File content as of revision 17:cc9b854295d6:

#include "mbed.h"
#include "STM3_ESC.h"
#include "BufferedSerial.h"
extern  BufferedSerial pc;
extern  error_handling_Jan_2019     ESC_Error    ;         //  Provides array usable to store error codes.
    //  Code for 24LC64 8k x 8 bit eeprom
    //  Code based on earlier work using memory FM24W256, also at i2c address 0xa0;

const int   addr_rd = 0xa1;  //  set bit 0 for read, clear bit 0 for write 24LC64
const int   addr_wr = 0xa0;  //  set bit 0 for read, clear bit 0 for write 24LC64
const int   ACK     = 1;
/*struct  optpar  {
    int     min, max, de_fault;  //  min, max, default
    const char * txt;     //  description
}   ;
*/
struct  optpar option_list[] = {
    {0, 1, 1,     "MotorA direction [0 or 1]"},       //  MOTADIR
    {0, 1, 0,     "MotorB direction [0 or 1]"},       //  MOTBDIR
    {4, 8, 8,     "MotorA poles 4 or 6 or 8"},      //  MOTAPOLES
    {4, 8, 8,     "MotorB poles 4 or 6 or 8"},      //  MOTBPOLES
    {1, 4, 1,     "MotorA 0R05 shunt Rs 1 to 4"},        //  ISHUNTB
    {1, 4, 1,     "MotorB 0R05 shunt Rs 1 to 4"},        //  ISHUNTB
    {10, 50, 20,  "POT_REGBRAKE_RANGE percentage 10 to 50"},     //  POT_REGBRAKE_RANGE
    {0, 1, 0,     "Servo1 out 0 = Disabled, 1= Output enabled"},        //  SVO1
    {0, 1, 0,     "Servo2 out 0 = Disabled, 1= Output enabled"},        //  SVO2
    {0, 2, 0,     "RC Input1 0 = Not used, 1= Uni_dir, 2= Bi_dir"},     //  RCIN1
    {0, 2, 0,     "RC Input2 0 = Not used, 1= Uni_dir, 2= Bi_dir"},     //  RCIN2
    {2, 6, 2,     "Command source 2= COM2 (Touch Screen), 3= Pot, 4= RCIn1, 5= RCIn2, 6=RCin_both"},     //  COMM_SRC
    {'1', '9', '0',     "Alternative ID ascii '1' to '9'"}, //  BOARD_ID    defaults to '0' before eerom setup for first time
    {10, 250, 60,       "Top speed MPH, range 1.0 to 25.0"},    //  New Jan 2019 TOP_SPEED
    {50, 253, 98,       "Wheel diameter mm"},   //  New 01/06/2018
    {10, 253, 27,       "Motor pinion"},   //  New 01/06/2018
    {50, 253, 85,       "Wheel gear"},   //  New 01/06/2018     ** NOTE this and above two used to calculate RPM to MPH **
    {0, 255, 12,     "RC in 1 trim"},    //  New Dec 2019 RCI1_TRIM read as 2's complement (-128 to +127), user enters -128 to +127
    {0, 255, 12,     "RC in 2 trim"},    //  New Dec 2019 RCI2_TRIM read as 2's complement (-128 to +127), user enters -128 to +127
    {10, 50, 20,     "RCIN_REGBRAKE_RANGE stick range percent 10 to 50"},     //  RCIN_REGBRAKE_RANGE
    {10, 90, 50,     "RCIN_STICK_ATTACK rate percent 10 to 90"},     //  RCIN_STICK_ATTACK
    {0, 1, 0,     "RCIN1 direction swap 0 normal, 1 reverse"},     //  RCIN1REVERSE
    {0, 1, 0,     "RCIN2 direction swap 0 normal, 1 reverse"},     //  RCIN2REVERSE
    {11, 63, 48,    "Nominal system voltage, used to calculate current scaling"},    //   NOM_SYSTEM_VOLTS
    {5, 91, 90,    "Brake Effectiveness percentage"},
    {1, 5, 1,       "Baud rate, [1=9k6, 2=19k2, 3=38k4, 4=78k6, 5=115k2] = "},   //  BAUD 1=9k6, 2=19k2, 3=38k4, 4=78k6, 5=115k2
    {0, 100, 0,     "Future 11"},
    {0, 100, 0,     "Future 12"},
    {0, 100, 0,     "Future 13"},
    {0, 100, 0,     "Future 14"},
    {0, 100, 0,     "Future 15"},
    {0, 100, 0,     "Future 16"},
}   ;

const   int    numof_eeprom_options    = sizeof(option_list) / sizeof (struct optpar);




