On 14/08/20 08:27, Tauno Voipio wrote:> On 14.8.20 9.00, Tom Gardner wrote: >> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>> ... >>>> The 1802 wasn't too odd, except that the PC was designated >>>> by a 4-bit register under programmer control. >>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>> and direct octal code input. >>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>> >>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>> was surprised when I mentioned having used it :) >>> >>> The first computer I used was an Elliott 803, at Bangor University, with 8k >>> words (it had a second cabinet for the additional 4k). We ran Algol with it >>> which was loaded from paper tape, a 6" diameter roll. The run time library >>> was on a second slightly smaller roll of tape and had to be loaded with the >>> executable from the compiler. >>> >>> That machine had a 39-bit word, and used a serial architecture running at >>> ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. >> >> I used one while was in the 6th form, in the neighbouring Ewell >> Tech (now NESCOT). >> >> I'm not sure whether they loaded Algol from the paper tape, since >> it also had the (sprocketed) magnetic film devices. >> >> The instruction cycle time was 276us. >> >> I almost went to Bangor, but Southampton was more convenient. >> >> If you are ever near TNMoC, go and see one working, and listen >> to it playing music (the high notes are very flat!). When I >> mentioned I was an electronic engineers and had used one, >> they whipped out the schematics and we discussed them. >> >> Now that's what I call a /good/ museum. By comparison, Bletchley >> Park next door is a bog-standard museum only worth seeing once. >> > > The basic cycle was 288 us, and most instructions used two cycles, > 576 us. IIRC, the only single-cycle instructions were control transfers. > > There were two instructions in a 39 bit word, 6 instruction code bits > and 13 address bits for 19 bits per instruction. The extra bit in > the instruction word was an address modifier bit: If it was on, the > address of the second part was indexed with the result of the first > part before use.Ach, the 276 was a typo on my part; I remember it being a 2kIPS machine, i.e. 576us. I don't think I was aware of the 288us timing. ISTR I used the instruction modifier bit in my hand-assembled program. That converted from one 5 channel paper tape code we had at my school to the Elliott 5 channel code. (ASCII was wonderful :) ) I forget the details, but it had two "states" (for fig/num shift) and a computed goto based on the next character read. Someone else tried to do it with if-the-elses, and failed miserably. Although I didn't realise it at the time, that taught me that /thinking/ and working out the right abstraction makes things much more tractable. Youngsters don't seem to realise that, and just use whatever they've been taught.
Is there a good book for learning about valves/tubes?
Started by ●August 9, 2020
Reply by ●August 14, 20202020-08-14
Reply by ●August 14, 20202020-08-14
In article <PLpZG.808392$f44.746840@fx09.am4>, spamjunk@blueyonder.co.uk says...> > On 14/08/20 00:54, ke...@kjwdesigns.com wrote: > > On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: > > ... > >> The 1802 wasn't too odd, except that the PC was designated > >> by a 4-bit register under programmer control. > >>> I agree on Hoare's Algol. It was a huge step forward from Autocode > >>> and direct octal code input. > >> I did both, trimphantly reinventing a simple FSM in the latter case :) > >> > >> The Algol compiler fitted in 4Kwords. I met Hoare once, and he > >> was surprised when I mentioned having used it :) > > > > The first computer I used was an Elliott 803, at Bangor University, with 8k words (it had a second cabinet for the additional 4k). We ran Algol with it which was loaded from paper tape, a 6" diameter roll. The run time library was on a second slightly smaller roll of tape and had to be loaded with the executable from the compiler. > > > > That machine had a 39-bit word, and used a serial architecture running at ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. > > I used one while was in the 6th form, in the neighbouring Ewell > Tech (now NESCOT). > > I'm not sure whether they loaded Algol from the paper tape, since > it also had the (sprocketed) magnetic film devices. > > The instruction cycle time was 276us. > > I almost went to Bangor, but Southampton was more convenient. > > If you are ever near TNMoC, go and see one working, and listen > to it playing music (the high notes are very flat!). When I > mentioned I was an electronic engineers and had used one, > they whipped out the schematics and we discussed them. > > Now that's what I call a /good/ museum. By comparison, Bletchley > Park next door is a bog-standard museum only worth seeing once.I was going to comment that the audio speed of the 803 meant that listening to it run on the speaker was a useful diagnostic tool. If the burble changed tone or stopped, something had happened! This was on the one in the maths department of WCAT (which became UWIST) in Cardiff. Agreed about TNMoC too. Not sure I saw their 803, but did discuss a device they have which used Dekatrons, since I used them for counting in a student project I made in the early 1960s. I donated some valves and my late Dad's valve tester, since they ran a valve exchange scheme. I also contributed a display board showing the antecedent companies to my then employer International Computers Limited. Deeply boring! Mike.
