Altair kit up and running.
 

I put the finishing touches on my kit this morning, powered it up and ... WooHoo!! It worked like a champ :D

I couldn't believe it. I figured I must have made a mistake somewhere, but apparently not. It's been running a memory test for the last couple of hours with no problems at all.

Praise should go to Grant's beautifully crafted kit along with his detailed assembly instructions. They made it a breeze to put the kit together.

Yipee. Good for you! I'm a few weeks behind you. I'm about ready to start the LED installation on the last board. Any tips you'd like to share in that area?

I hope I have the same success as you!

Paul

Installing LEDs
 

That went smoothly. As Grant suggested, I inserted all the LEDs, attached the panels, then pushed the LEDs out as far as they could go and soldered them. I found it helped to slightly bend the LED leads to stop them sliding out while I was fiddling with attaching the panels. Don't bend them much, though, because you want the leads to be straight when you've finished soldering. Also, solder one lead on each LED then recheck their position before soldering the other lead; a couple of mine had slipped down slightly and it was a lot easier to reposition them with only one lead attached.

Good luck. Keep us posted on your progress.

I forgot to say... forget the memory test. : )

Visit the link below and run this code with an AM radio on top of the Altair (case off).

Experiment with placement of the radio and frequency setting. I've found that a cheap clock radio will pick up the sounds much better than a digital tuner...

http://www.digibarn.com/collections/...ein/index.html

Look for:

Try this with AM Radio:
000:003 Inx BX
001:170 Mov A,B
002:241 And C
003:075 Dec A
004:302 Jnz 000:003
005:003
006:000
007:303 Jmp 000:000
010:000
011:000

If you want you can also enter in the historic "fool on the hill" listing, but it takes a lot longer. :)

Here are some pictures of his kit:

http://media.diywelder.com/images5/070307-IMG_0759.jpg

http://media.diywelder.com/images5/070307-IMG_0768.jpg


http://media.diywelder.com/images5/070307-IMG_0809.jpg

http://media.diywelder.com/images5/070307-IMG_0807.jpg

http://media.diywelder.com/images5/070307-IMG_0810.jpg

http://media.diywelder.com/images5/070307-IMG_0806.jpg

An update from Geoff... I sold him an extra 4 slot motherboard along with his kit and he wanted to test it out! :)

You have done a GREAT job! :)

http://www.altairkit.com/images/cust...p-IMG_0825.jpg


http://www.altairkit.com/images/cust...p-IMG_0827.jpg


http://www.altairkit.com/images/cust...p-IMG_0828.jpg



You have done a GREAT job! :)

Progress
 

I'm working on getting the machine to boot from an Altair 8" floppy drive. It's not there yet, but I do have it booting from a paper tape image of 8k basic.

Baby steps.

http://www.solivant.com/misc_images/altair_8kbas.jpg

I hate to admit this, but I have not had the time to make MY Altair replica do this! :) Of course with a real Altair...

Keep the pictures and updates coming! :)

A little more progress
 

I still don't have it booting into Altair DOS yet, but I did get Disk Extended Basic 5.0 running and accessing the disk, so I know my controller cards and drives are working. That's further than I got when I was trying to get my 8800b working.

http://www.solivant.com/misc_images/...diskbas_50.jpg

Got it booting into DOS
 

Finally, it boots into Altair DOS using a bootloader in PROM. Set a few switches, hit RUN, wait a few seconds and bam! there's DOS. Almost like a modern computer.

Next up: getting CP/M running. That will take me a while, though, unless I can find someone who already has CP/M on Altair floppys.

http://www.solivant.com/misc_images/altair_dos.jpg

Just for fun, put the AM radio near the Altair and tune it to an unused frequency. Reading a disk and running a program can make some really neat robot sounds! :)

Did you see the thread about the 3.5" disk drive, CP/M, and tarbell controller? Wouldn't be compatible with MITS software...