/*
class   eeprom_settings {
    I2C i2c;
    uint32_t    errors;
    uint32_t    i2c_device_count;
    uint32_t    i2c_device_list[12];    //  max 12 i2c devices
    char        settings    [36];
    double      rpm2mphdbl, user_brake_rangedbl, Vnomdbl;
    bool        rd_24LC64  (uint32_t start_addr, char * dest, uint32_t length)    ;
    bool        wr_24LC64  (uint32_t start_addr, char * dest, uint32_t length)    ;
    bool        set_24LC64_internal_address (int    start_addr) ;
    bool        ack_poll    ()  ;
  public:
    eeprom_settings (PinName sda, PinName scl); //  Constructor
    bool        do_we_have_i2c  (uint32_t x)    ;
    char        rd  (uint32_t)  ;           //  Read one setup char value from private buffer 'settings'
    bool        wr  (char, uint32_t)  ;     //  Write one setup char value to private buffer 'settings'
    bool        save    ()  ;               //  Write 'settings' buffer to EEPROM
    bool        set_defaults    ();         //  Put default settings into EEPROM and local buffer
    uint32_t    errs    ()  ;               //  Return errors
    const char *      t   (uint32_t);
    int         min (uint32_t)   ;
    int         max (uint32_t)   ;
    int         def (uint32_t)   ;
    bool        in_range   (char val, uint32_t p)  ;
    void        edit   (double * dbl, uint32_t numof_dbls)    ;
    double      user_brake_range ()  ;
    double      top_speed ()  ;
    double      rpm2mph ()  ;
    double      rpm2mph (double)  ;
}   ;
*/

uint32_t    eeprom_settings::baud    ()  {
    const   uint32_t    brates[] = {0, 9600, 19200, 38400, 76800, 11520};
    return  brates[settings[BAUD]];
}

double      eeprom_settings::top_speed ()  {
    return  top_speeddbl;
}

double  eeprom_settings::brake_effectiveness    ()  {
    return  brake_eff;
}

double  eeprom_settings::user_brake_range    ()  {
    return  user_brake_rangedbl;
}

double  eeprom_settings::Vnom    ()  {
    return  Vnomdbl;
}

double  eeprom_settings::rpm2mph    ()  {
    return  rpm2mphdbl;
}

double  eeprom_settings::rpm2mph    (double rpm)  {
    return  rpm2mphdbl * rpm;
}

