Diff: 24LC64_eeprom.cpp

Revision:

14:acaa1add097b

Parent:

13:ef7a06fa11de

Child:

16:d1e4b9ad3b8b

--- a/24LC64_eeprom.cpp	Sun Sep 29 16:34:37 2019 +0000
+++ b/24LC64_eeprom.cpp	Sat Nov 30 16:34:58 2019 +0000
@@ -6,8 +6,8 @@
     //  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
-const int addr_wr = 0xa0;  //  set bit 0 for read, clear bit 0 for write
+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  {
@@ -47,6 +47,8 @@
 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];
     bool        rd_24LC64  (int start_addr, char * dest, int length)    ;
     bool        wr_24LC64  (int start_addr, char * dest, int length)    ;
@@ -54,6 +56,7 @@
     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
@@ -71,31 +74,44 @@
     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 = 0;
+    errors = i2c_device_count = 0;
     for (int i = 0; i < 36; i++)
         settings[i] = 0;
+    for (int i = 0; i < 12; i++)
+        i2c_device_list[i] = 0;
     i2c.frequency(400000);      //  Speed 400000 max.
-    int last_found = 0, q;      //  Note address bits 3-1 to match addr pins on device
+//    int last_found = 0, q;      //  Note address bits 3-1 to match addr pins on device
+    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:
                 pc.printf   ("I2C device found at 0x%x\r\n", i);
-                last_found = i;
+//                last_found = i;
+                i2c_device_list[i2c_device_count++] = i;
             case    2:      //  Device not seen at this address
             break;
             default:
-                pc.printf   ("Unknown error %d in check_24LC64\r\n", q);
+                pc.printf   ("Unknown error %d from i2c.write while looking for i2c devices\r\n", q);
                 errors |= 512;
             break;
         }
     }
     i2c.stop();
-    if  (errors || last_found != 0xa0)    {
+//    if  (errors || last_found != 0xa0)    {
+    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