What kind of code is on 1980's, 1990's scope's/etc ? - Page 1
Forum section: electronics / testgear

author: MathWizard
author_rank: Super Contributor
timestamp: March 23, 2020, 06:06:16 pm
content: I know the names of a few modern computer prog. lang's, and would expect to see that type of code on new scope's/etc, from all companies, since everyone's on a modern computer writing the code these days.So what's it like for 80s/90s era tech ? Did most companies cook up there own code/lang, machine code/etc ? So you'd have to learn 10 books if you really wanted to dig into DSO's from 10 companies? Or maybe they are more similar, if there was less prog.lang./etc to choose from ?

author: rsjsouza
author_rank: Super Contributor
timestamp: March 23, 2020, 07:03:37 pm
content: Basically yes. Most equipment I see from this era uses custom code based in C or ASM.So yes, you used your elbow to brush bits on registers, after reading hundreds of pages of literature. Nice SDKs and libraries were scarce and cost money.

author: TK
author_rank: Super Contributor
timestamp: March 23, 2020, 07:06:30 pm
content: Most of HP test gear from the 80's use 68000 microprocessor with some sort of 80's RTOS

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2020, 07:12:36 pm
content: "1980's, 1990's" covers a lot of years but there wouldn't really be many CPUs to choose from.Most of them are probably either Z80 or 6800 (1980s) or 68000 (1990s).I doubt Intel would have been inside any of them, although there's bound to be somebody who knows different.

author: nctnico
author_rank: Super Contributor
timestamp: March 23, 2020, 07:18:18 pm
content: Quote from: Fungus on March 23, 2020, 07:12:36 pmNope. The Tektronix 2030 has an 8080 processor inside.Basically anything goes where it comes to programming languages. You can expect any kind of language. ASM, C, Ada, (compiled) basic and even Java (the later Tektronix TDS500/700 series hava a Java logo on their splash screen). The same goes for the OSses being used. You can find anything from bare metal, VxWorks, Unix-like OSses like Qnx, etc.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 07:25:23 pm
content: Interesting...I guess I'm basically clueless in this area, but I assumed that the hardware designers, especially back then, were focused on minimal hardware/ROM/etc. resources, and had to make their code as efficient and minimal and directed towards the specific manufacturers' A/D converters and other hardware they were using in the particular piece of equipment.Which implies to me that they would have some absolutely bare-bones and custom, vendor-specific assembly-type code, or at most maybe a tiny subset of a full-on language like a C interpreter or whatever.

author: nctnico
author_rank: Super Contributor
timestamp: March 23, 2020, 07:55:24 pm
content: Quote from: engrguy42 on March 23, 2020, 07:25:23 pmWhy would they do that? Test equipment never has been cost sensitive where it comes to the hardware. If you have a bunch $1000 ADC ASICs in an oscilloscope it isn't going to matter if you use a $5 or $50 processor in it. The cost of NRE is very high compared to sales volume; having to optimise software a lot is a road to going bankrupt. What you typically see is that the processing part is not really cut down for cost. Power consumption and size are much more important constraints.

author: edavid
author_rank: Super Contributor
timestamp: March 23, 2020, 07:59:49 pm
content: Quote from: nctnico on March 23, 2020, 07:18:18 pm2030? Were you thinking of a different model number?Anyway, the Tek 2246 series scopes use an 8088 CPU, which is why they have a snappier UI than the much more expensive 2465 series, which use a lowly 6800.The 7854 mainframe uses a TMS9900 CPU, oddly enough.QuoteTektronix even used Smalltalk - what a bad idea.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:02:36 pm
content: Quote from: nctnico on March 23, 2020, 07:55:24 pmThanks. I guess I was visualizing it along the lines of the early Apollo flightswhere they had these extremely restrictive hardware resources with tiny RAM and CPU abilities and had to manage down to the byte level to get the functionality they needed. I guess with instrumentation it's more like "hell, those big electronics corporations can afford it, just add another $5,000 to the cost. No wackers !"

author: nctnico
author_rank: Super Contributor
timestamp: March 23, 2020, 08:06:58 pm
content: Quote from: edavid on March 23, 2020, 07:59:49 pm8088 rings a loud bell. Thanks! It has been years since I have opened a Tek 2030.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:15:40 pm
content: Wow, stroll down memory lane....This thread reminded me of when I built a Heathkit scope way back when. Anyone remember this?I just saw some drawings for the guts of this and didn't even see any recognizable processor. Heathkit 4105. Dated 1979.