Reply by ●August 14, 20202020-08-14
On 14/08/20 10:03, Mike Coon wrote:> In article <PLpZG.808392$f44.746840@fx09.am4>, spamjunk@blueyonder.co.uk > says... >> >> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>> ... >>>> The 1802 wasn't too odd, except that the PC was designated >>>> by a 4-bit register under programmer control. >>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>> and direct octal code input. >>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>> >>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>> was surprised when I mentioned having used it :) >>> >>> The first computer I used was an Elliott 803, at Bangor University, with 8k words (it had a second cabinet for the additional 4k). We ran Algol with it which was loaded from paper tape, a 6" diameter roll. The run time library was on a second slightly smaller roll of tape and had to be loaded with the executable from the compiler. >>> >>> That machine had a 39-bit word, and used a serial architecture running at ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. >> >> I used one while was in the 6th form, in the neighbouring Ewell >> Tech (now NESCOT). >> >> I'm not sure whether they loaded Algol from the paper tape, since >> it also had the (sprocketed) magnetic film devices. >> >> The instruction cycle time was 276us. >> >> I almost went to Bangor, but Southampton was more convenient. >> >> If you are ever near TNMoC, go and see one working, and listen >> to it playing music (the high notes are very flat!). When I >> mentioned I was an electronic engineers and had used one, >> they whipped out the schematics and we discussed them. >> >> Now that's what I call a /good/ museum. By comparison, Bletchley >> Park next door is a bog-standard museum only worth seeing once. > > I was going to comment that the audio speed of the 803 meant that > listening to it run on the speaker was a useful diagnostic tool. If the > burble changed tone or stopped, something had happened! This was on the > one in the maths department of WCAT (which became UWIST) in Cardiff.Somewhere I have a cassette tape I made as a schoolkid. "Fetch Algol" sounded lie a broody hen.> Agreed about TNMoC too. Not sure I saw their 803, but did discuss a > device they have which used Dekatrons, since I used them for counting in > a student project I made in the early 1960s. I donated some valves and > my late Dad's valve tester, since they ran a valve exchange scheme. I > also contributed a display board showing the antecedent companies to my > then employer International Computers Limited. Deeply boring!The WITCH is the oldest operating computer in the world. The 803 is in the same room as the ICL290x, next door to the WITCH. Simply because dekatrons are fun, I recently bought a dekatron counter without the associated geiger tube. The knob on the front panel sets the tube voltage to 200-350V(?), and that is accessible to fingers on the front panel connector. Touch that, and it counts at 50Hz. It is moderately entertaining to have someone watching as you measure the voltage before touching it.
