[Kevin] attached a MicroSD breakout board to an Arduino-compatible clone. When the clone starts up, it searches the SD card for a file called ‘program.hex.’ ...

Meanwhile, the Arduino Mega is getting the same USB chip along with an ATMega2560 processor with twice the memory. Right now only 128K is available, but that's a software limitation and they're ...

SD cards can be accessed with two modes. The first is the SDIO mode, which is what cameras, laptops, and other card readers use. The second mode is SPI mode. SPI is slower, but much, much simpler.