1. A contest...with a prize!
With all the talk about the merits of various languages,
assemblers, disassemblers, etc., I thought this might be
of interest: my first ever computer program.
It was used on a daily basis by several people for over
a year at my place of employment.
The first person who can tell me what it does will receive
a luxurious, all expense p...hmmm. make that:
Lovely Gift Certificate for some burger place;
I'm on a limited budget.
Bonus & Hint: If you accurately describe the platform it runs on,
I will supersize that meal.
-- BEGIN CODE (46h bytes)
3A3AF806F551F801F55164213A2A7A82513006
-- CODE ENDS
BTW & FYI: this IS the language in which it was written!
Rules: you are allowed to disassemble this code if you:
1.Have a disassembler for the [deleted] computer, and
2.send me a copy (pleeeze!)
Irv
PS: sorry about the lack of comments :P
2. Re: A contest...with a prize!
At 14:26 01-06-98 -0400, you wrote:
>With all the talk about the merits of various languages,
>assemblers, disassemblers, etc., I thought this might be
>of interest: my first ever computer program.
>It was used on a daily basis by several people for over
>a year at my place of employment.
>
>The first person who can tell me what it does will receive
>a luxurious, all expense p...hmmm. make that:
>Lovely Gift Certificate for some burger place;
>I'm on a limited budget.
>
>Bonus & Hint: If you accurately describe the platform it runs on,
>I will supersize that meal.
>
>-- BEGIN CODE (46h bytes)
>3A3AF806F551F801F55164213A2A7A82513006
>-- CODE ENDS
>
>BTW & FYI: this IS the language in which it was written!
>Rules: you are allowed to disassemble this code if you:
>1.Have a disassembler for the [deleted] computer, and
>2.send me a copy (pleeeze!)
>
>Irv
>
>PS: sorry about the lack of comments :P
>
Well Irv beleive it or not I recognised those HEX bytes at first glance. I spent
so many hours in 1978 programming a CDP1802 machine on a Hexadecimal keypad and
only
LED for display (not even and hex display just binary code)
00 38 SKP ; skip next byte
01 00 ; data byte
02 F8 01 LDI 01 ; load immediate register D with 01
04 A1 PLO R1 ; put register D in low byte of R1
05 E1 SEX 1 ; set register X with 1
06 64 OUT4 ; out to device 4 M(R(X)) -> BUS
07 21 DEC R1 ; decrement R1
08 F0 LDX ; load register D via register X
09 A2 PLO R2 ; put register D in low byte of register 2
0A 6C INP4 ; input from device 4 (data send to D and M(R(X))
0B FA 0F ANI 0F ; AND immediate D with 0F
0D FB 0F XRI 0F ; XOR immediate D with 0F
0F C6 LSNZ ; long skip (skip 2 bytes) if D not 0
10 7B SEQ ; set Q output line. (this is a single bit output on CDP1802)
11 38 NBR ; skip next byte
12 7A REQ ; reset Q line
13 F0 LDX ; load register D via register X
14 FA 0F ANI 0F ; AND immediate D with 0F
16 FD 09 SDI 09 ; substract D immediate i.e D-09
18 3B 23 BNF 23 ; short branch to 23 if DF = 0
1A F0 LDX ; load register D via register X
1B FA F0 ANI F0 ; AND immediate D with F0
1D FD 90 SDI 90 ; substract D immediate i.e. D-90
1F 3B 23 BNF 23 ; short branch to 23 if DF = 0
21 30 27 BR 27 ; short branch to 27
23 82 GLO R2 ; get low byte of register 2 in D
24 51 STR R1 ; store D in memory via register 1
25 64 OUT4 ; output M(R(X)) to device 4
26 21 DEC R1 ; decrement R1
27 3F 06 BN4 ; short branch to 06 if EF4 = 0 (EF4 is an input line of
CDP1802)
29 7B SETQ ; set Q line
2A F8 90 LDI 90 ; load D immmediate with 90
2C B3 PHI R3 ; put D in hi byte of register 3
2D 23 DEC R3 ; decrement register 3
2E 93 GHI R3 ; get hi byte of R3 in D
2F 3A 2D BNZ ; short branch to 2D if D not 0
31 F0 LDX ; load D with containt of memory pointed by X i.e. D = (R(X))
