Merge pull request #30 from giminotron5/main

Add WP control

Author: nseidle

src/SparkFun_External_EEPROM.cpp

@@ -66,6 +66,24 @@ bool ExternalEEPROM::begin(uint8_t deviceAddress, TwoWire &wirePort)
 
     return true;
 }
+bool ExternalEEPROM::begin(uint8_t deviceAddress, TwoWire &wirePort, uint8_t WP)
+{
+    if(WP != 255)
+    {
+        pinMode(WP, OUTPUT);
+        digitalWrite(WP, HIGH);
+        settings.wpPin = WP;
+    }
+    settings.i2cPort = &wirePort; // Grab which port the user wants us to use
+    settings.deviceAddress = deviceAddress;
+
+    if (isConnected() == false)
+    {
+        return false;
+    }
+
+    return true;
+}
 
 // Erase entire EEPROM
 void ExternalEEPROM::erase(uint8_t toWrite)
@@ -871,6 +889,9 @@ int ExternalEEPROM::write(uint32_t eepromLocation, const uint8_t *dataToWrite, u
         while (isBusy(settings.deviceAddress) == true) // Poll device's original address, not the modified one
             delayMicroseconds(100); // This shortens the amount of time waiting between writes but hammers the I2C bus
 
+        // Check if we are using Write Protection then disable WP for write access
+        if(settings.wpPin != 255 ) digitalWrite(settings.wpPin, LOW);
+
         settings.i2cPort->beginTransmission(i2cAddress);
         if (settings.addressSize_bytes > 1) // Device larger than 16,384 bits have two byte addresses
             settings.i2cPort->write((uint8_t)((eepromLocation + recorded) >> 8)); // MSB
@@ -888,6 +909,9 @@ int ExternalEEPROM::write(uint32_t eepromLocation, const uint8_t *dataToWrite, u
 
         if (settings.pollForWriteComplete == false)
             delay(settings.writeTime_ms); // Delay the amount of time to record a page
+
+        // Enable Write Protection if we are using WP
+        if(settings.wpPin != 255) digitalWrite(settings.wpPin, HIGH);
     }
 
     return (result);

src/SparkFun_External_EEPROM.h

@@ -111,6 +111,7 @@ struct struct_memorySettings
     uint8_t writeTime_ms;
     bool pollForWriteComplete;
     uint8_t addressSize_bytes;
+    uint8_t wpPin;
 };
 
 class ExternalEEPROM
@@ -122,6 +123,8 @@ class ExternalEEPROM
     int write(uint32_t eepromLocation, const uint8_t *dataToWrite, uint16_t blockSize);
 
     bool begin(uint8_t deviceAddress = 0b1010000, TwoWire &wirePort = Wire); // By default use the Wire port
+    bool begin(uint8_t deviceAddress = 0b1010000, TwoWire &wirePort = Wire, uint8_t WP = 255); // By default use the Wire port
+    
     bool isConnected(uint8_t i2cAddress = 255);
     bool isBusy(uint8_t i2cAddress = 255);
     void erase(uint8_t toWrite = 0x00); // Erase the entire memory. Optional: write a given byte to each spot.
@@ -186,6 +189,7 @@ class ExternalEEPROM
         .writeTime_ms = 5, //All EEPROMs seem to have a max write time of 5ms
         .pollForWriteComplete = true,
         .addressSize_bytes = 2, // Default to two address bytes, to support 24xx32 / 4096 byte EEPROMs and larger
+        .wpPin = 255, // By default, the write protection pin is not set
     };
 };