The master controls each slave through a line called the slave select (SS), which it will drive low to indicate to a slave that it is required to receive or transmit. The master controls all interaction on the SPI bus, while the slaves only send or receive data when instructed to do so by the master. In addition, SPI requires one device to operate as a master, and other devices to act as slaves. This significantly simplifies the implementation at a hardware level, requiring little more than shift registers, and also means that the baud rate between devices does not have to be agreed on beforehand. SI-Prog is the programmer hardware interface for PonyProg. Unlike UART, SPI is synchronous, meaning data transfers are synchronized to a shared clock signal between the two communicating devices. At the moment it supports IC Bus, Microwire, SPI eeprom, the Atmel AVR and Microchip PIC micro. The ATATMEL-ICE-PCBA is a low cost version of powerful development tool for debugging and programming ARM Cortex-M based SAM and AVR microcontrollers with onchip debug capability without plastic encapsulation.

It is the method used by programming devices like the usbtiny to transfer programs to AVR microcontrollers and is a way to interface with SD cards, among other things. However before we can get a program loaded onto the chip, we need a good way to connect the SPI (. Serial Peripheral Interface (SPI) is a very useful data transfer protocol for microcontrollers. Now we will need to get more in-depth with the programming.

Atmel spi programmer