void    eeprom_settings::edit   (double * dbl, uint32_t numof_dbls)    {
extern  void    set_RCIN_offsets    ()  ;
    const char* labs[3] = {"Disabled","Uni_directional","Bi_directional"};
    char    temps[MAX_CLI_PARAMS+1];  //  max num of parameters entered from pc terminal
    uint32_t i;
    double  user_scratch;
    double  topspeed;   //  New Jan 2019 - set max loco speed
    pc.printf   ("\r\nus - User Settings data in EEPROM\r\nSyntax 'us' with no parameters lists current state.\r\n");
    if  (numof_dbls > 0)  {           //  If more than 0 parameters supplied
        if  (numof_dbls > MAX_CLI_PARAMS)
            numof_dbls = MAX_CLI_PARAMS;
        for (i = 0; i < numof_dbls; i++)
            temps[i] = (char)dbl[i];          //  recast doubles to char
        while   (MAX_CLI_PARAMS > i)
            temps[i++] = 0;
        i = temps[0];
        switch  (i) {   //  First number read from user response after "mode"
            case    11:      //  MotorA_dir [0 or 1], MotorB_dir [0 or 1]
                wr(temps[1], MOTADIR);
                wr(temps[2], MOTBDIR);
                break;
            case    12:      //  MotorA_poles [4,6,8], MotorB_poles [4,6,8]
                if  (temps[1] == 4 || temps[1] == 6 || temps[1] == 8)
                    wr(temps[1], MOTAPOLES);
                if  (temps[2] == 4 || temps[2] == 6 || temps[2] == 8)
                    wr(temps[2], MOTBPOLES);
                break;
            case    13:      //  MotorA_ current sense resistors [1 to 4], MotorB_ current sense resistors [1 to 4]
                wr(temps[1], ISHUNTA);     //  Corrected since published
                wr(temps[2], ISHUNTB);
                break;
            case    14:
                wr(temps[1], BRAKE_EFFECTIVENESS);
                break;
            case    15:
                pc.printf   ("POT_REGBRAKE_RANGE value entered = %d\r\n", temps[1]);
                if  (!in_range(temps[1], POT_REGBRAKE_RANGE))
                    temps[1] = def(POT_REGBRAKE_RANGE);
                wr    (temps[1], POT_REGBRAKE_RANGE);
                break;
            case    16:      //  2 Servo1 [0 or 1], Servo2 [0 or 1]
                wr(temps[1], SVO1);
                wr(temps[2], SVO2);
                break;
            case    17:      //  3 RCIn1 [0 or 1], RCIn2 [0 or 1]
                wr(temps[1], RCIN1);
                wr(temps[2], RCIN2);
                break;
            case    18:
                wr(temps[1], RCIN1REVERSE);
                break;
            case    19:
                wr(temps[1], RCIN2REVERSE);
                break;
/*            case    33:      //  Not shown in menu, just to test stuff searching for strtod bug, to be deleted later
                pc.printf   ("Testing to fix strtod bug, ");
                i = 0;
                while   (numof_dbls--)
                    pc.printf   ("%.3f, ", dbl[i++]);
                pc.printf   ("TheEnd\r\n");
                break;*/
            case    21:      //  3 RCIn1 trim [-128 to +127]
            case    22:      //  3 RCIn2 trim [-128 to +127]
                user_scratch = dbl[1];
                if  (user_scratch > 127.0)  user_scratch = 127.0;
                if  (user_scratch < -128.0) user_scratch = -128.0;
                wr    (((signed char) user_scratch), i == 21 ? RCI1_TRIM : RCI2_TRIM);
                set_RCIN_offsets    ()  ;
                break;
            case    23:     //  RCIN_REGBRAKE_RANGE
                wr    (temps[1], RCIN_REGBRAKE_RANGE);
                break;
            case    24:      //  RCIN_STICK_ATTACK
                wr    (temps[1], RCIN_STICK_ATTACK);
                break;
            case    25:      //  4 Board ID '0' to '9'
                if  (temps[1] <= 9)    //  pointless to compare unsigned integer with zero
                    wr('0' | temps[1], BOARD_ID);
                break;
            case    26:      //  TOP_SPEED
                topspeed = dbl[1];
                if  (topspeed > 25.0)   topspeed = 25.0;
                if  (topspeed < 1.0)    topspeed = 1.0;
                wr((char)(topspeed * 10.0), TOP_SPEED);
                break;
