Many developers have had that “labor of love” project – the kind that keeps them up nights trying to get everything right, figuring out how to pass that one last hurdle. Woz was no different, and the recently open-sourced code – for non-commercial use, of course – brought back memories of the days he worked on it so long ago, finishing in Vegas no less.
Some of you know I used to work for Steve, so I reached out to him with a link to the his code…
Here’s his response:
On Nov 13, 2013, at 8:04 PM, ʞɐıuzoʍ ǝʌǝʇs wrote:
The MOST AMAZING code of my life…I could never do anything close to this much ‘out of any box’ stuff ever again…it was as amazing to come up with it as it seems to be reading my code. In some places I put numbers like (5) meaning that 5 cycles would be taken by that instruction – I had to count them all so the loops always sent a byte to the controller every 32 microseconds exactly. And there is no way to explain the 5-bit and 7-bit stuff but it extended the data from 13 sectors to 16 sectors. The 13-sector version was running in Las Vegas. The improvement to this 16-sector code is the part that I worked on every night for a month, nearly finishing each night around 2 AM (Denny’s milkshake) but repeating the whole process the next day because I had to keep getting the entire huge framework in my head each day. Finally I stayed one night until 6:30 AM and got it totally done. Jobs had been asking me every day when it would be done and that morning I told him that it was! This part of the low-level disk code was not Randy’s but I am so thankful for the parts he did so well too that made higher level sense out of this. I consider this code to be more like hardware than software.
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