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barythrin
July 21st, 2009, 12:20 PM
I'm not sure (not having a full understanding on the electronics behind such a system) whether or not this is a desirable project or experience but it sure is interesting. John Pultorak built a replica of this system and then documented the design to the level of potentially building your own. I'm a bit surprised at the high price but I suppose if he was tinkering around and using better parts that could happen.

http://echoesofapollo.com/resources/apollo-guidance-computer/

NeXT
July 21st, 2009, 08:10 PM
I remember hearing about this a year or so ago. I backed everything up regarding it including a pile of old documentation and burned all 300-some-odd megs of data onto a cd.
Me and a friend were planning to build a replica as well but we never got around to it before more pressing issues like employment came around.

channelmaniac
July 21st, 2009, 10:43 PM
Wow... I didn't realize they had 7400 logic that far back!

I thought they would've used ECL or RTL back then.

1964 for 5400 series with the wide temp range.

RJ

Dwight Elvey
July 22nd, 2009, 07:37 AM
Hi
I didn't see any thing about the original using TTL. It mentioned
using NOR logic. That would imply RTL or maybe DTL to me.
The only TTL that could have been used was a pile of 7438's and
these are NANDs. The fellow used TTL to replace not having any
of the original type of logic.
This might be a better project done in programmable logic.
There is a way to created the wired-and busses with tristate
devises. It does require that one use the chips with independent
control on each output.
Dwight

Chuck(G)
July 22nd, 2009, 05:47 PM
Yup RTL, probably 803/903-type, given the age. Compared to TTL, RTL is very simple--the 3-input NOR involves 3 transistors and 4 resistors. Operates at 3vdc.

If you wanted to be accurate without the original parts, you could probably make do with some transistor arrays and some external resistors.

The "core on a rope" thing would be harder to do, I think.

nige the hippy
July 23rd, 2009, 03:15 AM
That was a good read. Only now do I understand the significance of those "landing the LEM" games. I didn't realise that on the actual moon mission, Neil Armstrong had to fly the LEM in manually with dwindling fuel reserves. "Landing the LEM" was a simulation of a real life-or-death situation, with the question "could you do it?"
I think mr Pultorak's work is amazing. No he hasn't got an exact copy of the original, but what he has done is pulled together all the information, solved the undocumented problems, and done some real archeology. Hopefully some museum or other will get the resources together to build an even more accurate next iteration, while the chap's still fresh.

kiyotewolf
August 3rd, 2009, 04:39 PM
omg..

I've been wanting to find something like this for YEARS..

Oh wowowowowowowoowowowoweiiiiiiiiiiiiiiiiieee

O.O!!

* dies *



Yaaaaaaaaay



cool cool cool cool..






Lock de la Lion aka Kiyote Wolf

tezza
August 3rd, 2009, 06:00 PM
That was a good read. Only now do I understand the significance of those "landing the LEM" games. I didn't realise that on the actual moon mission, Neil Armstrong had to fly the LEM in manually with dwindling fuel reserves. "Landing the LEM" was a simulation of a real life-or-death situation, with the question "could you do it?"


Yea. I didn't understand the significance of the low fuel situation either until recently. Like you Nige, I now see the relevance of dwindling fuel in all those Lunar Lander games of the late seventies/early 80s..lol

In fact, I've been playing a few of them lately. Now that I've got most of my vintage hardware, I'm building up my software libraries. Almost all of my vintage machines seem to have a lunar lander-type game available for them somewhere. It just shows how popular it was.

Did David Ahl (BASIC Games) ever publish a text-only version of the game where you simply punch in numbers and you get numeric output based on the relevant equations (and an exclamation when you invariably crash of course)?. I have a vague memory that he did? If so, then I can say ALL of my machines could run a version of the game even my non-graphic CP/M ones :)

Tez

Marty
August 3rd, 2009, 06:45 PM
Hi;
The first versions in assembler were in text mode (non graphic), since that was all we had, :) I don't remember if it ever came out in Basic... I once had that book, but that was tooo long ago...
THANK YOU Marty

pavery
August 3rd, 2009, 10:11 PM
Did David Ahl (BASIC Games) ever publish a text-only version of the game where you simply punch in numbers and you get numeric output based on the relevant equations (and an exclamation when you invariably crash of course)?. I have a vague memory that he did? If so, then I can say ALL of my machines could run a version of the game even my non-graphic CP/M ones :)

Tez

He sure did, Tezza. In his Basic Computer Games (Microcomputer Edition) he includes 3 versions of Lunar LEM Rocket. All are text-based.

Also included is "Conversion to other Basics". He states what's involved in getting these programs to work on various classics, including Ohio Challenger, Imsai 8K Basic, PET Basic, Basic-E (CP/M).

I still have my original book. :D You'll have to borrow it!

Philip

tezza
August 4th, 2009, 03:42 AM
He sure did, Tezza. In his Basic Computer Games (Microcomputer Edition) he includes 3 versions of Lunar LEM Rocket. All are text-based.
........
I still have my original book. :D You'll have to borrow it!


Ah ha I thought so. Thanks for the offer Philip but I've actually got that book buried under piles of other stuff (books and manuals) in a box. I should fish it out for a bit of nostalgia.

I really enjoyed typing in and running those simple programs. Of course that was in the day when computers were magical toys and you were lucky to have one.

Tez