mbedWSEsbc.h

00001 /* C Library for the WSE-PROJ-SBC
00002  J Bradshaw
00003  20140912
00004  20140918 J Bradshaw - Found CS mistake in Encoder routines
00005     Added comments in Init function, encoder functions
00006  20150210 J Bradshaw - Initialized DigitalOuts with pre-defined logic
00007    levels (CS's high, etc)
00008  20161011 J Bradshaw - Changed MAX1270 ADC SCLK to 5MHz and format(12, 0)
00009    for conversion mode to match datasheet (200ns SCLK max PW high and low)
00010 */
00011 
00012 
00013 // LS7366 ENCODER IC DEFINITIONS
00014 //=============================================================================
00015 // Four commands for the Instruction Register (B7,B6) - LS7366
00016 //=============================================================================
00017 #define CLR     0x00    //Clear Instruction
00018 #define RD      0x01    //Read Instruction
00019 #define WR      0x02    //Write Instruction
00020 #define LOAD    0x03    //Load Instruction
00021 
00022 //=============================================================================
00023 // Register to Select from the Instruction Register (B5,B4,B3) - LS7366
00024 //=============================================================================
00025 #define NONE        0x00    //No Register Selected
00026 #define MDR0        0x01    //Mode Register 0
00027 #define MDR1        0x02    //Mode Register 1
00028 #define DTR         0x03    //Data Transfer Register
00029 #define CNTR        0x04    //Software Configurable Counter Register
00030 #define OTR         0x05    //Output Transfer Register
00031 #define STR         0x06    //Status Register
00032 #define NONE_REG    0x07    //No Register Selected
00033 
00034 // Set-up hardwired IO
00035 SPI spi_max1270(p5, p6, p7);
00036 SPI spi(p5, p6, p7);
00037 DigitalOut max1270_cs(p8, 1);  //CS for MAX1270 ADC (U3)
00038 DigitalOut max522_cs(p11, 1);  //CS for MAX522 DAC (U5)
00039 
00040 DigitalOut ls7166_cs1(p19, 1); //CS for LS7366-1 (U8)
00041 DigitalOut ls7166_cs2(p20, 1); //CS for LS7366-2 (U9)
00042 
00043 DigitalOut mot1_ph1(p21, 0);       
00044 DigitalOut mot1_ph2(p22, 0);
00045 PwmOut mot_en1(p23);
00046 
00047 DigitalOut mot2_ph1(p24, 0);
00048 DigitalOut mot2_ph2(p25, 0);
00049 PwmOut mot_en2(p26);
00050 
00051 DigitalOut led1(LED1, 0);
00052 DigitalOut led2(LED2, 0);
00053 DigitalOut led3(LED3, 0);
00054 DigitalOut led4(LED4, 0);
00055 
00056 Serial pc(USBTX, USBRX); // tx, rx for serial USB interface to pc
00057 Serial xbee(p13, p14); // tx, rx for Xbee
00058 Timer t; // create timer instance
00059 
00060 // ------ Prototypes -----------
00061 int read_max1270(int chan, int range, int bipol);
00062 float read_max1270_volts(int chan, int range, int bipol);
00063 void mot_control(int drv_num, float dc);
00064 void LS7366_cmd(int inst,  int reg);
00065 long LS7366_read_counter(int chan_num);
00066 void LS7366_quad_mode_x4(int chan_num);
00067 void LS7366_reset_counter(int chan_num);
00068 void LS7366_write_DTR(int chan_num,long enc_value);
00069 void write_max522(int chan, float volts);
00070 
00071 //---- Function Listing -------------------------------
00072 int read_max1270(int chan, int range, int bipol){
00073     int cword=0x80;     //set the start bit
00074     
00075     spi_max1270.frequency(5000000); //5MHz Max
00076     spi_max1270.format(8, 0);   // 8 data bits, CPOL0, and CPHA0 (datasheet Digital Interface)
00077         
00078     cword |= (chan << 4);   //shift channel
00079     cword |= (range << 3);
00080     cword |= (bipol << 2);
00081             
00082     max1270_cs = 0;
00083            
00084     spi_max1270.write(cword);
00085     wait_us(15);    //15us    
00086     spi_max1270.format(12, 0);
00087     
00088     int result = spi_max1270.write(0);
00089     
00090     max1270_cs = 1;
00091     spi_max1270.format(8, 0);
00092     return result;
00093 }
00094 
00095 float read_max1270_volts(int chan, int range, int bipol){
00096     float rangevolts=0.0;
00097     float volts=0.0;
00098     int adc_res;
00099 
00100     //read the ADC converter
00101     adc_res = read_max1270(chan, range, bipol) & 0xFFF;
00102         
00103    //Determine the voltage range
00104    if(range)  //RNG bit 
00105      rangevolts=10.0;
00106    else
00107      rangevolts=5.0;
00108              
