Introduce yourself

[scotws]

Hello,

My name is Scot W. Stevenson, and I live in Germany, and just found this website. The last time I programmed a real, silicon 6502 was on the Vic-20 (that's VC-20 for Germans, because of some unfortunate phonetic effects), and my excuse at the time was that there wasn't really that much more you could do with it (I later upgraded to an Atari ST). For the last couple of days, I've been fooling around with the Symon simulator and Ophis, and am downright shocked at how much I still remember, and even more so that I forgot how much fun assembler is. It turns out I never threw out my copy of Leventhal either.

At the moment, I'm trying to figure out how doable a "real" SBC 65C02 would be. Garth Wilson's excellent primer (thanks for that) makes it seem possible, if not easy, but I pretty much lack the basic background knowledge of electronics. We'll see. At the moment, I'm having lots of fun with the simulators.

[BigDumbDinosaur]

scotws wrote:

Hello,

My name is Scot W. Stevenson, and I live in Germany...

Welcome to our 6502 world.

Quote:

At the moment, I'm trying to figure out how doable a "real" SBC 65C02 would be. Garth Wilson's excellent primer (thanks for that) makes it seem possible, if not easy, but I pretty much lack the basic background knowledge of electronics. We'll see. At the moment, I'm having lots of fun with the simulators.

A basic 65C02 SBC is not a difficult thing to design, as you may have gleaned from reading Garth's primers. For a lot of first-timers, the problems usually come in working out implementation details, such as I/O and methods of construction. Also, a first-timer often has a tendency to get too grandiose with their design, and ends up not completing the project due to excessive complexity. If you set realistic goals for a first design you will be okay.

In any case, don't be afraid to ask questions. We're never afraid to give answers and opinions.

[djmips]

scotws wrote:

Hello,
..am downright shocked at how much I still remember, and even more so that I forgot how much fun assembler is.

Hi! and welcome.

When I returned, for fun, to 6502 programming I was also shocked that the 6502 opcodes and programming had been burned to my 'ROM' apparently. I could still even remember the hardware addresses in the C64 without consulting a book. That's a lot better than some other things that I've learned!

- David

[scotws]

Thanks for the welcome, guys!

After reading up a bit more, I think the first big problem will be my almost complete lack of knowledge about basic practical electronics. (How basic, you ask? Well, the red wire is plus on a battery, right?) Interestingly enough, I had all the stuff like resistors, logic circuits, and Ohm's law in school, but it was completely theoretical. Which tells you a lot about the German education system, as good as it is.

So I've gone out and bought myself a little "Digitale Elektronik" experiment kit for 15 euros -- not much more than a 4 x NAND chip, a flipflop and a bunch of LEDs and resistors, but enough to get me stripping wires and plugging things into a breadboard (http://www.conrad.de/ce/de/product/1922 ... ik/0418047). The idea was also that if it turns out I hate this sort of stuff, I'd better find out before I invest in any serious equipment (turns out it's more fun than I thought, so no worries there). Building something with a pull down resistor, however small and silly, makes the concept much more real.

Speaking of equipment, that will be the next problem. I have a general multimeter, but I figure I'll need a serial-to-USB connector, an EPROM programmer, a power supply, stuff to wire-wrap, and an anti-static mat at some point -- anything else? None of it looks too expensive for the basic models, but I'll be spreading it out over time.

Lastly, thanks for the tip about starting small. I actually found myself thinking about grand stuff like a keyboard interface and some sort of display before I realized that the first step should be a 65c02, a chip for serial access over a terminal, some memory, and whatever glue chips. If that works, I can always build a second, more complex one.

For the next few weeks, I'll be sticking to putting the right resistor before the right LED and wiring flip-flops together while reading more and learning how to actually do stuff. Oh, and thanks again for the great info here!

[BigDumbDinosaur]

scotws wrote:

...So I've gone out and bought myself a little "Digitale Elektronik" experiment kit...(turns out it's more fun than I thought, so no worries there).

That's a good start. Once you understand the hardware basics it gets a lot easier.

Quote:

Speaking of equipment, that will be the next problem. I have a general multimeter, but I figure I'll need a serial-to-USB connector, an EPROM programmer, a power supply, stuff to wire-wrap, and an anti-static mat at some point -- anything else? None of it looks too expensive for the basic models, but I'll be spreading it out over time.

