And thusly were the wise words spake by Brent Hilpert You are supposed to forget about static RAM and dynamic RAM 'cause those were not too terribly important in the whole stream of computing evolution.. What *is* important is flash memory! Jus' like core mem it keeps its thoughts even when the power is off... That is the modern computin' connection missin' link! :P Cheers, Bryan

I don't mind it all that much...EXCEPT... (1) I don't trust them to get the "write the new one then switch" logic right to avoid trashing things in case of power-offs while writing. (2) I *really* dislike systems that do this without having a hardware facility to disable writes - such as a pair of jumper pins which must be jumpered to write. (If software can do it, rogue software can do it.) /~\ The ASCII der Mouse \ / Ribbon Campaign X Against HTML mouse at rodents.montreal.qc.ca / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B

Jules Richardson wrote: One would think so, yes? Pat Finnegan helped me revive an IBM 43P-260 awhile back - arguably workstation-class, but well into my idea of "a real computer". It had a version mismatch between the service processor's firmware and the main system firmware, probably due to a hosed firmware update. This completely bricks the system - no boot, no recovery option, nada. you can talk to the service processor, but the SP's firmware flash option requires that the system boot. Catch 22. IBM's supported repair option was to replace the entire I/O planar, where the service processor's EEPROM lives. The I/O board is about 2/3 of the system's logic, with the "system board" being basically a CPU/RAM backplane. Doc

On Friday 12 October 2007 15:02, woodelf wrote: Speaking of which, I have a tube or so of 2816s around, and would appreciate it if you guys could point me toward any materials on the 'net that'd give me some ideas as to how you use those things... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

Datasheetarchive is your friend :o) http://www.datasheets.org.uk/search.php?t=0&q=2816&manystr=&sub…

On Friday 12 October 2007 16:27, Chuck Guzis wrote: Does that stuff have a limit in terms of how many times you can write to it, like some of the earlier choices did? I did look at a bit of data on those parts, but didn't get the answer to that one out of it... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

Chuck Guzis wrote: I still can't find the unlimited writes bit. But with at a few GHZ a jillion is not that long.[1] Ben. [1] Used for default windows display. This way win/2'13 can crash[2] and you still can type away. [2]It does that now... automatic updates force a reboot anywhere from 30 seconds to 3 hours later.

Intel's phase change memory is supposed to be unlimited cycles and a 30 year storage time. I don't think core had the 30 year limitation. The Ramtron 5 volt parts had a cycle limit but the 3.3 volt parts are supposed to be unlimited. At work, we have been testing a 3.3 volt part, running a simple memory test at 150ns cycles for over 6 months with no errors (yet). Bob "Roy J. Tellason" <rtellason at verizon.net> wrote: On Friday 12 October 2007 16:27, Chuck Guzis wrote: Does that stuff have a limit in terms of how many times you can write to it, like some of the earlier choices did? I did look at a bit of data on those parts, but didn't get the answer to that one out of it... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

On Fri, 12 Oct 2007 11:21:23 -0700, Brent Hilpert wrote: Many years ago, when removing magnetic core from process control systems I was required to erase well more like scramble the magnetic core before it could leave the plant. So there was no chance process variables would leave the plant. I would take off the top cover and pass a magnet over the core array and told them to put it back into the system, if they did not believe me, but I had no idea what state the production line would come back up in, if at all. Never had anyone put one back in and test it. One of the sales points of using magnetic core memory on early process control systems even as late as the early 8080 days, was core's ability to retain state on loss of power. One of the leading process control systems of the day did not boot as we know it today on power up It just woke back up, the program was always stored in 16k of magnetic core. The floppy drive was an FE tool for IMPL of core on cold boot. Power on was a true warm boot because the current program was still in memory in a running state. It just needed to be restarted or continued depending on the first interupts it gets back from it's sensors. Not to defend the person who wrote #10 above, but is not instant on, fast recover to operation, computing devices based on rewriteable static memory, the very definition of modern computing even if they only had a clock speed of 476khz. These words being typed by someone who just flashed an ATT/Cingiular 8525 2gigs of storage and 3G connectivity. The Other Bob Still a few Bobs short of a choir :)

And thusly were the wise words spake by dwight elvey Speaking of the quartz crystal, when did the first one(s) (approximately) come out? Cheers, Bryan

Bryan Pope wrote: In the context of classic computing I'm guessing you're asking about crystal controlled oscillators? The first use of a quartz piezoid to control the frequency of an oscillator circuit is generally credited to Cady in 1919. The more familiar Pierce oscillator dates to 1923. -- Chris Kennedy chris at mainecoon.com AF6AP http://www.mainecoon.com PGP KeyID 108DAB97 PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97 "Mr. McKittrick, after careful consideration..."