00109    //bi-polar input range
00110    if(bipol){ //BIP is set, input is +/-
00111      if(adc_res < 0x800){ //if result was positive
00112       volts = ((float)adc_res/0x7FF) * rangevolts;      
00113      }       
00114      else{  //result was negative
00115       volts = -(-((float)adc_res/0x7FF) * rangevolts) - (rangevolts * 2.0); 
00116      }
00117    }
00118    else{  //input is positive polarity only
00119       volts = ((float)adc_res/0xFFF) * rangevolts;   
00120    }
00121    
00122    return volts;     
00123 }
00124     
00125 //Motor control routine for PWM on 5 pin motor driver header
00126 // drv_num is 1 or 2 (defaults to 1, anything but 2)
00127 // dc is signed duty cycle (+/-1.0)
00128 
00129 void mot_control(int drv_num, float dc){        
00130     if(dc>1.0)
00131         dc=1.0;
00132     if(dc<-1.0)
00133         dc=-1.0;
00134     
00135     if(drv_num != 2){           
00136         if(dc > 0.0){
00137             mot1_ph2 = 0;
00138             mot1_ph1 = 1;
00139             mot_en1 = dc;
00140         }
00141         else if(dc < -0.0){
00142             mot1_ph1 = 0;
00143             mot1_ph2 = 1;
00144             mot_en1 = abs(dc);
00145         }
00146         else{
00147             mot1_ph1 = 0;
00148             mot1_ph2 = 0;
00149             mot_en1 = 0.0;
00150         }
00151     }                
00152     else{
00153         if(dc > 0.0){
00154             mot2_ph2 = 0;
00155             mot2_ph1 = 1;
00156             mot_en2 = dc;
00157         }
00158         else if(dc < -0.0){
00159             mot2_ph1 = 0;
00160             mot2_ph2 = 1;
00161             mot_en2 = abs(dc);
00162         }
00163         else{
00164             mot2_ph1 = 0;
00165             mot2_ph2 = 0;
00166             mot_en2 = 0.0;
00167         }
00168     }                   
00169 }
00170 
00171 //----- LS7366 Encoder/Counter Routines --------------------
00172 void LS7366_cmd(int inst,  int reg){
00173     char cmd;
00174     
00175     spi.format(8, 0);
00176     spi.frequency(2000000);
00177     cmd = (inst << 6) | (reg << 3);
00178 //    printf("\r\ncmd=0X%2X", cmd);
00179     spi.write(cmd);
00180 }
00181 
00182 long LS7366_read_counter(int chan_num){
00183     union bytes{
00184         char byte_enc[4];
00185         long long_enc;
00186     }counter;
00187     
00188     counter.long_enc = 0;
00189     
00190     spi.format(8, 0);
00191     spi.frequency(2000000);
00192     
00193     if(chan_num!=2){
00194         ls7166_cs1 = 0;
00195         wait_us(1);
00196         LS7366_cmd(LOAD,OTR);//cmd = 0xe8, LOAD to OTR
00197         ls7166_cs1 = 1;
00198         wait_us(1);
00199         ls7166_cs1 = 0;
00200     }
00201     else{
00202         ls7166_cs2 = 0;    
00203         wait_us(1);
00204         LS7366_cmd(LOAD,OTR);//cmd = 0xe8, LOAD to OTR
00205         ls7166_cs2 = 1;
00206         wait_us(1);
00207         
00208         ls7166_cs2 = 0;        
00209     }
00210     wait_us(1);
00211     LS7366_cmd(RD,CNTR);  //cmd = 0x60, READ from CNTR
00212     counter.byte_enc[3] = spi.write(0x00);
00213     counter.byte_enc[2] = spi.write(0x00);
00214     counter.byte_enc[1] = spi.write(0x00);
00215     counter.byte_enc[0] = spi.write(0x00);
00216     
00217     if(chan_num!=2){
00218         ls7166_cs1 = 1;    
00219     }            
00220     else{
00221         ls7166_cs2 = 1;    
00222     }        
00223     
00224     return counter.long_enc;  //return count
00225 }
00226 
00227 void LS7366_quad_mode_x4(int chan_num){
00228     
00229     spi.format(8, 0);
00230     spi.frequency(2000000);
00231     
00232     if(chan_num!=2){
00233         ls7166_cs1 = 0;    
00234     }            
00235     else{
00236         ls7166_cs2 = 0;    
00237     }    
00238     wait_us(1);
00239     LS7366_cmd(WR,MDR0);// Write to the MDR0 register
00240     wait_us(1);
00241     spi.write(0x03); // X4 quadrature count mode
00242     if(chan_num!=2){
00243         ls7166_cs1 = 1;    
00244     }            
00245     else{
00246         ls7166_cs2 = 1;    
00247     }
00248 }
00249 
00250 void LS7366_reset_counter(int chan_num){    
00251     spi.format(8, 0);           // set up SPI for 8 data bits, mode 0
00252     spi.frequency(2000000);     // 2MHz SPI clock
00253     
00254     if(chan_num!=2){            // activate chip select