The Altair32 emulator comes with a CP/M image. I wrote a basic program to transfer a disk RAW from the Altair to my Windows machine. I never got around to Windows -> Altair...

So have you gotten bored of watching the lights flicker when using the disk drive and running programs? :)

Why should getting DOS to run be harder than Basic? Why can't you get this far with the 8800B?

Yes, and that would be interesting. I'm not concerned about maintaining MITS compatibility; in fact, I'd probably move the 8" drives back to the 8800b and keep that one as an all original machine.
I'll look into that. I'm not sure yet how I'll transfer the image to the Altair floppys, I'll have to figure that out.
Not yet, in fact I quickly got to the stage where I could tell quite accurately whether a disk access was going to fail long before the machine printed an error message.
The biggest problem with the 8800b was just that I didn't invest enough time. I tried to get it to boot from three of the floppys that I had and had no luck and I didn't want to keep trying in case I was trashing the disks. I intended to get back to it but never found the time.

This time around, I wrote a perl script to generate altair paper tape images of any binary so that I could load things easily via the serial port and then worked my way up from simple, small programs until I established that the disk hardware was healthy. In the end, the original problem with booting turned out to be that only a few of my floppys are readable. The ones I was trying to boot from before were simply bad. I'll have to write something to try to read raw sectors from them and see if there's anything I can salvage before they turn to dust.

I did the same thing, kind of... I wrote a 10-15 byte program that loads a predetermined amount of bytes from the serial port and then does a jmp 0000. I had the 2SIO jumpered for 19200 and could boot basic 5.0 in about 3 seconds. :) The program was small enough that I could use a terminal program with no delay between bytes. It was really screaming! The boot loader had to be modified for the specific binary image you wanted to transfer to the Altair.

It was a good beginning project for 8080 assembly!

transfer of programs
 

I have a friend that wrote a program to transfer programs either direction from a windows based machine. We used it to transfer Paper Tapes from a High Speed Paper Tape Reader to a Nova 1200 and then to a window based machine. He didn't want the program to ADD or Subtract anything from the programs, such as Hyperterminal will do, control characters and such.
I am sure that it would be able to do the same for the Altair. I CANNOT put the code on the WEB, nor give permission to use it.
But you can contact Him yourself !! :D :D :D
He is -- Bruce Ray of WildHareComputers.com Anyway I think it is dot Com .... Could be dot org ....
Its been awhile since I looked up his WEB site.
If nothing else just look up Wild Hare Computers on Google or such.
Thanks Marty

Any chance you could make duplicate tapes for the members here or post an exact binary image of the 8K BASIC tape?

I don't have any way to read or punch physical tapes (someone outbid me recently on a nice ASR-33 that was for sale quite close to me :mad: ). You'll find a collection of basic tape images, including 8k basic, in Rich Cini's Altair emulator code (http://www.altair32.com/Altair32code.htm). Download the latest version of the emulator and look in the files subdir for *.tap. The bootloaders needed to load the tapes are in files/loaders/tape_lodr.

Geoff.

Oh oh! You don't live in southern Vermont, do you? :eek:

Heh. No, I'm in Minnesota. And I don't hold a grudge, anyway :D

Hey! I'm in Minnesota too and I just got an ASR-33 :)

but I don't think it was the same one you were bidding on. Mine came from an
estate. It had a few issues but I've mostly restored it. Tape reader and punch are
working OK, although I don't yet have it on 20mA loop. Building an RS232 converter
for that and then I'll be able to hook it to a number of systems here.

Amazing piece of machinery.