Reply by ●August 14, 20202020-08-14
On 14.8.20 10.47, Tom Gardner wrote:> On 14/08/20 08:27, Tauno Voipio wrote: >> On 14.8.20 9.00, Tom Gardner wrote: >>> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>>> ... >>>>> The 1802 wasn't too odd, except that the PC was designated >>>>> by a 4-bit register under programmer control. >>>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>>> and direct octal code input. >>>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>>> >>>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>>> was surprised when I mentioned having used it :) >>>> >>>> The first computer I used was an Elliott 803, at Bangor University, >>>> with 8k words (it had a second cabinet for the additional 4k). We >>>> ran Algol with it which was loaded from paper tape, a 6" diameter >>>> roll. The run time library was on a second slightly smaller roll of >>>> tape and had to be loaded with the executable from the compiler. >>>> >>>> That machine had a 39-bit word, and used a serial architecture >>>> running at ~145kHz clock rate, with OC45 transistors giving about >>>> 0.003 Mips IIRC. >>> >>> I used one while was in the 6th form, in the neighbouring Ewell >>> Tech (now NESCOT). >>> >>> I'm not sure whether they loaded Algol from the paper tape, since >>> it also had the (sprocketed) magnetic film devices. >>> >>> The instruction cycle time was 276us. >>> >>> I almost went to Bangor, but Southampton was more convenient. >>> >>> If you are ever near TNMoC, go and see one working, and listen >>> to it playing music (the high notes are very flat!). When I >>> mentioned I was an electronic engineers and had used one, >>> they whipped out the schematics and we discussed them. >>> >>> Now that's what I call a /good/ museum. By comparison, Bletchley >>> Park next door is a bog-standard museum only worth seeing once. >>> >> >> The basic cycle was 288 us, and most instructions used two cycles, >> 576 us. IIRC, the only single-cycle instructions were control transfers. >> >> There were two instructions in a 39 bit word, 6 instruction code bits >> and 13 address bits for 19 bits per instruction. The extra bit in >> the instruction word was an address modifier bit: If it was on, the >> address of the second part was indexed with the result of the first >> part before use. > > Ach, the 276 was a typo on my part; I remember it being > a 2kIPS machine, i.e. 576us. I don't think I was aware > of the 288us timing. > > ISTR I used the instruction modifier bit in my hand-assembled > program. That converted from one 5 channel paper tape code > we had at my school to the Elliott 5 channel code. (ASCII was > wonderful :) ) > > I forget the details, but it had two "states" (for fig/num shift) > and a computed goto based on the next character read. Someone else > tried to do it with if-the-elses, and failed miserably. > > Although I didn't realise it at the time, that taught me that > /thinking/ and working out the right abstraction makes things > much more tractable. > > Youngsters don't seem to realise that, and just use whatever > they've been taught.The 5-bit + case code was picked from the Telex teleprinter network, but for some reason Elliott decided to use differenc character codes. One of the early programming challenges was to make a tape that would have letters and figures correct even when read backwards. I agree on ASCII. -- -TV
Reply by ●August 14, 20202020-08-14
On 14.8.20 12.03, Mike Coon wrote:> In article <PLpZG.808392$f44.746840@fx09.am4>, spamjunk@blueyonder.co.uk > says... >> >> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>> ... >>>> The 1802 wasn't too odd, except that the PC was designated >>>> by a 4-bit register under programmer control. >>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>> and direct octal code input. >>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>> >>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>> was surprised when I mentioned having used it :) >>> >>> The first computer I used was an Elliott 803, at Bangor University, with 8k words (it had a second cabinet for the additional 4k). We ran Algol with it which was loaded from paper tape, a 6" diameter roll. The run time library was on a second slightly smaller roll of tape and had to be loaded with the executable from the compiler. >>> >>> That machine had a 39-bit word, and used a serial architecture running at ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. >> >> I used one while was in the 6th form, in the neighbouring Ewell >> Tech (now NESCOT). >> >> I'm not sure whether they loaded Algol from the paper tape, since >> it also had the (sprocketed) magnetic film devices. >> >> The instruction cycle time was 276us. >> >> I almost went to Bangor, but Southampton was more convenient. >> >> If you are ever near TNMoC, go and see one working, and listen >> to it playing music (the high notes are very