00255         ls7166_cs1 = 0;    
00256     }
00257     else{
00258         ls7166_cs2 = 0;    
00259     }    
00260     wait_us(1);                 // short delay
00261     LS7366_cmd(CLR,CNTR);       // Clear the counter register
00262     if(chan_num!=2){            // de-activate chip select
00263         ls7166_cs1 = 1;    
00264     }            
00265     else{
00266         ls7166_cs2 = 1;
00267     }
00268     wait_us(1);                 // short delay
00269     
00270     if(chan_num!=2){            // activate chip select
00271         ls7166_cs1 = 0;    
00272     }            
00273     else{
00274         ls7166_cs2 = 0;    
00275     }        
00276     wait_us(1);                 // short delay
00277     LS7366_cmd(LOAD,CNTR);      // load counter reg
00278     if(chan_num!=2){            // de-activate chip select
00279         ls7166_cs1 = 1;    
00280     }            
00281     else{
00282         ls7166_cs2 = 1;    
00283     }
00284 }
00285 
00286 void LS7366_write_DTR(int chan_num, long enc_value){
00287     union bytes                // Union to speed up byte writes
00288     {
00289         char byte_enc[4];
00290         long long_enc;
00291     }counter;
00292     
00293     spi.format(8, 0);           // set up SPI for 8 data bits, mode 0
00294     spi.frequency(2000000);     // 2MHz SPI clock
00295     
00296     counter.long_enc = enc_value; // pass enc_value to Union
00297     
00298     if(chan_num!=2){              // activate chip select
00299         ls7166_cs1 = 0;    
00300     }            
00301     else{
00302         ls7166_cs2 = 0;    
00303     }   
00304     wait_us(1);                 // short delay
00305     LS7366_cmd(WR,DTR);         // Write to the Data Transfer Register
00306     spi.write(counter.byte_enc[3]); // Write the 32-bit encoder value
00307     spi.write(counter.byte_enc[2]);
00308     spi.write(counter.byte_enc[1]);
00309     spi.write(counter.byte_enc[0]);
00310     if(chan_num!=2){            // de-activate the chip select
00311         ls7166_cs1 = 1;    
00312     }            
00313     else{
00314         ls7166_cs2 = 1;    
00315     }     
00316     
00317     wait_us(1);                 // short delay
00318     if(chan_num!=2){            // activate chip select
00319         ls7166_cs1 = 0;    
00320     }            
00321     else{
00322         ls7166_cs2 = 0;    
00323     }
00324     wait_us(1);                 // short delay
00325     LS7366_cmd(LOAD,CNTR);      // load command to the counter register from DTR
00326     if(chan_num!=2){            // de-activate chip select
00327         ls7166_cs1 = 1;    
00328     }            
00329     else{
00330         ls7166_cs2 = 1;    
00331     }
00332 }   
00333 
00334 //------- MAX522 routines ---------------------------------
00335 void write_max522(int chan, float volts){
00336     int cmd=0x20;   //set UB3
00337     int data_word = (int)((volts/5.0) * 256.0);
00338     if(chan != 2)
00339         cmd |= 0x01;    //set DAC A out
00340     else
00341         cmd |= 0x02;    //set DACB out        
00342     
00343  //   pc.printf("cmd=0x%4X  data_word=0x%4X \r\n", cmd, data_word);
00344     
00345     spi.format(8, 0);
00346     spi.frequency(2000000);
00347     max522_cs = 0;
00348     spi.write(cmd & 0xFF);
00349     spi.write(data_word & 0xFF);
00350     max522_cs = 1;    
00351 }
00352 
00353 void mbedWSEsbcInit(unsigned long pcbaud){
00354     led1 = 0;           //Initialize all LEDs as off
00355     led2 = 0;
00356     led3 = 0;
00357     led4 = 0;
00358     max1270_cs = 1;     //Initialize all chip selects as off
00359     max522_cs = 1;
00360     ls7166_cs1 = 1;
00361     ls7166_cs2 = 1;
00362     
00363     wait(.2);   //delay at beginning for voltage settle purposes
00364     
00365     mot_en1.period_us(50);   //20KHz for DC motor control PWM
00366     pc.baud(pcbaud); //Set up serial port baud rate
00367     pc.printf("\r\n");
00368     xbee.baud(9600);
00369     
00370     LS7366_reset_counter(1);
00371     LS7366_quad_mode_x4(1);       
00372     LS7366_write_DTR(1,0);
00373     
00374     LS7366_reset_counter(2);
00375     LS7366_quad_mode_x4(2);       
00376     LS7366_write_DTR(2,0);
00377           
00378     t.start();  // Set up timer    
00379 }//mbedWSEsbc_init()