Chris

disk basic
 

Hi Geof;
Do You know where disk basic is started from -- is it from 00000 or 0100h like CPM or somewhere else, I don't have an Altair Disk Drive, But I have it on Paper Tape, and would like to try and see if I can get it to run from the tape. I made the Tapes with an (RS-232) serial Paper Tape Punch, but don't Know where to start it from. And if it is Loaded straight through like an image file or with a Special Loader like the other Basics or some other loader. I do have a Tarbell Disk Controller, but I am not sure if it works or not.
THANK YOU Marty

I have a tape image of ALTAIR BASIC 5.0 [14JUL78] [DISK EXTENDED VERSION], I don't remember where I got it from, and it starts at 0000h. It's not a straight binary image, it needs to be loaded with a standard Altair tape boot loader, either the MBL running from a PROM, or one toggled in on the front panel. If you don't have MBL, you have to be sure to use the correct first stage loader for your tape. In either case, you have to set the sense switches correctly to tell the loader and Basic which terminal device to use. Let me know if you don't have a copy of the first stage loader and the switch settings, I can probably dig them out of my manuals.

Geoff.

basic
 

Hi Geoff;
Thank You for your Prompt reply. I have the first stage loader, both of them , one for the 4K Basic and the other for 8K and 12K Basic and the correct settings for the Switches. What I Don't have is a listing for the MBL Eprom. Once I have a listing I can Put it into 25(27)08 or a 25(27)16 Eprom. and put it into my machine.. I have a (I Think) a SSM PB-1 Eprom Porgrammer for the 2708 or the 2716 Eproms and a prolog M-980 for the 2516 Eproms. Just don't have a listing, I also have a 1702 Eprom card, just for reading not writing on an S-100 Buss Card.
THANK YOU Marty

Grant posted a hex dump of MBL some time ago in the files section of the Yahoo altaircomputerclub. I recently disassembled that back to source and added some comments. Take a look at:

www.solivant.com/altair_bootloaders/misc/mbl.asm

I use the spasm assembler so you may have to make some minor syntax changes if you use another one. I used it recently to load tapes of different vintages and it works great. You do have to play some games with the sense switches if you're loading something older than Basic 4.0 (see the comments in the file), but it's still much better than toggling in a loader every time.

Geoff.

Basic
 

Hi Geoff;
THANK YOU !!!!!!!!! THANK YOU !!!!!!!!!!!! This is Just what I needed, it will be a little while before I have the time to put it into an Eprom, But, at least I have something to work with... THANKS AGAIN Marty

That is GREAT work Geoff! How long did it take you to do that one?

Mbl
 

Hi Geoff;
I have the program Hand Dissassembled.. And am wondering if I could get the link for the Hex or Octal listing , to compare it with. I am using my BugBook III, for 8080 op codes and Hex and Octal numbers. I also have the other Bug Books ( I thru VI, except IV which was never made) THANK YOU AGAIN Marty

Not too long, less than a day. It helped that I had previously done the same thing to the 2nd stage tape loader and about half of the MBL is taken directly from that.

Sorry, Marty, I haven't had my coffee yet and I don't quite follow that. If you need the original hex dump that I used that's in groups.yahoo.com/group/altaircomputerclub under Files->EPROMs. You may have to join the group to access the Files section if you're not already a member. It's worth joining anyway even if you don't want access to that file.

What are you disassembling? If you need me to assemble MBL for a particular address, I'll be glad to do that and send you the resulting binary.

Geoff.

Mbl
 

Hi Geoff;
I used the wrong word, that can happen late at night, when up and still half asleep, and trying to get back to sleep, by doing something for a short time. I assembled it by hand. I don't have an assembler for the 8080 except for listings for some of my machines. I have one which I like for my Digital Group machine, which I would like to put on my Altair, but I also would have to also transfer the whole operating system, which I want to do, (but would need to transfer the I/O from Digital Group to Altair I/O) but don't have enough experience to do so with 8080 op code , yet. The operating system is called ICOSE and was written for the Digital Group Machine, but not by them. I also have two assemblers for the 8080 by Scelbi. (I Think)
THANK YOU Marty

putting parts in
 

Hi to all;
When assembling the circuit boards, I would recemend going from short height to higher, in other words I would put in the jumpers, then caps , then the resistors, then the sockets and so forth. not as the manual shows the other way around. they are easier to put in and solder that way also....
good luck to all... Thanks Marty