Purchasing a good logic probe wouldn't be a bad idea. I do the bulk of my digital troubleshooting with a probe and a DVM. I'm presuming your multimeter is a DVM and not an electromechanical unit like an old Simpson 260. If not, investing in an inexpensive one would be worthwhile.

Later on, once you really get into it, poking around on eBay might find you a good oscilloscope. As you ramp up clock speeds the 'scope can be a big help in figuring out why a circuit won't behave when it is run faster. A dual trace scope is even better.

Naturally, a reasonably good soldering station will be handy. Wirewrap will work out well at moderate clock speeds. Eventually if you stay with it, you'll want to make the switch to a printed circuit board, which means soldering small parts.

Quote:

Lastly, thanks for the tip about starting small. I actually found myself thinking about grand stuff like a keyboard interface and some sort of display before I realized that the first step should be a 65c02, a chip for serial access over a terminal, some memory, and whatever glue chips. If that works, I can always build a second, more complex one.

Good thinking. You'd be surprised with what you can do with a basic unit like what you are describing. It'll help you get more comfortable with the abstraction of logic design.

Quote:

For the next few weeks, I'll be sticking to putting the right resistor before the right LED and wiring flip-flops together while reading more and learning how to actually do stuff. Oh, and thanks again for the great info here!

Keep us posted on how things are going.

[mkarcz]

Quote:

Lastly, thanks for the tip about starting small. I actually found myself thinking about grand stuff like a keyboard interface and some sort of display before I realized that the first step should be a 65c02, a chip for serial access over a terminal, some memory, and whatever glue chips. If that works, I can always build a second, more complex one.

Good approach. Programming full keyboard requires surprisingly big amount of work:
http://6502cpu.blogspot.com/2012/12/i2c ... pdate.html

Keep it simple and build from the ground up.
"Complexity built from simplicity" - somebody once said. That is a good motto.

Welcome.

[LGB]

Hi All,

Since I've already sent some posts to the forum recently maybe it's a good idea to write here too.

I'm Gábor Lénárt from Hungary, speaking a hard language (Hungarian) while having hard time sometimes to try to express myself in English

I'm an "almost electrical enegineer" but I had some private problems in my life which rendered it impossible to finish my studies there. Since the years passed, lack of further studies in the topic & lack of experience over the lessons etc, many things just faded out (or even missed anyway). I built various circuits in my childhood (even my first radio when I was six), but not so much since my teenager period, and only "theoretical" things at the University then. Currently I'm working as "internet system engineer" at an Internet Service Provider.

Nowdays I've started more and more nostalgia about the good old times when I programmed my little sweet C64 and its CPU the 6510, which is basically a 6502 with some extra. So I decided to unite my two old hobbies and try to build "8 bit stuffs" then program them.

Why 65xx? Well, I often had the situation whishing "oh well, just one more register", or "how cool would it be to have a 32 bit 1Ghz 65xx-class CPU", etc, but still, that wouldn't be the same. 65xx family of CPUs has some "magic". For example it's simplier to deal with a Z80 in many aspects (from the view point of building an SBC too), but anyway, 65xx feels sweeter It's hard to explain, but maybe we don't need (and shouldn't) explain the meaning of "love"

[BigEd]

Exactly - it's love! Welcome!

[lak]

Hi,
I've visited this board many times and have just realized that I'm registered a year ago. I've enjoyed reading all messages, past and present, in the forums. I'm waiting to purchase a user-designed modern W65816 SBC preferably using W65xx peripherals, sd card with video graphics and decent amount of ram worthy of this processor (Real W65816+FPGA is ok too)
I'm from Singapore.

regards
lak

[whartung]

Welcome lak, I know some of the SBCs around are getting closer to that, but I don't think we have one quite all the way yet.

[kattbjorn]

Hello,

I'm 19 and i'm from Australia. I don't think i've had any experience with any 6502 computers. I got to use an old computer some time ago, all I knew how to do was load games off of tapes, pretty sure it had a Z80 anyway.

I don't know why I got interested in 6502 processors, pretty sure I was looking through Wikipedia and it came up. I read through all I could find, it all seemed so fascinating. It's all I seem to think about, on the train I think "I wonder if I could write this" or "I wonder if I could build that". I can't find anyone around me who wants to talk about it and I wanted to learn a lot more, so I figured joining this forum's a good enough idea.