flat!). When I >> mentioned I was an electronic engineers and had used one, >> they whipped out the schematics and we discussed them. >> >> Now that's what I call a /good/ museum. By comparison, Bletchley >> Park next door is a bog-standard museum only worth seeing once. > > I was going to comment that the audio speed of the 803 meant that > listening to it run on the speaker was a useful diagnostic tool. If the > burble changed tone or stopped, something had happened! This was on the > one in the maths department of WCAT (which became UWIST) in Cardiff. > > Agreed about TNMoC too. Not sure I saw their 803, but did discuss a > device they have which used Dekatrons, since I used them for counting in > a student project I made in the early 1960s. I donated some valves and > my late Dad's valve tester, since they ran a valve exchange scheme. I > also contributed a display board showing the antecedent companies to my > then employer International Computers Limited. Deeply boring! > > Mike. >The audio of the 803 came from the most significant bit of the instruction regiater. The high-pitched whine of a dynamic stop was the 288us cycle of a jump to self. -- -TV
Reply by ●August 14, 20202020-08-14
On 14/08/20 13:45, Tauno Voipio wrote:> On 14.8.20 10.47, Tom Gardner wrote: >> On 14/08/20 08:27, Tauno Voipio wrote: >>> On 14.8.20 9.00, Tom Gardner wrote: >>>> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>>>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>>>> ... >>>>>> The 1802 wasn't too odd, except that the PC was designated >>>>>> by a 4-bit register under programmer control. >>>>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>>>> and direct octal code input. >>>>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>>>> >>>>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>>>> was surprised when I mentioned having used it :) >>>>> >>>>> The first computer I used was an Elliott 803, at Bangor University, with 8k >>>>> words (it had a second cabinet for the additional 4k). We ran Algol with it >>>>> which was loaded from paper tape, a 6" diameter roll. The run time library >>>>> was on a second slightly smaller roll of tape and had to be loaded with the >>>>> executable from the compiler. >>>>> >>>>> That machine had a 39-bit word, and used a serial architecture running at >>>>> ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. >>>> >>>> I used one while was in the 6th form, in the neighbouring Ewell >>>> Tech (now NESCOT). >>>> >>>> I'm not sure whether they loaded Algol from the paper tape, since >>>> it also had the (sprocketed) magnetic film devices. >>>> >>>> The instruction cycle time was 276us. >>>> >>>> I almost went to Bangor, but Southampton was more convenient. >>>> >>>> If you are ever near TNMoC, go and see one working, and listen >>>> to it playing music (the high notes are very flat!). When I >>>> mentioned I was an electronic engineers and had used one, >>>> they whipped out the schematics and we discussed them. >>>> >>>> Now that's what I call a /good/ museum. By comparison, Bletchley >>>> Park next door is a bog-standard museum only worth seeing once. >>>> >>> >>> The basic cycle was 288 us, and most instructions used two cycles, >>> 576 us. IIRC, the only single-cycle instructions were control transfers. >>> >>> There were two instructions in a 39 bit word, 6 instruction code bits >>> and 13 address bits for 19 bits per instruction. The extra bit in >>> the instruction word was an address modifier bit: If it was on, the >>> address of the second part was indexed with the result of the first >>> part before use. >> >> Ach, the 276 was a typo on my part; I remember it being >> a 2kIPS machine, i.e. 576us. I don't think I was aware >> of the 288us timing. >> >> ISTR I used the instruction modifier bit in my hand-assembled >> program. That converted from one 5 channel paper tape code >> we had at my school to the Elliott 5 channel code. (ASCII was >> wonderful :) ) >> >> I forget the details, but it had two "states" (for fig/num shift) >> and a computed goto based on the next character read. Someone else >> tried to do it with if-the-elses, and failed miserably. >> >> Although I didn't realise it at the time, that taught me that >> /thinking/ and working out the right abstraction makes things >> much more tractable. >> >> Youngsters don't seem to realise that, and just use whatever >> they've been taught. > > The 5-bit + case code was picked from the Telex teleprinter network, > but for some reason Elliott decided to use differenc character codes. > > One of the early programming challenges was to make a tape that would > have letters and figures correct even when read backwards. > > I agree on ASCII.I thought letter-shift and figure-shift had been consigned to the dustbin of history - and good riddance. Now youngsters use it all the time, with another shift thrown in for good^h^h^h^h bad measure :(
