The BV513_V2 is a small form factor PCB with a PIC32MX340H512 processor, Micro SD Card holder and a USB serial interface that provides power and main communications. When used with ByPic the SD Card system will read and and write FAT16/32 formatted files.

The layout makes the board ideal for data logging and many other applications. All of the ports are brought out to pads on the PCB. The PCB can be used stand alone, to carry other boards or it can be used with pins to plug into a larger motherboard.

Comparison with Arduino

Resource Links

  • Processor: PIC32MC3340H512
  • Flash: 512k
  • Ram: 32K
  • Speed: 80 MHz
  • ADC: 16 Channels, 10 bit
  • Comparators: 2
  • PWM: 5
  • Input Capture: 2
  • UARTS: 2 (UART 2 connected to FTDI chip)


This is the pin layout shown not to scale as the centre pin-outs round the CPU are in a square. All microcontrollers have alternate pin functions and this diagram shows the port names ate the top and some popular alternate functions at the bottom. Some pins have several functions, not all are shown.

The BV513_V2 has an on board 5V and 3.3V regulator.

PCB Layout

** There is also a copy of this in the data sheet (link at head of this text)


The processor is clocked from its own internal oscillator without the need for an external crystal. The crystal that is provided is for the slow oscillator (32KHz). This can be used for slow timing operations and it can also maintain some functions when used in low power mode.

Example code to flash the on board LED ten times

function flash10()
dim j
  for j = 1 to 10


The BV513 was first sold in July 2009, during 2010 it became clear that manufacturers of Micro SD card were reducing support for the SD interface that the BV513 used and so no more BV513's were manufactured until a replacement was found.

It turns out though that trying to improve the original design was very difficult and so the BV532_V2 is almost the same as the BV513 - sorry it took so long to get here.