32 FA 0F ANI 0F ; AND immediate D with 0F
34 3A 3A BNZ 3A ; short branch to 3A if D not 0
36 F8 06 LDI 06 ; load D with 06
38 F5 SD ; subtract D from memory i.e. M(R(X)) - D -> D, DF
39 51 STR R1 ; store D in memory via register 1 D->M(R(N))
3A F8 01 LDI 01 ; load D with 01
3C F5 SD ; M(R(X)) - D -> D, DF
3D 51 STR R1 ; D -> M(R(N))
3E 64 OUT4 ; output to device 4 via R(X) i.e. M(R(X) -> BUS
3F 21 DEC R1 ; decrement register 1
40 3A 2A BNZ 2A ; branch to 2A if D not 0
42 7A REQ ; reset line Q
43 82 GLO R2 ; low byte of R2 in D i.e. R2.0 -> D
44 51 STR R1 ; D -> M(R(1))
45 30 06 BR 06 ; branch to 06
(code deassembled by hand)
This is code for RCA CDP1802 microprocessor. The computer was probably a COSMAC
ELF
Popularized by "Popular electronics" in 1977 (or 1978).
I don't understand yet what is does. (what device was connected to output 4,
line Q
and input line EF4 ? )
On my machine there was a LED on the Q line so codes 7B and 7A was flashing de
LED.
I connected a speaker on that line too and produce sound effects with it.
I even code a program to play tunes.
Regards,
Jacques Deschenes
Baie-Comeau, Quebec
Canada
desja at globetrotter.qc.ca
3. Re: A contest...with a prize!
At 12:04 AM 6/3/98 -0400, Jacques Deschenes wrote:
>This is code for RCA CDP1802 microprocessor. The computer was probably a
COSMAC ELF
>Popularized by "Popular electronics" in 1977 (or 1978).
>I don't understand yet what is does. (what device was connected to output
4, line Q
>and input line EF4 ? )
>On my machine there was a LED on the Q line so codes 7B and 7A was flashing
de LED.
>I connected a speaker on that line too and produce sound effects with it.
>I even code a program to play tunes.
>---
Hoo! I didn't expect a reply so quickly.
You are correct (enough to win the prize - where shall I send
the coupons?)
I wondered if there was a "signature" in the machine code
that would be recognizable, and sure enough, there was -
strange how some things stick in your memory, even for 20
years.
This ran on an ELFII, which had a 2 hex displays connected
to output port 4 (64), a hex keypad, and an Input key
connected to input 4.
There was also a relay driven off the Q line, which supplied
110v ac to a device.
If you're interested in a perfect, working 1802 computer in
hirez graphics: Quote: "Compatible with Windows 3.1, 95, and NT,
as well as WABI (Sun), WINE (X-windows), SoftWindows (Mac),
and other Windows emulators. (And if you don't think it's
ironic to run a simulation of a 14-year-old microprocessor under an emulator
of an 8 year old operating system running on an expensive new personal
computer, then your sense of irony is obviously in
need of a checkup! 
"
>---
>---
Regards,
Irv
4. Re: A contest...with a prize!
Irv:
Could you please check the U.R.L?.
I cannot reach it...
Thanks.
Jesus.
>>---
>>---
5. Re: A contest...with a prize!
Jacques Deschenes wrote:
>Well Irv beleive it or not I recognised those HEX bytes at first glance.
>I spent so many hours in 1978 programming a CDP1802 machine on
>a Hexadecimal keypad and only LED for display (not even and hex
>display just binary code)
There's a "Real Programmers" joke in here somewhere...
I'm impressed, and a bit frightened.
-- David Cuny
6. Re: A contest...with a prize!
I, too, had one of those 'euphoric' experiences when I read your response!
It was a bright, yet dull sensation that started in the palm of my hand and
proceeded down through..... No, wait, that was when I was healed with my
hand touching a television screen,
Anyway. I have never experienced that environment, but I feel a sort-of
kinship. Although I did not touch my first computer until 1982. IBM Series I.