Reply by ●August 14, 20202020-08-14
On 2020-08-14 08:55, Tom Gardner wrote:> On 14/08/20 13:45, Tauno Voipio wrote: >> On 14.8.20 10.47, Tom Gardner wrote: >>> On 14/08/20 08:27, Tauno Voipio wrote: >>>> On 14.8.20 9.00, Tom Gardner wrote: >>>>> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>>>>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>>>>> ... >>>>>>> The 1802 wasn't too odd, except that the PC was designated >>>>>>> by a 4-bit register under programmer control. >>>>>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>>>>> and direct octal code input. >>>>>>> I did both, trimphantly reinventing a simple FSM in the latter >>>>>>> case :) >>>>>>> >>>>>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>>>>> was surprised when I mentioned having used it :) >>>>>> >>>>>> The first computer I used was an Elliott 803, at Bangor >>>>>> University, with 8k words (it had a second cabinet for the >>>>>> additional 4k). We ran Algol with it which was loaded from paper >>>>>> tape, a 6" diameter roll. The run time library was on a second >>>>>> slightly smaller roll of tape and had to be loaded with the >>>>>> executable from the compiler. >>>>>> >>>>>> That machine had a 39-bit word, and used a serial architecture >>>>>> running at ~145kHz clock rate, with OC45 transistors giving about >>>>>> 0.003 Mips IIRC. >>>>> >>>>> I used one while was in the 6th form, in the neighbouring Ewell >>>>> Tech (now NESCOT). >>>>> >>>>> I'm not sure whether they loaded Algol from the paper tape, since >>>>> it also had the (sprocketed) magnetic film devices. >>>>> >>>>> The instruction cycle time was 276us. >>>>> >>>>> I almost went to Bangor, but Southampton was more convenient. >>>>> >>>>> If you are ever near TNMoC, go and see one working, and listen >>>>> to it playing music (the high notes are very flat!). When I >>>>> mentioned I was an electronic engineers and had used one, >>>>> they whipped out the schematics and we discussed them. >>>>> >>>>> Now that's what I call a /good/ museum. By comparison, Bletchley >>>>> Park next door is a bog-standard museum only worth seeing once. >>>>> >>>> >>>> The basic cycle was 288 us, and most instructions used two cycles, >>>> 576 us. IIRC, the only single-cycle instructions were control >>>> transfers. >>>> >>>> There were two instructions in a 39 bit word, 6 instruction code bits >>>> and 13 address bits for 19 bits per instruction. The extra bit in >>>> the instruction word was an address modifier bit: If it was on, the >>>> address of the second part was indexed with the result of the first >>>> part before use. >>> >>> Ach, the 276 was a typo on my part; I remember it being >>> a 2kIPS machine, i.e. 576us. I don't think I was aware >>> of the 288us timing. >>> >>> ISTR I used the instruction modifier bit in my hand-assembled >>> program. That converted from one 5 channel paper tape code >>> we had at my school to the Elliott 5 channel code. (ASCII was >>> wonderful :) ) >>> >>> I forget the details, but it had two "states" (for fig/num shift) >>> and a computed goto based on the next character read. Someone else >>> tried to do it with if-the-elses, and failed miserably. >>> >>> Although I didn't realise it at the time, that taught me that >>> /thinking/ and working out the right abstraction makes things >>> much more tractable. >>> >>> Youngsters don't seem to realise that, and just use whatever >>> they've been taught. >> >> The 5-bit + case code was picked from the Telex teleprinter network, >> but for some reason Elliott decided to use differenc character codes. >> >> One of the early programming challenges was to make a tape that would >> have letters and figures correct even when read backwards. >> >> I agree on ASCII. > > I thought letter-shift and figure-shift had been consigned to > the dustbin of history - and good riddance. > > Now youngsters use it all the time, with another shift thrown > in for good^h^h^h^h bad measure :(Well, we all grew up with crystal-clear full duplex phones as well. How did they get us to settle for these ridiculous walkie-talkie things? When organizing a phone meeting I'm constantly having to nudge people to use land lines. Otherwise there's a strong likelihood that some loquacious individual will monopolize it--usually adding long ahhhhhs while deciding what to say next, to prevent people from interrupting. Dunno if it's deliberate, but I expect it sometimes is. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●August 14, 20202020-08-14
