NU32v2: A Detailed Look at Programming the PIC32

After you have programmed your PIC32 for the first time and verified that you can create a new project, compile it, and run it on your NU32v2, it is useful to take a step back and understand the basics of the programming process, beginning with a PIC32 fresh from the factory. We will do that on this page. We will begin by discussing the virtual memory map of the PIC32. To discuss the virtual memory map, it is useful to know hexadecimal (hex, or base 16) notation, where each digit of a hex number takes one of 16 values, 0...9, A...F. Since 16 = 2^4, a single hex digit represents four digits of a number written in binary (base 2). The table below gives examples.

Hex	Binary	Base 10
7	0111	7
D	1101	13
B5	1011 0101	181

To distinguish hex and binary numbers from base 10 numbers, we begin the numbers with 0x and 0b, respectively. For example, 0xA9 = 10*16^1 + 9*16^0 = 0b10101001 = 1*2^7 + 0*2^6 + 1*2^5 + 0*2^4 + 1*2^3 + 0*2^2 + 0*2^1 + 1*2^0 = 160 = 1*10^2 + 6*10^1 + 0*10^0. The 0x and 0b conventions are also used in the C language.

The PIC32 Memory Map

The PIC32 has a virtual memory layout consisting of 4 GB (four gigabytes, or 2^32 bytes, where each byte equals 8 bits) of addressable memory. All memory regions reside in this virtual memory space at their unique respective addresses. This includes (flash) program memory, data memory (RAM), peripheral special function registers (SFRs), and configuration registers (e.g., bits that control the the system clock period and other functions). For example, the peripheral SFRs begin at virtual memory location 0xBF800000, where each "hexadecimal" number (0...9, A ... F) represents four bits (e.g., B = 1011 in binary).

can execute from data memory

FMT to physical memory. as programmer, only need to know virtual.