As long as I am waxing philosophical, this is a great chance for all of the
younger programmers to acknowledge the wealth of experience they have
available to them on this list. As a beginner, I would have relished the
chance to read some of these discussions on logic, design, etc. I think
that is why many of you are so patient and level headed with your responses
to the 'simple' or 'intro' questions.
Let's NOT separate the lists.......
<******** ORIGINAL MESSAGE FOLLOWS *********>
Well Irv beleive it or not I recognised those HEX bytes at first glance. I
spent so many hours in 1978 programming a CDP1802 machine on a Hexadecimal
keypad and only
LED for display (not even and hex display just binary code)
00 38 SKP ; skip next byte
01 00 ; data byte
02 F8 01 LDI 01 ; load immediate register D with 01
04 A1 PLO R1 ; put register D in low byte of R1
05 E1 SEX 1 ; set register X with 1
06 64 OUT4 ; out to device 4 M(R(X)) -> BUS
07 21 DEC R1 ; decrement R1
08 F0 LDX ; load register D via register X
09 A2 PLO R2 ; put register D in low byte of register 2
0A 6C INP4 ; input from device 4 (data send to D and M(R(X))
0B FA 0F ANI 0F ; AND immediate D with 0F
0D FB 0F XRI 0F ; XOR immediate D with 0F
0F C6 LSNZ ; long skip (skip 2 bytes) if D not 0
10 7B SEQ ; set Q output line. (this is a single bit output on
CDP1802)
11 38 NBR ; skip next byte
12 7A REQ ; reset Q line
13 F0 LDX ; load register D via register X
14 FA 0F ANI 0F ; AND immediate D with 0F
16 FD 09 SDI 09 ; substract D immediate i.e D-09
18 3B 23 BNF 23 ; short branch to 23 if DF = 0
1A F0 LDX ; load register D via register X
1B FA F0 ANI F0 ; AND immediate D with F0
1D FD 90 SDI 90 ; substract D immediate i.e. D-90
1F 3B 23 BNF 23 ; short branch to 23 if DF = 0
21 30 27 BR 27 ; short branch to 27
23 82 GLO R2 ; get low byte of register 2 in D
24 51 STR R1 ; store D in memory via register 1
25 64 OUT4 ; output M(R(X)) to device 4
26 21 DEC R1 ; decrement R1
27 3F 06 BN4 ; short branch to 06 if EF4 = 0 (EF4 is an input line of
CDP1802)
29 7B SETQ ; set Q line
2A F8 90 LDI 90 ; load D immmediate with 90
2C B3 PHI R3 ; put D in hi byte of register 3
2D 23 DEC R3 ; decrement register 3
2E 93 GHI R3 ; get hi byte of R3 in D
2F 3A 2D BNZ ; short branch to 2D if D not 0
31 F0 LDX ; load D with containt of memory pointed by X i.e. D =
(R(X))
32 FA 0F ANI 0F ; AND immediate D with 0F
34 3A 3A BNZ 3A ; short branch to 3A if D not 0
36 F8 06 LDI 06 ; load D with 06
38 F5 SD ; subtract D from memory i.e. M(R(X)) - D -> D, DF
39 51 STR R1 ; store D in memory via register 1 D->M(R(N))
3A F8 01 LDI 01 ; load D with 01
3C F5 SD ; M(R(X)) - D -> D, DF
3D 51 STR R1 ; D -> M(R(N))
3E 64 OUT4 ; output to device 4 via R(X) i.e. M(R(X) -> BUS
3F 21 DEC R1 ; decrement register 1
40 3A 2A BNZ 2A ; branch to 2A if D not 0
42 7A REQ ; reset line Q
43 82 GLO R2 ; low byte of R2 in D i.e. R2.0 -> D
44 51 STR R1 ; D -> M(R(1))
45 30 06 BR 06 ; branch to 06
(code deassembled by hand)
This is code for RCA CDP1802 microprocessor. The computer was probably a
COSMAC ELF
Popularized by "Popular electronics" in 1977 (or 1978).