            case    27:      //  5 Wheel dia mm, Motor pinion teeth, Wheel gear teeth
                wr(temps[1], WHEELDIA);
                wr(temps[2], MOTPIN);
                wr(temps[3], WHEELGEAR);
                break;
            case    28:      //    {2, 5, 2, "Command source 2= COM2 (Touch Screen), 3= Pot, 4= RC Input1, 5= RC Input2, 6=RC1+2 Robot"},
                if  (temps[1] > 1 && temps[1] <= 6)
                    wr(temps[1], COMM_SRC);
                break;
            case    29: //  Nominal System Voltage
                wr    (temps[1], NOM_SYSTEM_VOLTS);
                break;
            case    83: //  set to defaults
                set_defaults   ();
                break;
            case    30: //  BAUD
                wr  (temps[1], BAUD);
                break;
/*            case    9:      //  9 Save settings
                save   ();
                pc.printf   ("Saving settings to EEPROM\r\n");
                break;*/
            default:
                pc.printf   ("Not found - user setting %d\r\n", i);
                i = 0;
                break;
        }       //  endof   switch
        if  (i) {
            save    ();
            pc.printf   ("Saving settings to EEPROM\r\n");
        }
    }           //  endof   //  If more than 0 parameters supplied
    else    {   //  command was just "mode" on its own
        pc.printf   ("No Changes\r\n");
    }
    pc.printf   ("us 11\t%s = %d, %s = %d\r\n", t(MOTADIR), settings[MOTADIR], t(MOTBDIR), settings[MOTBDIR]);
    pc.printf   ("us 12\t%s = %d, %s = %d\r\n", t(MOTAPOLES), settings[MOTAPOLES], t(MOTBPOLES), settings[MOTBPOLES]);
    pc.printf   ("us 13\tNumof motor current shunt resistors [%d to %d], MotorA = %d, MotorB = %d\r\n", min(ISHUNTA), max(ISHUNTA), settings[ISHUNTA], settings[ISHUNTB]);
    pc.printf   ("us 14\t%s [min %d, max %d] = %d\r\n", t(BRAKE_EFFECTIVENESS), min(BRAKE_EFFECTIVENESS), max(BRAKE_EFFECTIVENESS), settings[BRAKE_EFFECTIVENESS]);
    pc.printf   ("us 15\t%s[%d to %d] = %d\r\n", t(POT_REGBRAKE_RANGE), min(POT_REGBRAKE_RANGE), max(POT_REGBRAKE_RANGE), settings[POT_REGBRAKE_RANGE]);
    pc.printf   ("us 16\tServo1 [0 or 1] = %d %s, Servo2 [0 or 1] = %d %s\r\n", settings[SVO1], settings[SVO1] == 0 ? "Disabled":"Enabled", settings[SVO2], settings[SVO2] == 0 ? "Disabled":"Enabled");
    pc.printf   ("us 17\tRCIn1 [0 disable, 1 Uni_dir, 2 Bi_dir] = %d, %s\r\n\tRCIn2 [0 disable, 1 Uni_dir, 2 Bi_dir] = %d, %s\r\n", settings[RCIN1], labs[settings[RCIN1]], settings[RCIN2], labs[rd(RCIN2)]);
    pc.printf   ("us 18\t%s RCIN1 = %d, %s\r\n", t(RCIN1REVERSE), settings[RCIN1REVERSE], settings[RCIN1REVERSE] == 0 ? "NORMAL":"REVERSE");
    pc.printf   ("us 19\t%s RCIN2 = %d, %s\r\n", t(RCIN2REVERSE), settings[RCIN2REVERSE], settings[RCIN2REVERSE] == 0 ? "NORMAL":"REVERSE");
    pc.printf   ("us 21\tRCIn1 two's comp trim, [-128 to +127] = %d\r\n", (signed char) settings[RCI1_TRIM]);
    pc.printf   ("us 22\tRCIn2 two's comp trim, [-128 to +127] = %d\r\n", (signed char) settings[RCI2_TRIM]);
    pc.printf   ("us 23\tRCIn Regen braking uses this pcntage of movement range, [%d to %d] = %d\r\n",min(RCIN_REGBRAKE_RANGE), max(RCIN_REGBRAKE_RANGE), settings[RCIN_REGBRAKE_RANGE]);
    pc.printf   ("us 24\tRCIn Stick move Attack rate, [%d to %d] = %d\r\n",min(RCIN_STICK_ATTACK), max(RCIN_STICK_ATTACK), settings[RCIN_STICK_ATTACK]);
    pc.printf   ("us 25\tBoard ID ['0' to '9'] = '%c'\r\n", settings[BOARD_ID]);
    pc.printf   ("us 26\t%s = %.1f\r\n", t(TOP_SPEED), double(settings[TOP_SPEED]) / 10.0);
//                  WHEELDIA, MOTPIN, WHEELGEAR, used in converting RPM to MPH
    pc.printf   ("us 27\t%s = %d, %s = %d, %s = %d\r\n", t(WHEELDIA), settings[WHEELDIA], t(MOTPIN), settings[MOTPIN], t(WHEELGEAR), settings[WHEELGEAR]);
    pc.printf   ("us 28\tCommand Src [%d] - 2=COM2 (Touch Screen), 3=Pot, 4=RC In1, 5=RC In2, 6=RC1+2\r\n", settings[COMM_SRC]);
    pc.printf   ("us 29\t%s = %d\r\n", t(NOM_SYSTEM_VOLTS), settings[NOM_SYSTEM_VOLTS]);
    pc.printf   ("us 30\t%s %d\r\n", t(BAUD), settings[BAUD]);
    pc.printf   ("us 83\tSet to defaults\r\n");
//    pc.printf   ("us 9\tSave settings\r\r\n");
}

