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Steve Wozniak's floating point routines for the 6502

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Re: Steve Wozniak's floating point routines for the 6502

#61

Post by userbinator »

monocasa wrote: post #55
outworlder wrote: post #22

Earlier quoted context omitted.

> As a senior Java / CPP developer This makes me cringe. A "senior" engineer is defined by whatever role a company slots you in. This is compounded by adding programming languages to the mix. > I really wish I had done more embedded and assembly at school. I can't understand it or appreciate it. There is no hardware involved here, per-se. What is there is the 6502 instruction set, plus binary floating point calculati…

On Linux, a full asm program with syscalls isn't too bad. Here's one example: https://jameshfisher.com/2018/03/10/linux-assembly-hello-wor...

A 16-bit realmode DOS Hello World is also very simple, being less than 2 dozen bytes (8 bytes of actual machine instructions, and 15 bytes of message...) and something you can enter into DEBUG and run immediately if you have a 32-bit Windows system; on a 64-bit one, DOSBox or similar emulators will work well too:

    mov ah, 9
    mov dx, 108
    int 21
    ret
    db "Hello world!" 0D 0A "$"

Re: Steve Wozniak's floating point routines for the 6502

#62

Post by FpUser »

mothsonasloth wrote: post #12

As a senior Java / CPP developer, reading what Wozniak had written, it might have been some incantation in a forgotten language. I really wish I had done more embedded and assembly at school. I can't understand it or appreciate it. Maybe SW and HW shouldn't mix, bar a few visionaries who bridge both worlds?

Why should not they mix ? I now mostly work on high level code (C++, Python, Delphi/FreePascal/Javascript/etc ). But every once in a while fun project comes in. For example I had no problem creating 4 quadrant torque driven 3 phase AC motor controller using AT90USB1286 microcontroller from Atmel. Granted I did not use assembly for programming as plain C was good enough. Or police light flashing pattern controller on PIC32MX795. Fun fun fun ;)

Re: Steve Wozniak's floating point routines for the 6502

#63

Post by canada_dry »

justinjlynn wrote: post #45

Steve Wozniak is one of the few people of note in the tech industry who, the more I learn about them, seems more and more worthy of my respect. When I hear others speak of their sense of humour, how they stuck by their friends even when those friends clearly took advantage of them, the work and exemplary engineering skill they so clearly poured into their projects, their financial success and, then after having enjoy…

Maybe not in the same category (i.e. electronic design), but the other guy that I admire the hell outof is Adam Savage. The guy is just bloody brilliant at D-I-Y and, like Woz, a down-to-earth-nice-guy. I've had the great pleasure of meeting both men and they dispelled the myth about meeting your heroes.

Re: Steve Wozniak's floating point routines for the 6502

#64

Post by protomyth »

ananonymoususer wrote: post #58

The 8051 platform can present even more challenges for assembly language code developers than the 6502. It has been over 35 years since I wrote any 6502 code, and over 30 years since I wrote any 8051 code, but I remember the biggest issue on 8051 was the lack of RAM. You get a total of 384 bytes of RAM (256 bytes of normal RAM and 128 bytes of "zero page" RAM). When I needed to write floating point math functions for…

Yeah, Intel is an odd bunch. If I had to program an 8-bit machine again, I think the 6809 is still my favorite.

Re: Steve Wozniak's floating point routines for the 6502

#65

Post by spullara »

justinjlynn wrote: post #45

Steve Wozniak is one of the few people of note in the tech industry who, the more I learn about them, seems more and more worthy of my respect. When I hear others speak of their sense of humour, how they stuck by their friends even when those friends clearly took advantage of them, the work and exemplary engineering skill they so clearly poured into their projects, their financial success and, then after having enjoy…

My wife follows him on 4square, now Swarm. I wish he would eat at better restaurants so we might enjoy his company in the world longer.

Re: Steve Wozniak's floating point routines for the 6502

#66

Post by unoti »

empath75 wrote: post #17
mothsonasloth wrote: post #12

As a senior Java / CPP developer, reading what Wozniak had written, it might have been some incantation in a forgotten language. I really wish I had done more embedded and assembly at school. I can't understand it or appreciate it. Maybe SW and HW shouldn't mix, bar a few visionaries who bridge both worlds?

play the zachtronics games if you want a taste of it.

I did assembly on 6502, 6809 family, and 68000 for quite a few years. While I did enjoy Tis-100 and other zachtronics titles, those are actually quite a bit more challenging than real assembly programming. In real assembly you’re pretty much never limited to like 1 or 2 bytes of ram to work with. Zachtronics games are more like puzzle games than a real taste of assembly. For a real taste of assembly, write a little game in real assembly, or maybe calculate Fibonacci numbers in 6809 assembly, or maybe play with Chip-8.

Re: Steve Wozniak's floating point routines for the 6502

#67

Post by BurningFrog »

justinjlynn wrote: post #45

Steve Wozniak is one of the few people of note in the tech industry who, the more I learn about them, seems more and more worthy of my respect. When I hear others speak of their sense of humour, how they stuck by their friends even when those friends clearly took advantage of them, the work and exemplary engineering skill they so clearly poured into their projects, their financial success and, then after having enjoy…

Aside from being a saint, I think Woz singlehandedly jumpstarted the computer industry by 1-2 years with his genius early designs.

It would be 2017 now if it wasn't for him!

Re: Steve Wozniak's floating point routines for the 6502

#68

Post by BurningFrog »

bigred100 wrote: post #40
redis_mlc wrote: post #10

Woz was scary good at both hw and sw (author of Apple BASIC.) If you have time, go through his various Apple documents online. I believe he was never the same after his small plane crashed. (Back then, wealthy people used small planes like ATVs, and had about the same safety record.) I worked with another hw engineer of similar ability back in the 80s. Mind-blowing watching him just pick up a pen and draw out a compl…

I wonder why rich people have such a high urge to fly small airplanes. It seems to expose you to a lot of risk, which you could easily avoid (I’ve lived a considerable number of years without facing a single situation where I was likely to fly an airplane).

There is no other way to buy yourself past traffic.

Re: Steve Wozniak's floating point routines for the 6502

#69

Post by WalterBright »

paulsmith wrote: post #42
WalterBright wrote: post #13

Having written a lot of 8 bit assembler for the 6800 microprocessor for 2K eproms, I can attest it is a very different skill from writing modern software.

Would love to hear more about this - have you written on your experiences?

Just for fun, here's my IEEE 754 implementation of double precision floating point for the 8088:

https://github.com/DigitalMars/dmc/blob/master/src/CORE16/DO...

Re: Steve Wozniak's floating point routines for the 6502

#70

Post by nocman »

naikrovek wrote: post #50
redis_mlc wrote: post #10

Woz was scary good at both hw and sw (author of Apple BASIC.) If you have time, go through his various Apple documents online. I believe he was never the same after his small plane crashed. (Back then, wealthy people used small planes like ATVs, and had about the same safety record.) I worked with another hw engineer of similar ability back in the 80s. Mind-blowing watching him just pick up a pen and draw out a compl…

Lots of people were scary good at these things early on. Not everyone was as good as Woz, of course. When you can fit the entire architecture into your head, all the way down to the chips and board layout, you'll find that you're capable of quite a lot on that platform. A human with a skillet that has scaled up as much as computing hardware has scaled up is going to be virtually impossible to find, if not actually im…

"A human with a skillet" -- oh, I'm guessing skillset is what you meant to say.

I was feeling old and thinking I was ignorant of some new slang there for a few seconds.

:-D

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