerridder 0:dae1bf95c49e 192 // find dividers (get the max and min divider range for the HS_DIV and N1 combo)
soldeerridder 0:dae1bf95c49e 193 divider_max = floor(FDCO_MAX / frequency); //floorf for SDCC
soldeerridder 0:dae1bf95c49e 194 curr_div = ceil(FDCO_MIN / frequency); //ceilf for SDCC
soldeerridder 0:dae1bf95c49e 195 validCombo = 0;
soldeerridder 0:dae1bf95c49e 196 while (curr_div <= divider_max) {
soldeerridder 0:dae1bf95c49e 197 //check all the HS_DIV values with the next curr_div
soldeerridder 0:dae1bf95c49e 198 for (counter=0; counter<6; counter++) {
soldeerridder 0:dae1bf95c49e 199 // get the next possible n1 value
soldeerridder 0:dae1bf95c49e 200 hsdiv = HS_DIV[counter];
soldeerridder 0:dae1bf95c49e 201 curr_n1 = (curr_div * 1.0) / (hsdiv * 1.0);
soldeerridder 0:dae1bf95c49e 202 // determine if curr_n1 is an integer and an even number or one
soldeerridder 0:dae1bf95c49e 203 // then it will be a valid divider option for the new frequency
soldeerridder 0:dae1bf95c49e 204 n1_tmp = floor(curr_n1);
soldeerridder 0:dae1bf95c49e 205 n1_tmp = curr_n1 - n1_tmp;
soldeerridder 0:dae1bf95c49e 206 if (n1_tmp == 0.0) {
soldeerridder 0:dae1bf95c49e 207 //then curr_n1 is an integer
soldeerridder 0:dae1bf95c49e 208 n1 = (unsigned char) curr_n1;
soldeerridder 0:dae1bf95c49e 209 if ( (n1 == 1) || ((n1 & 1) == 0) ) {
soldeerridder 0:dae1bf95c49e 210 // then the calculated N1 is either 1 or an even number
soldeerridder 0:dae1bf95c49e 211 validCombo = 1;
soldeerridder 0:dae1bf95c49e 212 }
soldeerridder 0:dae1bf95c49e 213 }
soldeerridder 0:dae1bf95c49e 214 if (validCombo == 1) break;
soldeerridder 0:dae1bf95c49e 215 }
soldeerridder 0:dae1bf95c49e 216 if (validCombo == 1) break;
soldeerridder 0:dae1bf95c49e 217 //increment curr_div to find the next divider
soldeerridder 0:dae1bf95c49e 218 //since the current one was not valid
soldeerridder 0:dae1bf95c49e 219 curr_div = curr_div + 1;
soldeerridder 0:dae1bf95c49e 220 }
soldeerridder 0:dae1bf95c49e 221
soldeerridder 0:dae1bf95c49e 222 // if(validCombo == 0) at this point then there's an error
soldeerridder 0:dae1bf95c49e 223 // in the calculation. Check if the provided frequencies
soldeerridder 0:dae1bf95c49e 224 // are valid.
soldeerridder 0:dae1bf95c49e 225 if (validCombo == 0)
soldeerridder 0:dae1bf95c49e 226 return -1;
soldeerridder 0:dae1bf95c49e 227
soldeerridder 0:dae1bf95c49e 228 rfreq = (frequency * n1 * hsdiv) / fxtal_device; //using float
soldeerridder 0:dae1bf95c49e 229 for (counter = 0; counter < 6; counter++) {
soldeerridder 0:dae1bf95c49e 230 reg[counter] = 0; //clear registers
soldeerridder 0:dae1bf95c49e 231 }
soldeerridder 0:dae1bf95c49e 232
soldeerridder 0:dae1bf95c49e 233 // new HS_DIV conversion
soldeerridder 0:dae1bf95c49e 234 hsdiv = hsdiv - 4;
soldeerridder 0:dae1bf95c49e 235 //reset this memory
soldeerridder 0:dae1bf95c49e 236 reg[0] = 0;
soldeerridder 0:dae1bf95c49e 237 //set the top 3 bits of reg 13
soldeerridder 0:dae1bf95c49e 238 reg[0] = (hsdiv << 5);
soldeerridder 0:dae1bf95c49e 239 // convert new N1 to the binary representation
soldeerridder 0:dae1bf95c49e 240 if (n1 == 1) n1 = 0;
soldeerridder 0:dae1bf95c49e 241 else if ((n1 & 1) == 0) n1 = n1 - 1; //if n1 is even, subtract one
soldeerridder 0:dae1bf95c49e 242 // set reg 7 bits 0 to 4
soldeerridder 0:dae1bf95c49e 243 reg[0] = SetBits(reg[0], 0xE0, n1 >> 2);
soldeerridder 0:dae1bf95c49e 244 // set reg 8 bits 6 and 7
soldeerridder 0:dae1bf95c49e 245 reg[1] = (n1 & 3) << 6;
soldeerridder 0:dae1bf95c49e 246
soldeerridder 0:dae1bf95c49e 247 // convert new RFREQ to the binary representation
soldeerridder 0:dae1bf95c49e 248 // separate the integer part
