[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Resources to learn C



On Sat, 2009-04-04 at 20:42 -0700, john wendel wrote:
> You had it easy with your punched cards. I once worked on a box that 
> required toggling in the boot loader code via switches on the front 
> panel. But at least I never had to program in raw binary, the box had
> an assembler.

At college, we were tasked with programming a washing machine sequence
on 8085 breadboard development kits.  You had to program in I/O
sequences for the solenoids, and timed fill cycles (like that's going to
work with different water pressures!), timed wash, rinse, and spin
cycles based on the CPU clock.  Oh, and you had to put together the
hardware.  The CPU was on board, but other hardware and devices weren't.

Those kits gave you a hex keypad to enter your memory addresses and
opcodes, and a 6 digit LED display to see what you're doing, plus a few
status LEDs.  You wrote a brief for your program on paper, worked out
what functions would do what you needed and wrote the appropriate
mnemonics on the next column in the paper, then you wrote in the opcodes
for them - human compiling.

The timing washing cycles were all over the place because the developer
kits didn't specify their clock speed (which was different on each kit,
anyway).

We had another project, I can't remember what for, that did include
putting DIP switches in to toggle code into RAM that we'd added, too.
Those tiny things have to be amongst the worst way to hand enter binary.

-- 
[tim localhost ~]$ uname -r
2.6.27.21-78.2.41.fc9.i686

Don't send private replies to my address, the mailbox is ignored.  I
read messages from the public lists.




[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]