I don't understand yet what is does. (what device was connected to output
4, line Q
and input line EF4 ? )
On my machine there was a LED on the Q line so codes 7B and 7A was flashing
de LED.
I connected a speaker on that line too and produce sound effects with it.
I even code a program to play tunes.
Regards,
Jacques Deschenes
Baie-Comeau, Quebec
Canada
desja at globetrotter.qc.ca
<*************** END OF ORIGINAL MESSAGE ************>
Joe Phillips, Assistant Director
Information Technology Services
Texas Wesleyan University 817-531-4284
7. Re: A contest...with a prize!
> Anyway. I have never experienced that environment, but I feel a sort-of
> kinship. Although I did not touch my first computer until 1982. IBM Series I.
I inherited a Commodore KIM-1, a bit more advanced than the COSMAC. Fun
device -- people had even come up with a MicroChess for it, and various
little games. You could even hook it up to a TTY and talk to it with a
"regular" terminal.
Alas, the only assembly I know well is 6502 assembly. Those were the days.
--
Cameron Kaiser * spectre at sserv.com * http://www.sserv.com/
--
Visit the leading Internet starting point today!
http://www.sserv.com/
--
8. Re: A contest...with a prize!
At 02:06 PM 6/3/98 -0400, Cameron Kaiser wrote:
>I inherited a Commodore KIM-1, a bit more advanced than the COSMAC. Fun
>device -- people had even come up with a MicroChess for it, and various
>little games. You could even hook it up to a TTY and talk to it with a
>"regular" terminal.
>
>Alas, the only assembly I know well is 6502 assembly. Those were the days.
>
Hmm.. I finally had to toss the Teletype - it was taking up space
I needed for other things. Besides, every time it was turned on,
lights dimmed all over the neighborhood.
I still have a KIM-1, along with a pile of software.
Regards,
Irv
9. Re: A contest...with a prize!
At 10:00 AM 6/3/98 -0500, you wrote:
>I spent so many hours in 1978 programming a CDP1802
>machine on a Hexadecimal
>keypad and only LED for display (not even and hex display just >binary code)
>Jacques Deschenes
For those who don't know, the 1802 (RCA product) was a computer
you could build with a soldering iron, some wire, and about $25
On the other hand, it was one of the few modern computers that
you could easily out-compute with a pencil and paper...that was
also the way you assembled programs for the thing. You generally
had to make your program and data fit into 256 bytes.
People learned a lot about programming, working under those
constraints.
Regards,
Irv
10. Re: A contest...with a prize!
- Posted by Ralf Nieuwenhuijsen <nieuwen at XS4ALL.NL>
Jun 03, 1998
-
Last edited Jun 04, 1998
>On the other hand, it was one of the few modern computers that
>you could easily out-compute with a pencil and paper...that was
>also the way you assembled programs for the thing. You generally
>had to make your program and data fit into 256 bytes.
>People learned a lot about programming, working under those
>constraints.
Wow, where can you get those things?
At school we have these bords where you can plug an input, do some action
with it and then output something.
Like, your input is generated by a pulse generator, it goes from 1 Volt to 5
Volt, within some time you set it to. Then you plug that input in a 'NOT'
operator or an 'AND' operator and you can use LED's, A small beeper or a
relay to output the result. You can input any type of input actually, also
sensors. Pretty neat thing actually. We have to use it a lot.
I consider that to be the base of programming. You let it make a decision
based upon some input resulting in some output. The decision is split down
into very small decisions, which you use to explain the computer the more
complex decisions.
What does that RCA thing do ?
Ralf
11. Re: A contest...with a prize!
At 08:55 PM 6/3/98 +0200, you wrote:
>
>Wow, where can you get those things?
>What does that RCA thing do ?
>
>Ralf
>
The 1802/1805 chip is the heart of the Voyager, Viking and Galileo
spacecraft. Why? Because it's built with silicon on sapphire,
so it's fairly immune to radiation damage.
