OT: Pigeons better at multitasking than humans

They're superior at search & rescue too:

An 8051 is a lot better at some types of multitasking than either. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net

I once wrote a pre-emptive RTOS for the MC6800 (the 8-bit two-phase-clocked NMOS one, not the 68K. I did the 68K later). [1]

I wrote it in pen, in Juneau Alaska, and mailed a few sheets per day back to the company in New Orleans; they typed it and assembled it. It had one bug.

It worked pretty well.

[1] horrible instruction set. There was no opcode to push the index register onto the stack.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

They fixed that and more in the 6809.

Fun. I wrote a predictor-corrector differential equation solver on an HP41C. (Still have it somewhere here, I expect.)

In my day we used to defrag disks by editing the inodes by hand, with magnets. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net

I'd rather go with the RCA 1802. My first computer. Easy to program. Still available today. Good for space hardening.

I never worked with the 6809. The 6803 was an upgraded 6800, "D" pseudo register, and it would push X onto the stack.

The 68K is a beautiful machine. Too bad IBM went with X86, which is a real dog.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

I simulated a steamship on an HP9100 desktop calculator. Cool machine.

Paper tape was much more touchy-feely.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

Especially 5 channel paper tape, edited at 5 cps.

You can still see an Elliott 803 running machine at The National Museum of Computing, and the museum staff will whip out the circuit diagrams and discuss them with you - my kind of museum.

The world's oldest operating computer is in the next room.

We totally agree on the 68k. IBM had a big stake in Intel so that is the way it went.

You should take a gander at the 6809 manual just to see how much better than the 6800 it was. I wrote a lot of assembly for the 09.

IBM actually went in several different directions, almost simultaneously. The System 9000 (1982) was IBM's 68000 based Xenix box, but the lowest price option was that PC thingie.

I recall interfacing a (Wico?) trackball to a 9000; it was someone else's machine, though, so never really used it.

I have a 9000/200 that has the 68020 processor. I use it to service the HP70000 test equipment.

Cart -> Horse

You are right. Just old memory working here.

But IBM did have agreements with Intel from other products using Intel devices.

The reason they used Intel, rather than Moto, was because in a pinch they could buy them if they went South. They did, and they did (to the tune of 25%, IIRC). Moto was too big to leverage. But all that came after the PC took off.

I used paper tape on the original Data General Nova. We had one in the UBC undergraduate physics lab, and used it for solving a 2-D partial differential equation (Laplace) as part of the course. It had a super-modern *8-bit* paper punch rather than 5-bit Baudot.

When I was an undergrad, I had this research assistantship doing simulations of interstellar giant molecular clouds, for Prof. Bill Shuter (a great guy) who had a millimeter-wave telescope at UBC. The original version of the source code came as a hard-copy report from a guy at a Danish observatory. I couldn't type back then, so I had the keypunch folks type it into a card deck and then check it on the card verifier. I used to carry round card boxes, mostly for the lulz (bit of an anachronism there). ;)

A year later, all that stuff was gone.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net

performed

) t

I used a (remote) PDP-8 with an ASR-33 teletype as my local interface to co llect the data (via the A/D converter on the remote PDP-8) for my Ph.D., wo rk - it followed the courses of some 60-odd chemical reactions (all NOBr to NO + Br2) and recorded at least a few hundred - sometimes more - data poin ts for each reaction.

Every last data point got punched out (as six digits - two for amplitude in crement and four for time increment) onto eight-channel tape on the ASR-33 and the tap pushed through a tape-to-card converter for processing on an IB M 7044 (which I got to run, on my own, from 2:00am to 6:00am on the days wh en I could book it). Kept me busy in 1968 and 1969 - getting together the g ear that could feed the PDP-8 kept me busy in 1996 and 1967.

--
Bill Sloman, Sydney

ormed

Thanks for the chuckle.

Actually, there were multiple codes used in the computers in the 1960's. The Elliott computers used their own character codes for 5-track and

8-track paper tapes, and they were even not related to each other. The 5-bit code did not match the code used in Telex traffic.

It seems to me that there were codes for each manufacturer and all mutually incompatible. It was a huge relief when the ASCII (ISO-646) came along, but for me it was a good source of income gone bust.

--

-TV