Raspberry Pi Breadboard Madness

So I was working on my Raspberry Pi, getting SD cards and ethernet working over SPI so we can still use mass storage and networking while we rewrite the SD and USB drivers. I looked over at the side of my desk where all of this is on breadboard attached to my RPi and realised the insanity of it.

So let’s play spot the PCB:

• Raspberry Pi. This one’s easy!
• SparkFun FTDI Basic Breakout – 3.3V
• SparkFun Breakout Board for microSD Transflash
• SparkFun DeadOn RTC
• SparkFun Real Time Clock Module
• Olimex ENC28J60-H
• SparkFun PCA9306 Level Translator Breakout
• SparkFun Digital Temperature Sensor Breakout – TMP102
• SparkFun SOIC to DIP Adapter 20-Pin with 2x Atmel AT45DB161D
• Gadget Factory / Dangerous Prototypes Open Bench Logic Sniffer

Phew!

And yes, my Raspberry Pi has two SD cards and two ethernet controllers connected. The kernel and device tree blobs are loaded from the built-in SD and the root filesystem from the SPI SD card. The internet ethernet doesn’t work at the moment because we don’t have a USB driver in this kernel, so the SPI ethernet does the job for now!

A cross compiler is a compiler that runs on one platform/architecture but generates binaries for another platform/architecture. With devices like the Raspberry Pi, where you really don’t have much CPU or memory to work with, if you’re doing any heavy compiling (like when working on the kernel) a cross compiler is the only way to go. For example, I build all my Raspberry Pi kernels on my nice Sandy Bridge Xeon E3 home server where they compile in only a fraction of the time they would on the Pi.

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