Summary

If youve gotten this far, many of the riskiest, most tedious steps are behind you. A few blinking LEDs and ASCII characters on a terminal might not impress your great aunt, but rest assured, they represent significant progress.

Youve verified basic access to the essential devices (memory and serial port) and youve created a function in C. The next step is to build a simple putchar () and getchar () in C, based on what youve already done in assembly language. This allows you to throw printf on top. In short, you have a working computer!

Finally, Ive said this before, but it continues to be very important. Take very small steps throughout this early boot stage. Do nothing fancy. Make sure cache is turned off and do not optimize any of the C functions. Slow and steady progress is good progress here.