Harris Semiconductor makes it now (used to be RCA)
You don't have to buy the chip: here is a life-size *simulated*
computer, free of charge: (a beautiful job with graphics, too)
Regards,
Irv
12. Re: A contest...with a prize!
----------
> De: Irv <irv at ELLIJAY.COM>
> Fecha: miércoles 3 de junio de 1998 22:39
>
> The 1802/1805 chip is the heart of the Voyager, Viking and Galileo
> spacecraft. Why? Because it's built with silicon on sapphire,
> so it's fairly immune to radiation damage.
It was chosen also because the extremely low power draining. I was using
also one self-made ELF and I recall powering it from a dry battery for
days.
I moved after to the Motorola 6802, faster (but not better), and at that
time there were better cross assemblers for the minicomputers in vogue. I
keep my self made 6802 development system: 6 7-segment LEDs, one PIA, 1
2708 EPROM, 16 key keyboard, cassette loader... Was a luxury at that
time...
JesusC
13. Re: A contest...with a prize!
- Posted by Jacques Deschenes <desja at GLOBETROTTER.QC.CA>
Jun 03, 1998
-
Last edited Jun 04, 1998
At 01:05 03-06-98 -0700, you wrote:
>Jacques Deschenes wrote:
>
>>Well Irv beleive it or not I recognised those HEX bytes at first glance.
>>I spent so many hours in 1978 programming a CDP1802 machine on
>>a Hexadecimal keypad and only LED for display (not even and hex
>>display just binary code)
>
>There's a "Real Programmers" joke in here somewhere...
>
>I'm impressed, and a bit frightened.
>
>-- David Cuny
>
Don't worry David my words where a little exagerated. I first glance it was more
an intuition that a certitude. Then I took the CDP1802 programmer manual in my
book shelf an began to disasemble it. After a few bytes my intuition was
confirmed.
This computer was the first I bougth, I was young an very anthousiast. Like the
first love one never forget those things.
BTW Irv thanks for the offer but I not ungry for the moment.
Regards,
Jacques Deschenes
Baie-Comeau, Quebec
Canada
desja at globetrotter.qc.ca
14. Re: A contest...with a prize!
Joe Phillips wrote:
> I, too, had one of those 'euphoric' experiences when I read your response!
> It was a bright, yet dull sensation that started in the palm of my hand and
> proceeded down through..... No, wait, that was when I was healed with my
> hand touching a television screen,
>
> Anyway. I have never experienced that environment, but I feel a sort-of
> kinship. Although I did not touch my first computer until 1982. IBM Series I.
>
> As long as I am waxing philosophical, this is a great chance for all of the
> younger programmers to acknowledge the wealth of experience they have
> available to them on this list. As a beginner, I would have relished the
> chance to read some of these discussions on logic, design, etc. I think
> that is why many of you are so patient and level headed with your responses
> to the 'simple' or 'intro' questions.
>
> Let's NOT separate the lists.......
