Hi,
I do not know if there will be any code over head due to C++.
Unfortunately my forte is 'C'. Can I trouble you for some
examples/sample code please? Thank you once again.
Use a 32-bit unsigned integer and a typedef as it has been suggested and
You're done. It would be foolish to move on to C++ in an existing project.
For fun You can try to translate Your code with avr-g++. It should compile
and library functions seem to work even without declaring them as extern
"C", but may have side effects. Most of the language core is backward
compatible to C.
Many stereotypes exist about the inefficiency of C++ and some of them
contain a grain of truth. Try it Yourself and have a deep look into
Stroustrup's "The C++ programming language", which is worth every cent.
The following code example may look dumb, because it does nothing really
interesting. But the point is: By defining all those operators manually You
gain full control over type conversion and You can not mix up internal and
external addresses. Many operators are missing, so take it as a hint for
further experiments.
// Everything related to address calculation and conversion
class ExtFlashAddr
{
public:
// ExtFlashAddr myAddr = ExtFlashAddr(0x4711)
inline explicit ExtFlashAddr(uint32_t address = 0);
// Copy constructor
inline ExtFlashAddr(const ExtFlashAddr& other);
// ExtFlashAddr myAddr = otherAddr
inline ExtFlashAddr& operator=(const ExtFlashAddr& other);
// myAddr++
inline ExtFlashAddr& operator++();
friend ExtFlashAddr operator+(const ExtFlashAddr&, const ExtFlashAddr&);
private:
uint32_t addr;
};
inline ExtFlashAddr operator+(const ExtFlashAddr& addr1, const ExtFlashAddr&
addr2);
// Access functions
class ExtFlashTools
{
public:
static void read(void* dst, const ExtFlashAddr& src, size_t size);
static void erase(const ExtFlashAddr& src, size_t size);
static void write(const ExtFlashAddr& dst, void const* src, size_t
size);
};
ExtFlashAddr::ExtFlashAddr(uint32_t address)
{
this->addr = address;
}
ExtFlashAddr::ExtFlashAddr(const ExtFlashAddr& other)
{
this->addr = other.addr;
}
ExtFlashAddr& ExtFlashAddr::operator=(const ExtFlashAddr& other)
{
this->addr = other.addr;
return *this;
}
ExtFlashAddr& ExtFlashAddr::operator++()
{
addr++;
return *this;
}
ExtFlashAddr operator+(const ExtFlashAddr& addr1, const ExtFlashAddr& addr2)
{
return ExtFlashAddr(addr1.addr + addr2.addr);
}
The code above should be optimized away with -Os.
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