bool    eeprom_settings::in_range   (char val, uint32_t p)  {
    if  ((val >= option_list[p].min) && (val <= option_list[p].max))
        return  true;
    return  false;
}
uint32_t    eeprom_settings::min (uint32_t i)    {
    if  (i >= numof_eeprom_options)
        i = numof_eeprom_options - 1;
    return  option_list[i].min;
}
uint32_t    eeprom_settings::max (uint32_t i)    {
    if  (i >= numof_eeprom_options)
        i = numof_eeprom_options - 1;
    return  option_list[i].max;
}
uint32_t    eeprom_settings::def (uint32_t i)    {
    if  (i >= numof_eeprom_options)
        i = numof_eeprom_options - 1;
    return  option_list[i].de_fault;
}

const char *  eeprom_settings::t  (uint32_t    i)  {
    if  (i >= numof_eeprom_options)
        i = numof_eeprom_options - 1;
    return  option_list[i].txt;
}

bool        eeprom_settings::set_defaults    () {         //  Put default settings into EEPROM and local buffer
    for (int i = 0; i < numof_eeprom_options; i++)
        settings[i] = option_list[i].de_fault;       //  Load defaults and 'Save Settings'
    return  save    ();
}

uint32_t    eeprom_settings::errs   ()  {
    return  errors;
}

bool    eeprom_settings::do_we_have_i2c  (uint32_t x)    {
    for (int i = 0; i < i2c_device_count; i++)  {
        if  (i2c_device_list[i] == x)
            return  true;
    }
    return  false;
}

//  Use :   eeprom_settings (SDA_PIN, SCL_PIN);
eeprom_settings::eeprom_settings    (PinName sda, PinName scl) : i2c(sda, scl)  //  Constructor
{
    errors = i2c_device_count = 0;
    for (int i = 0; i < 36; i++)
        settings[i] = 0;
    for (int i = 0; i < MAX_I2C_DEVICES; i++)
        i2c_device_list[i] = 0;
    i2c.frequency(400000);      //  Speed 400000 max.
    int q;
    for (int i = 0; i < 255; i += 2)    {   //  Search for devices at all possible i2c addresses
        i2c.start();
        q = i2c.write(i);   //  may return error code 2 when no start issued
        switch  (q) {
            case    ACK:
                i2c_device_list[i2c_device_count++] = i;
                if  (i2c_device_count >= MAX_I2C_DEVICES)   {
                    i = 300;    //  break out
                    pc.printf   ("Too many i2c devices %d\r\n", i2c_device_count);
                }
            case    2:      //  Device not seen at this address
            break;
            default:
                pc.printf   ("Unknown error %d from i2c.write while looking for i2c devices\r\n", q);
                errors |= 512;
            break;
        }
    }
    i2c.stop();
    if  (errors || !do_we_have_i2c(0xa0))    {
        pc.printf   ("Error - EEPROM not seen %d\r\n", errors);
        errors |= 0xa0;
        ESC_Error.set   (FAULT_EEPROM, errors);                      //  Set FAULT_EEPROM bits if 24LC64 problem
    }
    else    {   //  Found 24LC64 memory on I2C. Attempt to load settings from EEPROM
        errors = 0;
        if  (!rd_24LC64   (0, settings, 32))
            ESC_Error.set   (FAULT_EEPROM, 2);                      //  Set FAULT_EEPROM bit 1 if 24LC64 problem
        for (int i = 0; i < numof_eeprom_options; i++) {
            if  ((settings[i] < option_list[i].min) || (settings[i] > option_list[i].max))  {
                pc.printf   ("EEROM error with %s\r\n", option_list[i].txt);
                settings[i] = option_list[i].de_fault;       //  Load default for faulty entry
                errors++;
            }
        }
    }
    ESC_Error.set   (FAULT_EEPROM, errors);  //  sets nothing if 0
//    if  (errors > 1) {    ??why > 1 ?
    if  (errors > 0) {
//        pc.printf   ("Bad settings found at startup. Restoring defaults\r\n");
//        for (int i = 0; i < numof_eeprom_options2; i++)
//            settings[i] = option_list[i].de_fault;       //  Load defaults and 'Save Settings'
        if  (!wr_24LC64  (0, settings, 32))         //  Save settings
            pc.printf   ("Error saving EEPROM in user_settings19\r\n");
    }
    rpm2mphdbl = 60.0                                                          //  to Motor Revs per hour;
              * ((double)settings[MOTPIN] / (double)settings[WHEELGEAR])  //  Wheel revs per hour
              * PI * ((double)settings[WHEELDIA] / 1000.0)                  //  metres per hour
              * 39.37 / (1760.0 * 36.0);                                      //  miles per hour
    update_dbls ();
//    else    //  0 or 1 error max found
//        pc.printf   ("At startup, settings errors = %d\r\n", errors);
}       //  endof constructor
    