On 14/08/20 14:12, Phil Hobbs wrote:> On 2020-08-14 08:55, Tom Gardner wrote: >> On 14/08/20 13:45, Tauno Voipio wrote: >>> On 14.8.20 10.47, Tom Gardner wrote: >>>> On 14/08/20 08:27, Tauno Voipio wrote: >>>>> On 14.8.20 9.00, Tom Gardner wrote: >>>>>> On 14/08/20 00:54, ke...@kjwdesigns.com wrote: >>>>>>> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >>>>>>> ... >>>>>>>> The 1802 wasn't too odd, except that the PC was designated >>>>>>>> by a 4-bit register under programmer control. >>>>>>>>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>>>>>>>> and direct octal code input. >>>>>>>> I did both, trimphantly reinventing a simple FSM in the latter case :) >>>>>>>> >>>>>>>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>>>>>>> was surprised when I mentioned having used it :) >>>>>>> >>>>>>> The first computer I used was an Elliott 803, at Bangor University, with >>>>>>> 8k words (it had a second cabinet for the additional 4k). We ran Algol >>>>>>> with it which was loaded from paper tape, a 6" diameter roll. The run >>>>>>> time library was on a second slightly smaller roll of tape and had to be >>>>>>> loaded with the executable from the compiler. >>>>>>> >>>>>>> That machine had a 39-bit word, and used a serial architecture running at >>>>>>> ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC. >>>>>> >>>>>> I used one while was in the 6th form, in the neighbouring Ewell >>>>>> Tech (now NESCOT). >>>>>> >>>>>> I'm not sure whether they loaded Algol from the paper tape, since >>>>>> it also had the (sprocketed) magnetic film devices. >>>>>> >>>>>> The instruction cycle time was 276us. >>>>>> >>>>>> I almost went to Bangor, but Southampton was more convenient. >>>>>> >>>>>> If you are ever near TNMoC, go and see one working, and listen >>>>>> to it playing music (the high notes are very flat!). When I >>>>>> mentioned I was an electronic engineers and had used one, >>>>>> they whipped out the schematics and we discussed them. >>>>>> >>>>>> Now that's what I call a /good/ museum. By comparison, Bletchley >>>>>> Park next door is a bog-standard museum only worth seeing once. >>>>>> >>>>> >>>>> The basic cycle was 288 us, and most instructions used two cycles, >>>>> 576 us. IIRC, the only single-cycle instructions were control transfers. >>>>> >>>>> There were two instructions in a 39 bit word, 6 instruction code bits >>>>> and 13 address bits for 19 bits per instruction. The extra bit in >>>>> the instruction word was an address modifier bit: If it was on, the >>>>> address of the second part was indexed with the result of the first >>>>> part before use. >>>> >>>> Ach, the 276 was a typo on my part; I remember it being >>>> a 2kIPS machine, i.e. 576us. I don't think I was aware >>>> of the 288us timing. >>>> >>>> ISTR I used the instruction modifier bit in my hand-assembled >>>> program. That converted from one 5 channel paper tape code >>>> we had at my school to the Elliott 5 channel code. (ASCII was >>>> wonderful :) ) >>>> >>>> I forget the details, but it had two "states" (for fig/num shift) >>>> and a computed goto based on the next character read. Someone else >>>> tried to do it with if-the-elses, and failed miserably. >>>> >>>> Although I didn't realise it at the time, that taught me that >>>> /thinking/ and working out the right abstraction makes things >>>> much more tractable. >>>> >>>> Youngsters don't seem to realise that, and just use whatever >>>> they've been taught. >>> >>> The 5-bit + case code was picked from the Telex teleprinter network, >>> but for some reason Elliott decided to use differenc character codes. >>> >>> One of the early programming challenges was to make a tape that would >>> have letters and figures correct even when read backwards. >>> >>> I agree on ASCII. >> >> I thought letter-shift and figure-shift had been consigned to >> the dustbin of history - and good riddance. >> >> Now youngsters use it all the time, with another shift thrown >> in for good^h^h^h^h bad measure :( > > Well, we all grew up with crystal-clear full duplex phones as well. How did > they get us to settle for these ridiculous walkie-talkie things?What I can't stand is the quality of the music my (now departed) daughter plays through it. I always loathed the tinny "transistor radio" sound when growing up; this is worse. Curiously I might find it relaxing to hear one type of "music": the sounds of a waterfall or a cloudburst in the Amazon rain forest. The latter is famously synthesised by the percussionist Nana Vasconcelos. He gets the audience to clap randomly, slowly at first, then faster, then more slowly. I once watched a professional percussionist, Dame Evelyn Glennie, see that. Her jaw /literally/ dropped and flapped around.> When organizing a phone meeting I'm constantly having to nudge people to use > land lines. Otherwise there's a strong likelihood that some loquacious > individual will monopolize it--usually adding long ahhhhhs while deciding what > to say next, to prevent people from interrupting. Dunno if it's deliberate, but > I expect it sometimes is.When I had such intercontinental events discussing 60GHz systems, everything seemed to go smoothly. Didn't bother with video, but did share X-desktops. I don't know how modern multiparty Zoom parties work.