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:35:17 pm
content: Heathkit scopes were 100% analog, the IO-4510 was the last decent scope design to come out of Benton Harbor which was in the early seventies. There where a few later, cheaper models with plastic everything but they never matched the 4510 for performance.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:38:50 pm
content: Oh yeah...analog scope wasn't going to have a processor...DOH !!!And at the time I didn't even know what performance was, so it was all about learning how to solder and what all those parts and the big tube were

author: oPossum
author_rank: Super Contributor
timestamp: March 23, 2020, 08:39:15 pm
content: The Heathkit 4850 was a DSO with a Z80. Could use a CRO for a display.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:42:52 pm
content: Wow, another stroll down memory lane...Z80 reminds me of when I built the Heathkit/Zenith H89 (or was it a Z89?) with a Zilog Z80 CPU. None of this Windows rubbish. Good old Assembly language and Basic.

author: tggzzz
author_rank: Super Contributor
timestamp: March 23, 2020, 08:56:34 pm
content: Quote from: engrguy42 on March 23, 2020, 07:25:23 pmNot necessarily.Hardware engineers are canny, often more so than software engineers. The good ones are focussed on solving their problem, using the most appropriate technology whatever it is labeled.At least one HP protocol analyser' code was Smalltalk, the Digital Smalltalk V variant. That implies it was an 80x86 processor.Some Tektronix products also used Smalltalk. Tek even made some Smalltalk workstations.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 08:59:34 pm
content: Quote from: tggzzz on March 23, 2020, 08:56:34 pmYeah, no kidding...I've often wondered why virtually every bit of software has to go to the users to find all the bugs in seemingly never ending alpha/beta/whatever cycles, but hardware (for the most part) just seems to work.Go figure.

author: nctnico
author_rank: Super Contributor
timestamp: March 23, 2020, 09:09:50 pm
content: Quote from: engrguy42 on March 23, 2020, 08:42:52 pmI'll raise you the Tektronix terminals from the 70's and 80's. No CPU; all discrete logic.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2020, 09:14:46 pm
content: Quote from: engrguy42 on March 23, 2020, 08:02:36 pmAre you saying the Apollo Space Program computers were small because they had a limited budget?PS: The phrase is "No wuckers"(as in "no wucking furries...")

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2020, 09:43:58 pm
content: Quote from: oPossum on March 23, 2020, 08:39:15 pmNever knew they did that one, thanks. It must have right before they went under. One on eBay right now for $80. Was it a complete kit or partially assembled like many of their last products were with the high density digital stuff factory built?

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2020, 09:47:15 pm
content: QuoteAnd the HP9100A RPN calculator in 1968. Not one digital device.

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2020, 09:49:11 pm
content: Quote from: engrguy42 on March 23, 2020, 08:42:52 pmH89 when it was a kit, Z89 when it was pre-built by Zenith.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 09:49:46 pm
content: Too funny. No wuckers.How come we never had that in US???

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 09:53:38 pm
content: Quote from: WattsThat on March 23, 2020, 09:49:11 pmAhhh...okay.I recall spending all day and most of the night soldering parts for that H89 computer (maybe longer...), and maybe 3am I had it all together, flipped on the power switch and sawC>_Beauty...

author: tggzzz
author_rank: Super Contributor
timestamp: March 23, 2020, 10:04:49 pm
content: Quote from: WattsThat on March 23, 2020, 09:47:15 pmExcept, of course, for the DTL and ferrite memory.http://www.vintagecalculators.com/html/hewlett-packard_hp_9100a.html

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 10:25:36 pm
content: Quote from: nctnico on March 23, 2020, 09:09:50 pmOh really?? You want a piece of this?? Huh?Here we go...IBM 360 mainframe with SLT (Solid Logic Technology...okay, I had to look that part up)Punch card readers and writers. Fortran statements, one line per card. You punch one line at a time to a card, then stack them all together in this 2ft long cardboard box, then walk them into the campus computer building and some poor slob loads them into this reader that pulls one card at a time and reads it into memory. And you get a big folded paper output from a monster line printer the next day that says you screwed up a comma in card #443 and you have to do it all over again and wait another day.And don't even get me started on paper tape punches...

