2.4 Memory

The SRAM memories are accessed at their address in a memory space for both reads and writes at any granularity (byte, half word, or word). No special controller is needed to access the SRAM memory.

Flash memories are accessed for read at their address in memory space. Read granularity is byte, half word, or word. FC erases and writes the Flash memories. The following table lists the Flash memory access of different devices.

Table 2-2. Flash Memory Access
DevicePage
Read Word (Bytes)Write Word (Bytes)Size (Bytes)Rows per Page
PIC32CX-BZ3 16410244
PIC32CX-BZ632810244
Note: The information on the PIC32CX-BZ3 is provided for comparison and reference purposes.

The FC supports erase for the entire Program Flash Memory (PFM), or page erase for the unprotected pages. The following table lists the programming of different devices.

Table 2-3. Program Flash Memory Programming
DevicesSingle ProgramQuad ProgramRow Program with Built-in DMA for Reading Data from SRAM
PIC32CX-BZ3 word (4 bytes)8 words (32 bytes)4 / 8 word buffer
PIC32CX-BZ62 words (8 bytes)16 words (64 bytes)4 / 8 word buffer
Note: The information on the PIC32CX-BZ3 is provided for comparison and reference purposes.
Additionally, there are NVR pages (Boot Flash Memory (BFM)) separate from the Program Flash Memory (PFM) partition, where:
  • One page is allocated to Factory Test Memory
  • One page is allocated to Cal Space (called OTP page)
  • One page is allocated to Boot/Device Configuration (BCFG)

The following table lists the NVR pages of different devices.

Table 2-4. NVR Pages Information
DevicesNVR Total SizeNVR Total Pages NVR Pages for User Boot Code
PIC32CX-BZ3 32 KB85
PIC32CX-BZ676 KB1916
Note: The information on the PIC32CX-BZ3 is provided for comparison and reference purposes.

Each NVR page has write-protect capability. Factory Test Memory is not programmable by the user.

Partial writes are supported, but on partial write only bits that are ‘1’ can be set to ‘0’. The user can erase the entire Flash memory except the OTP and Factory test memory pages using a dedicated FC command.

Refer to the device data sheet for Flash and SRAM memory size and the memory map of a specific device variant.