Reply by ●August 14, 20202020-08-14
Am 14.08.20 um 01:54 schrieb ke...@kjwdesigns.com:> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: > ... >> The 1802 wasn't too odd, except that the PC was designated >> by a 4-bit register under programmer control. >>> I agree on Hoare's Algol. It was a huge step forward from Autocode >>> and direct octal code input. >> I did both, trimphantly reinventing a simple FSM in the latter case :) >> >> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >> was surprised when I mentioned having used it :) > > The first computer I used was an Elliott 803, at Bangor University, with 8k words (it had a second cabinet for the additional 4k). We ran Algol with it which was loaded from paper tape, a 6" diameter roll. The run time library was on a second slightly smaller roll of tape and had to be loaded with the executable from the compiler. > > That machine had a 39-bit word, and used a serial architecture running at ~145kHz clock rate, with OC45 transistors giving about 0.003 Mips IIRC."My" first machine was a Telefunken TR4, the first commercial micro-programmed machine ever. It was withdrawn from military service and donated to the univ. AEG-Telefunken always was somewhat distinctive, Teak wood panels everywhere and they paid their engineers above average, sort of an aristocratic company. When Daimler-Mercedes bought them, that was quickly rectified & they were soon a me-too company. The TR4 had 48 bit registers with a neon lamp for each bit. Mostly OC604 / AC122 / 151 / AC157. < https://upload.wikimedia.org/wikipedia/commons/5/53/Telefunken-tr4.jpg > Disk drives were Boroughs(?) with > 1m diameter, a 3phase motor and a leather belt between the platters and the motor. And each track had a head of it's own. But it was able to compile Spice 2G4. In a certain sense this was my first PC. Operators worked it from 9 to 5 and some of us EE students were allowed to run it for the rest of the time. Sometimes I missed the last train to my home town an hour past midnight. :-) Cheers, Gerhard
Reply by ●August 14, 20202020-08-14
On 2020-08-14 09:59, Gerhard Hoffmann wrote:> Am 14.08.20 um 01:54 schrieb ke...@kjwdesigns.com: >> On Thursday, 13 August 2020 at 13:59:08 UTC-7, Tom Gardner wrote: >> ... >>> The 1802 wasn't too odd, except that the PC was designated by a >>> 4-bit register under programmer control. >>>> I agree on Hoare's Algol. It was a huge step forward from >>>> Autocode and direct octal code input. >>> I did both, trimphantly reinventing a simple FSM in the latter >>> case :) >>> >>> The Algol compiler fitted in 4Kwords. I met Hoare once, and he >>> was surprised when I mentioned having used it :) >> >> The first computer I used was an Elliott 803, at Bangor University, >> with 8k words (it had a second cabinet for the additional 4k). We >> ran Algol with it which was loaded from paper tape, a 6" diameter >> roll. The run time library was on a second slightly smaller roll of >> tape and had to be loaded with the executable from the compiler. >> >> That machine had a 39-bit word, and used a serial architecture >> running at ~145kHz clock rate, with OC45 transistors giving about >> 0.003 Mips IIRC. > > "My" first machine was a Telefunken TR4, the first commercial > micro-programmed machine ever.Wiki says the EDSAC 2 (fully operational in 1958) was microprogrammed.> It was withdrawn from military service and donated to the univ. > AEG-Telefunken always was somewhat distinctive, Teak wood panels > everywhere and they paid their engineers above average, sort of an > aristocratic company. When Daimler-Mercedes bought them, that was > quickly rectified & they were soon a me-too company. > > The TR4 had 48 bit registers with a neon lamp for each bit. Mostly > OC604 / AC122 / 151 / AC157. > > < > https://upload.wikimedia.org/wikipedia/commons/5/53/Telefunken-tr4.jpg > > > > Disk drives were Boroughs(?) with > 1m diameter, a 3phase motor and a > leather belt between the platters and the motor. And each track had a > head of it's own. > > But it was able to compile Spice 2G4. > > In a certain sense this was my first PC. Operators worked it from 9 > to 5 and some of us EE students were allowed to run it for the rest > of the time. Sometimes I missed the last train to my home town an > hour past midnight. :-)I had a car when I went to university (if you call it that--it was a Fiat 128 with an 1100 cc engine) so I didn't miss any trains, but I did spend some nights in the terminal room hunched over a green glowing 3270 trying to get this Danish observatory's radiative transfer code running. Good times--teaching myself Fortran while debugging somebody else's code that simulated physics I didn't yet understand. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