I have built a project, it's The First Great 6502 Project from |Hackman's Realm. I only put it together a couple weeks ago. It didn't work at the time that I took the photo, I accidentally a few bytes out of the program, but the LEDs should be in an alternating pattern. I'm not sure what exactly to do with it next. I was thinking using it to convert ADB signal to PS/2, I have a few old Apple keyboards and since I found out they've got old-school ALPS switches in them I really want to be able to use it with my |PC. Optimally I want to get into robotics, but I know that's pretty far down the line.

I've been told it's a useless project, with Arduino controllers and Raspberry Pi units becoming more prevalent, but I guess I wanted to give myself a unique challenge. Either way, a skill surely can't be entirely useless.

If I left a pipe character somewhere please ignore it, my keyboard keeps producing them and i'm not sure why

[BigEd]

Welcome! You successfully built a computer on a breadboard: that's not useless! You must have got a grip on busses, control signals and address decoding. As to what to do next, whatever sparks your interest and takes you a step further.
Cheers
Ed

[BigDumbDinosaur]

kattbjorn wrote:

I'm 19 and i'm from Australia. I don't think i've had any experience with any 6502 computers. I got to use an old computer some time ago, all I knew how to do was load games off of tapes, pretty sure it had a Z80 anyway.

Welcome to our 6502 world.

Quote:

I don't know why I got interested in 6502 processors, pretty sure I was looking through Wikipedia and it came up. I read through all I could find, it all seemed so fascinating. It's all I seem to think about, on the train I think "I wonder if I could write this" or "I wonder if I could build that". I can't find anyone around me who wants to talk about it and I wanted to learn a lot more, so I figured joining this forum's a good enough idea.

A bloke by the name of Lance Lyon is down your way and runs a website devoted the Commodore 128, which as you know, had an 8502, basically a 6510 with higher clock rates available. His website is here.

Quote:

I've been told it's a useless project, with Arduino controllers and Raspberry Pi units becoming more prevalent, but I guess I wanted to give myself a unique challenge. Either way, a skill surely can't be entirely useless.

It's my opinion that those who devote their time to Arduinos and Pis aren't really learning anything about computer hardware. The Pi, in particular, is little more than a PC with a non-Intel architecture. Scratch-building an SBC (whether 6502 powered or not) is what really gives the insight into digital circuits. It also gives you a challenge when it doesn't work right.

BTW, you should focus on using the 65C02 or 65C816 instead of the NMOS 6502. The CMOS versions address the bugs and other assorted maladies in the NMOS part. The CMOS parts are also readily available through a number of electronics sources.

Quote:

If I left a pipe character somewhere please ignore it, my keyboard keeps producing them and i'm not sure why

I found that pipe and am now smoking it.

[Dajgoro]

kattbjorn wrote:

Hello,

I'm 19 and i'm from Australia. I don't think i've had any experience with any 6502 computers. I got to use an old computer some time ago, all I knew how to do was load games off of tapes, pretty sure it had a Z80 anyway.

I don't know why I got interested in 6502 processors, pretty sure I was looking through Wikipedia and it came up. I read through all I could find, it all seemed so fascinating. It's all I seem to think about, on the train I think "I wonder if I could write this" or "I wonder if I could build that". I can't find anyone around me who wants to talk about it and I wanted to learn a lot more, so I figured joining this forum's a good enough idea.

Welcome to the forum!

I started with the 6502 much like you, I think I was 19 as well at the time, now I am 21.
I build my own 6502 computer too, and over time I build an entire system around it.
Neither of my friends understand why I am building it, but I don't care about that, I just keep building it.

I hope you will have lots of fun with the 6502, and I guess you will learn lots of new stuff regrading electronics in general while building it!

[ElEctric_EyE]

kattbjorn wrote:

..."I wonder if I could write this" or "I wonder if I could build that"...I've been told it's a useless project...

This is awesome. Welcome... I had reignited my spark for the 6502 from remembering the old days of the C-64 and here you just had some innate desire to learn basic digital electronics, built around a CPU no less! If you can make your project work, it should give you great confidence.

Feel free to post your project here in the hardware thread. This forum is a great place to get some help and speed up the learning process.