soldeerridder 0:dae1bf95c49e 249 whole = floor(rfreq);
soldeerridder 0:dae1bf95c49e 250 // get the binary representation of the fractional part
soldeerridder 0:dae1bf95c49e 251 frac_bits = floor((rfreq - whole) * POW_2_28);
soldeerridder 0:dae1bf95c49e 252 // set reg 12 to 10 making frac_bits smaller by
soldeerridder 0:dae1bf95c49e 253 // shifting off the last 8 bits everytime
soldeerridder 0:dae1bf95c49e 254 for (counter=5; counter >=3; counter--) {
soldeerridder 0:dae1bf95c49e 255 reg[counter] = frac_bits & 0xFF;
soldeerridder 0:dae1bf95c49e 256 frac_bits = frac_bits >> 8;
soldeerridder 0:dae1bf95c49e 257 }
soldeerridder 0:dae1bf95c49e 258 // set the last 4 bits of the fractional portion in reg 9
soldeerridder 0:dae1bf95c49e 259 reg[2] = SetBits(reg[2], 0xF0, (frac_bits & 0xF));
soldeerridder 0:dae1bf95c49e 260 // set the integer portion of RFREQ across reg 8 and 9
soldeerridder 0:dae1bf95c49e 261 reg[2] = SetBits(reg[2], 0x0F, (whole & 0xF) << 4);
soldeerridder 0:dae1bf95c49e 262 reg[1] = SetBits(reg[1], 0xC0, (whole >> 4) & 0x3F);
soldeerridder 0:dae1bf95c49e 263
soldeerridder 0:dae1bf95c49e 264
soldeerridder 0:dae1bf95c49e 265 // Load the new frequency
soldeerridder 0:dae1bf95c49e 266 // get the current state of register 137
soldeerridder 0:dae1bf95c49e 267 buf[0]=137;
soldeerridder 0:dae1bf95c49e 268 _i2c.write(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 269 _i2c.read(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 270 reg137 = buf[0];
soldeerridder 0:dae1bf95c49e 271
soldeerridder 0:dae1bf95c49e 272 // set the Freeze DCO bit in that register
soldeerridder 0:dae1bf95c49e 273 buf[0]=137;
soldeerridder 0:dae1bf95c49e 274 buf[1]=reg137 | 0x10;
soldeerridder 0:dae1bf95c49e 275 _i2c.write(_address, buf, 2);
soldeerridder 0:dae1bf95c49e 276
soldeerridder 0:dae1bf95c49e 277 // load the new values into the device at registers 7 to 12;
soldeerridder 0:dae1bf95c49e 278 buf[0]=7;
soldeerridder 0:dae1bf95c49e 279 for (i=1;i<7;i++) {
soldeerridder 0:dae1bf95c49e 280 buf[i]=reg[i-1];
soldeerridder 0:dae1bf95c49e 281 }
soldeerridder 0:dae1bf95c49e 282 _i2c.write(_address, buf, 7);
soldeerridder 0:dae1bf95c49e 283
soldeerridder 0:dae1bf95c49e 284
soldeerridder 0:dae1bf95c49e 285 // get the current state of register 137
soldeerridder 0:dae1bf95c49e 286 buf[0]=137;
soldeerridder 0:dae1bf95c49e 287 _i2c.write(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 288 _i2c.read(_address, buf, 1);
soldeerridder 0:dae1bf95c49e 289 reg137 = buf[0];
soldeerridder 0:dae1bf95c49e 290 // clear the FZ_DCO bit in that register
soldeerridder 0:dae1bf95c49e 291 buf[0]=137;
soldeerridder 0:dae1bf95c49e 292 buf[1]= reg137 & 0xEF;
soldeerridder 0:dae1bf95c49e 293 _i2c.write(_address, buf, 2);
soldeerridder 0:dae1bf95c49e 294
soldeerridder 0:dae1bf95c49e 295
soldeerridder 0:dae1bf95c49e 296 // set the NewFreq bit, bit will clear itself once the device is ready
soldeerridder 0:dae1bf95c49e 297 buf[0]=135;
soldeerridder 0:dae1bf95c49e 298 buf[1]= 0x40;
soldeerridder 0:dae1bf95c49e 299 _i2c.write(_address, buf, 2);
soldeerridder 0:dae1bf95c49e 300
soldeerridder 0:dae1bf95c49e 301 currentFreq = frequency;
soldeerridder 0:dae1bf95c49e 302 currentRfreq = rfreq;
soldeerridder 0:dae1bf95c49e 303 return 0;
soldeerridder 0:dae1bf95c49e 304 }
soldeerridder 0:dae1bf95c49e 305
soldeerridder 0:dae1bf95c49e 306
soldeerridder 0:dae1bf95c49e 307 unsigned char SI570::SetBits(unsigned char original, unsigned char reset_mask, unsigned char new_val) {
soldeerridder 0:dae1bf95c49e 308 return (( original & reset_mask ) | new_val );
soldeerridder 0:dae1bf95c49e 309 }
soldeerridder 0:dae1bf95c49e 310