author: WattsThat
author_rank: Frequent Contributor
timestamp: March 23, 2020, 10:51:45 pm
content: Quote from: tggzzz on March 23, 2020, 10:04:49 pmWell the “DTL” was built with discreet transistors... yeah, I guess that’s a digital device... with enough base current. I guess I’ve got to be far more specific with my language for all the hair splitters out there. Jeez.engrguy42: Long live unit record equipment. My favorite? The IBM 2560 multi-function card machine. AKA the MFCM, also known as the mother F’er card machine when it destroyed half of your deck of homework FORTRAN 5081’s in a few seconds.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 23, 2020, 10:57:51 pm
content: My Hitachi analog scope used a Z80. My first real DSO is a LeCroy 7200. It has a VME chassis and uses 68000 architecture. They used PSOS.https://en.wikipedia.org/wiki/PSOS_(real-time_operating_system)I later bought a 7200A that is PC based using an Intel processor. That system also uses PSOS. I had given mine away but then a friend of mine sent me another. It needed a little work. You can see what it looks like here.

author: engrguy42
author_rank: Frequent Contributor
timestamp: March 23, 2020, 10:58:24 pm
content: Apologies to the OP for hijacking his thread....I promise I'll behave after this...I recall coming out the the computer building one time and I saw a box of some poor guy's hundreds of Fortran cards lying all scattered in the snow. He was just standing there, almost in tears.All I could say was "wow...dude...that sucks".I can't imagine having to re-sort that mess, or worse yet re-punch them.

author: oPossum
author_rank: Super Contributor
timestamp: March 24, 2020, 12:38:54 am
content: Quote from: WattsThat on March 23, 2020, 09:43:58 pmIt was available as a kit or assembled. There was also a version without the front panel for a little lower cost. It required a computer to operate. The one with the font panel could be used with a CRO for display and/or computer connection.I got one when Heathkit was exiting the kit business in the early 90's. The best feature is the powerup front panel and relay test. It's a craptacular DSO.

author: tggzzz
author_rank: Super Contributor
timestamp: March 24, 2020, 09:17:02 am
content: Quote from: WattsThat on March 23, 2020, 10:51:45 pmExcept, of course, that DTL was the basis for the first large-volume ICs, the Signetics SE100 series and Fairchild 930 serieshttp://www.calcuseum.com/SCRAPBOOK/BONUS/72524/1.htmFerrite memory is also digital

author: David Hess
author_rank: Super Contributor
timestamp: March 24, 2020, 09:32:10 am
content: Quote from: edavid on March 23, 2020, 07:59:49 pmThe 7854 is pretty weird and the changes Tektronix made in the following DSOs show that they learned a lot from it.The Tektronix 468 used an 8085, the 2230 used an 8088, the 2232 used an 80188, and the 2440 series DSOs used a 6805 and 68809. Often custom processors for dedicated tasks like display list rendering and waveform processing are also present.Tektronix had separate design teams for low and high end products but perhaps counter intuitively, the low end products like the 22xx series of 4-channel oscilloscopes often seem more advanced than their contemporary higher end products like the 24xx of series. There does not seem to have been much sharing between the design teams.

author: chris_leyson
author_rank: Super Contributor
timestamp: March 24, 2020, 10:36:12 am
content: HP3585 spectrum analyser used the HP9825 16-bit processor. HP9825 desktop computer software was written in assembler and there are complete listings in some of the HP9825 related patents. Also, the HP9825 has almost identical architecture/instruction set to an early HP2000 series mini computer, HP2114 I think.