void    eeprom_settings::update_dbls ()  {
    user_brake_rangedbl = (double)settings[POT_REGBRAKE_RANGE] / 100.0;
    Vnomdbl = (double)settings[NOM_SYSTEM_VOLTS];
    brake_eff = (double)settings[BRAKE_EFFECTIVENESS] / 100.0;
    top_speeddbl = (double)settings[TOP_SPEED] / 10.0;
}

bool    eeprom_settings::ack_poll    ()  {   //  wait short while for any previous memory operation to complete
    const int poll_tries    = 40;
    int poll_count = 0;
    bool    i2cfree = false;
    while   (poll_count++ < poll_tries && !i2cfree)  {
        i2c.start   ();
        if  (i2c.write(addr_wr) == ACK)
            i2cfree = true;
        else
            wait_us   (1000);   //  June 2020 changed from wait_ms as now deprecated
    }
    return  i2cfree;
}

bool    eeprom_settings::set_24LC64_internal_address (int    start_addr)   {
    if  (!ack_poll())
    {
        pc.printf   ("Err in set_24LC64_internal_address, no ACK writing device address byte\r\n");
        i2c.stop();
        return  false;
    }
    int err = 0;
    if  (i2c.write(start_addr >> 8)   != ACK) err++;
    if  (i2c.write(start_addr & 0xff) != ACK) err++;
    if  (err)   {
        pc.printf   ("In set_24LC64_internal_address, Believe Device present, failed in writing 2 mem addr bytes %d\r\n", err);
        i2c.stop();
        return  false;
    }
    return  true;
}

bool eeprom_settings::rd_24LC64  (uint32_t start_addr, char * dest, uint32_t length)   {
    int acknak = ACK;
    if(length < 1)
        return false;
    if  (!set_24LC64_internal_address   (start_addr))   {
        pc.printf   ("In rd_24LC64, failed to set_ramaddr\r\n");
        return  false;
    }
    i2c.start();
    if  (i2c.write(addr_rd) != ACK) {
        pc.printf   ("Errors in rd_24LC64 sending addr_rd\r\n");
        return  false;
    }
    while(length--) {
        if(length == 0)
            acknak = 0;
        *dest++ = i2c.read(acknak);
    }
    i2c.stop();
    return  true;
}

bool    eeprom_settings::wr_24LC64  (uint32_t start_addr, char * source, uint32_t length)   {
    int err = 0;
    if(length < 1 || length > 32)   {
        pc.printf   ("Length out of range %d in wr_24LC64\r\n", length);
        return  false;
    }
    ack_poll    ();
    if  (!set_24LC64_internal_address   (start_addr))   {
        pc.printf   ("In wr_24LC64, Believe Device present, failed in writing 2 mem addr bytes %d\r\n", err);
        return  false;
    }
    while(length--)
        err += ACK - i2c.write(*source++);
    i2c.stop();
    if  (err)   {
        pc.printf   ("in wr_24LC64, device thought good, mem addr write worked, failed writing string\r\n");
        return  false;
    }
//    pc.printf   ("In wr_24LC64 No Errors Found!\r\n");
    return  true;
}

char    eeprom_settings::rd  (uint32_t i)  {           //  Read one setup char value from private buffer 'settings'
    if  (i > 31)    {
        pc.printf   ("ERROR Attempt to read setting %d\r\n", i);
        return  0;
    }
    return  settings[i];
}

/*
bool    eeprom_settings::in_range   (char val, uint32_t p)  {
    if  ((val >= option_list[p].min) && (val <= option_list[p].max))
        return  true;
    return  false;
}
*/
bool    eeprom_settings::wr  (char val, uint32_t p)  {           //  Write one setup char value to private buffer 'settings'
    if  (p > 31)
        return  false;
    if  ((val >= min(p)) && (val <= max(p)))    {
        settings[p] = val;
        return  true;
    }
    settings[p] = def(p);
//    pc.printf   ("Wrong in wr, %s\r\n", t(p));
    return  false;
}

bool    eeprom_settings::save    ()  {               //  Write 'settings' buffer to EEPROM
    update_dbls ();
    return  wr_24LC64   (0, settings, 32);
}