>
> <******** ORIGINAL MESSAGE FOLLOWS *********>
>
> Well Irv beleive it or not I recognised those HEX bytes at first glance. I
> spent so many hours in 1978 programming a CDP1802 machine on a Hexadecimal
> keypad and only
> LED for display (not even and hex display just binary code)
>
> 00 38 SKP ; skip next byte
> 01 00 ; data byte
> 02 F8 01 LDI 01 ; load immediate register D with 01
> 04 A1 PLO R1 ; put register D in low byte of R1
> 05 E1 SEX 1 ; set register X with 1
> 06 64 OUT4 ; out to device 4 M(R(X)) -> BUS
> 07 21 DEC R1 ; decrement R1
> 08 F0 LDX ; load register D via register X
> 09 A2 PLO R2 ; put register D in low byte of register 2
> 0A 6C INP4 ; input from device 4 (data send to D and M(R(X))
> 0B FA 0F ANI 0F ; AND immediate D with 0F
> 0D FB 0F XRI 0F ; XOR immediate D with 0F
> 0F C6 LSNZ ; long skip (skip 2 bytes) if D not 0
> 10 7B SEQ ; set Q output line. (this is a single bit output on
> CDP1802)
> 11 38 NBR ; skip next byte
> 12 7A REQ ; reset Q line
> 13 F0 LDX ; load register D via register X
> 14 FA 0F ANI 0F ; AND immediate D with 0F
> 16 FD 09 SDI 09 ; substract D immediate i.e D-09
> 18 3B 23 BNF 23 ; short branch to 23 if DF = 0
> 1A F0 LDX ; load register D via register X
> 1B FA F0 ANI F0 ; AND immediate D with F0
> 1D FD 90 SDI 90 ; substract D immediate i.e. D-90
> 1F 3B 23 BNF 23 ; short branch to 23 if DF = 0
> 21 30 27 BR 27 ; short branch to 27
> 23 82 GLO R2 ; get low byte of register 2 in D
> 24 51 STR R1 ; store D in memory via register 1
> 25 64 OUT4 ; output M(R(X)) to device 4
> 26 21 DEC R1 ; decrement R1
> 27 3F 06 BN4 ; short branch to 06 if EF4 = 0 (EF4 is an input line of
> CDP1802)
> 29 7B SETQ ; set Q line
> 2A F8 90 LDI 90 ; load D immmediate with 90
> 2C B3 PHI R3 ; put D in hi byte of register 3
> 2D 23 DEC R3 ; decrement register 3
> 2E 93 GHI R3 ; get hi byte of R3 in D
> 2F 3A 2D BNZ ; short branch to 2D if D not 0
> 31 F0 LDX ; load D with containt of memory pointed by X i.e. D =
> (R(X))
> 32 FA 0F ANI 0F ; AND immediate D with 0F
> 34 3A 3A BNZ 3A ; short branch to 3A if D not 0
> 36 F8 06 LDI 06 ; load D with 06
> 38 F5 SD ; subtract D from memory i.e. M(R(X)) - D -> D, DF
> 39 51 STR R1 ; store D in memory via register 1 D->M(R(N))
> 3A F8 01 LDI 01 ; load D with 01
> 3C F5 SD ; M(R(X)) - D -> D, DF
> 3D 51 STR R1 ; D -> M(R(N))
> 3E 64 OUT4 ; output to device 4 via R(X) i.e. M(R(X) -> BUS
> 3F 21 DEC R1 ; decrement register 1
> 40 3A 2A BNZ 2A ; branch to 2A if D not 0
> 42 7A REQ ; reset line Q
> 43 82 GLO R2 ; low byte of R2 in D i.e. R2.0 -> D
> 44 51 STR R1 ; D -> M(R(1))
> 45 30 06 BR 06 ; branch to 06
>
> (code deassembled by hand)
>
> This is code for RCA CDP1802 microprocessor. The computer was probably a
> COSMAC ELF
> Popularized by "Popular electronics" in 1977 (or 1978).
> I don't understand yet what is does. (what device was connected to output
> 4, line Q
> and input line EF4 ? )
> On my machine there was a LED on the Q line so codes 7B and 7A was flashing
> de LED.
> I connected a speaker on that line too and produce sound effects with it.
> I even code a program to play tunes.
>
> Regards,
>
> Jacques Deschenes
> Baie-Comeau, Quebec
> Canada
> desja at globetrotter.qc.ca
>
> <*************** END OF ORIGINAL MESSAGE ************>
>
> Joe Phillips, Assistant Director
> Information Technology Services
> Texas Wesleyan University 817-531-4284
Whoa!?! a cosmac ELF!?! jeez, I played with one when I was... five? (i'm 13
now, BTW...) blew out a diode checking for continuity... jeez, I never knew how
to program one... I typed in a number (8 digit, HEX) and pressed [enter?] and
nothing happend... I tried plugging it into the TV... WAH! never worked... BUT!
this isn't the first time I tried programming... started on Color Computer 3
disk
basic... taking programs out of Rainbow magazine, running it for errors, editing
the errors, and running it again. (3rd draft!) editing errors, running again.
and
then, it ran.... too bad I never remember it...
Oh boy, I'm turning out to be like my dad! :)
Thanx!
- "LEVIATHAN"