author: tggzzz
author_rank: Super Contributor
timestamp: March 24, 2020, 11:15:42 am
content: Quote from: WattsThat on March 23, 2020, 10:51:45 pmThere is also discrete transistor logic that is neither DTL nor RTL - but based on magnetic cores. It was in the first computer that I used, an Elliott 803.http://www.cs.man.ac.uk/CCS/res/res03.htm#eAnd if you want to be obscure, consider that I have a Tektronix test instrument that does divide-by-5 using only 3 transistors. It is discussed in several places on this forum, notablyhttps://www.eevblog.com/forum/repair/tektronix-184-restoration/msg2823978/#msg2823978and intermittently in the monster TEA thread.Even earlier digital memories were made from liquid mercury and CRTs

author: shakalnokturn
author_rank: Super Contributor
timestamp: March 24, 2020, 12:18:27 pm
content: https://www.youtube.com/embed/p7SkE5pERtA

author: PaulAm
author_rank: Frequent Contributor
timestamp: March 24, 2020, 03:48:12 pm
content: QuoteI actually have one of these and it is an incredibly awesome piece of engineering. The program ROM is a board with a zillion diodes. The ferrite is for user program memory and allows program retention over power cycles. There are a few details available on the programming effort to squeeze transcendental functions into it. Absolutely amazing.On some early instruments, HP used a proprietary processor. It's in the 3325a, some of the early LCR meters, some GPIB boards and perhaps some others. It has a very limited instruction set and memory map and had to be programmed in assembly. As a software guy I am impressed by what they managed to squeeze out of it.

author: Fungus
author_rank: Super Contributor
timestamp: March 24, 2020, 04:12:23 pm
content: Quote from: PaulAm on March 24, 2020, 03:48:12 pmA lot of early calculators reduced those diodes into a single chip but they were still hard-wired-logic on the inside, very far from being what most people would class as a microprocessor.eg. I've got a green-screen Casio calculator where you can see the digits on the screen glitching when you press keys and 'clocking' when it computes results. The logic gates inside the ALU are hard wired to the output segments in the display. The screen reflect what's going on inside the chip.(model is CASIO Personal 1)

author: tggzzz
author_rank: Super Contributor
timestamp: March 24, 2020, 04:16:29 pm
content: Quote from: PaulAm on March 24, 2020, 03:48:12 pmAssembler programming was the norm in 70s and first half of the 80s, as were miniscule memories. Consider, for example:http://files.righto.com/calculator/sinclair_scientific_simulator.html

author: TomS_
author_rank: Frequent Contributor
timestamp: March 25, 2020, 11:07:39 am
content: Quote from: engrguy42 on March 23, 2020, 08:59:34 pmUsers won't be able to run the buggy software without working hardware. 😂

author: Howardlong
author_rank: Super Contributor
timestamp: March 25, 2020, 11:27:05 am
content: Quote from: edavid on March 23, 2020, 07:59:49 pmThat was a prime example of tail-wagging-the-dog development if ever I saw it.It’s a trend that continues to this day, trendy developers with something to prove, ignoring all the risks in favour of getting a new line on their resume.

author: tggzzz
author_rank: Super Contributor
timestamp: March 25, 2020, 11:40:13 am
content: Quote from: Howardlong on March 25, 2020, 11:27:05 amI can't comment on the Tek example, but that certainly wasn't true with the HP examples I saw. They worked well, partly due to a careful partitioning between hardware and software, and partly due to an understanding of what the software could and couldn't achieve.QuoteThe trick is to be able to work out which new technology offer something new andbeneficial, as opposed to mere trends offering something new anddifferent.It takes experience and wisdom to be able to do that, which conflicts with many HR-droids views of what makes a good developer.

author: Gyro
author_rank: Super Contributor
timestamp: March 25, 2020, 01:04:51 pm
content: Quote from: edavid on March 23, 2020, 07:59:49 pmThe TMS9900 was a fun CPU choice. It stored all of it's general purpose registers in RAM, so that Subroutines and Interrupt routines could adopt a completely separate register set just by changing the pointer. It also had no Stack in the traditional sense, it just stored the PC for a return.

author: miken
author_rank: Regular Contributor
timestamp: March 29, 2020, 02:21:04 am
content: [Disclosure: I work for Keysight Technologies, formerly Agilent/HP. Opinions are my own.]The firmware for the HP 8568A was written in something colloquially known as WHEELGOL, with calls into assembly routines. The name comes from Lynn Wheelwright, whose Master's Thesis was an ALGOL compiler built on BYU'sTREE-METAsystem. I'm not sure how far forward it was carried, but I suspect all the 68K-based 856x models were on that framework.There's a little article in the June 1978 HP Journal but not many details. The '68A and '66A initially used a custom HP microprocessor, and then the '66B got the 68K.