dwight elvey wrote: (No doubt that core was important, just the way it was attributed in the photo blurb was misleading). I quite agree about the 4004. It may have been first, but it was one of those things whose time had come - it really wasn't that big a conceptual leap. Some time ago I ran across an editorial in a magazine ca. 1969 that basically summed up the problem: increasing logic density and hence IC complexity (LSI was on the horizon) would result in an explosion of chip designs that would be unmanageable (unique design per task,low production runs,etc.). The answer a year or two later would be the microproc (few chip designs, uniqueness in software in ROM). You could say FPGA/CPLDs are another, more recent, answer to that question. Now if only I could find that editorial. Based on what I've read though, I disagree about the (degree of) credit generally given to TI/Kilby regarding the creation of the IC, on similar grounds: in the late 50s there were lots of efforts/attempts/designs to create miniature modules of some sort. Kilby made the 'obvious' (like the microproc) development of not cutting the transistor dies apart from the wafer before interconnecting them and got to the patent office first on that issue. His techniques however, were frankly a bit of a hack that weren't going to go (scale up) anywhere. It was the development of the planar form of transistor by Hoerni, junction isolation by Lehovec and putting it all together with various layering techniques by Noyce at Fairchild that created and made feasible the IC as we still know it today. Can't testify to it's accuracy but one of my favorite quips about the 4004 is the reason it had that multiplexed 4-bit bus/machine cycle was to squish it into a 16-pin package because management didn't want to tool up for larger packages.

Chuck Guzis wrote: Can't remember where I read it, but it seemed plausible for the time the 4004 was being developed (1970), also that it was compounded by management's perceptions that the 4004 was a little business on the side and not willing to invest much in it, memory chips still being the focus. On the other hand, I wonder what packages the original Busicom designs utilised - that Intel would otherwise have been obligated to produce - one would expect, or typically, they would be larger. (The 4040 would go to a larger package, of course.) Perhaps not speed as an issue but you were wired into the small family of chips that understood the highly specific machine/bus cycle, at least until the 4008/9 came along that broke out the address/data busses.

Hi The 4040 was just an expanded 4004. It had more addressing range. It was used in the universal prom programmer. Each personality card would have the electronics to program a specific part and a couple 4001 ROM chips to handle I/O and specific code. These were but interface chips that took the pmos levels and convertered then to TTL levels to use with standard RAM, ROM, EPROM and I/O. They included the needed mux decoders and the needed instruction monitors to know when to read or write onto the bus. These two were replaced later by a single chip ( 42?? ) that did the same fuctions. The 4004 family included: 4004 CPU 4001 ROM I/O 4002 RAM Output 4003 Shift reg output 4008/9 Interface and a couple others I forget. Dwight _________________________________________________________________ Help yourself to FREE treats served up daily at the Messenger Caf?. Stop by today. http://www.cafemessenger.com/info/info_sweetstuff2.html?ocid=TXT_TAGLM_OctW…

Fred Cisin wrote: That would be the 5005 :)

On Saturday 13 October 2007 15:40, dwight elvey wrote: Oh, heck, I'd forgotten about PMOS stuff altogether! :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

"Ethan Dicks" <ethan.dicks at gmail.com> wrote: NMOS is good at pulling down. This works well with TTL with a pullup resistor, because TTL traditionally is a "pull down" logic family. The NMOS output pins are not by any means beefy - usually they only are good for driving a single TTL or two inputs, and only with the right pullups. Some NMOS chips used on-chip pullups (I think actually weak PMOS FETS on the chip but I was NEVER a VLSI guy.) PMOS is good at pulling up. This is not a natural match to TTL. NMOS is only compatible if the supplies are structured to be similar to the TTL levels. PMOS often used voltages that were rather bizarre compared to the TTL designer's view of 0 and +5V, because there was almost always some extra interface glue between the two. For fun, abandon gates and instead build stuff out of CD4007's. The datasheets and part number might make you think it's a logic chip, but in real life it's some NMOS/PMOS pairs with a good amount of the internal connections available. Lotsa fun as an analog device! And now that the CA3046 is discontinued I may as well learn how to use FET's :-). Tim.

On 10/13/07, Brent Hilpert <hilpert at cs.ubc.ca> wrote: There's some stuff in Don Lancaster's "CMOS Cookbook" about the CD4007. Quite interesting to read about. -ethan

Hi The instruction width is 8 bits so that matches. It is just the data that is 4 bits. There are a number of 4 bit RAMs out there. If you use the 4008/9 chips, you can used regular EPROMs and static RAMs. No need to be upset at not having 4001's or 4002's. Of course you'll need to memory map your I/O. I don't recall if the 4008/4009 did I/O separately but it might. I don't think the board in my development system used a 4201. It seems it just use a few transistors. Dwight _________________________________________________________________ Peek-a-boo FREE Tricks & Treats for You! http://www.reallivemoms.com?ocid=TXT_TAGHM&loc=us

dwight elvey wrote: The only gotya I can guess might be timing delay between clock phases.

dwight elvey wrote: Oh, I have built a plug-in 4201 replacement from 3 4000-series CMOS ICs, so the equipment is functional (it's just kind of ugly - a daughter board connected via a 16-pin DIP plug). The clock cycle used is modulo-7 so it's not quite trivial. One might question the drive capability of the CMOS but it seems to work well enough, I think when I did it I looked at the phases on the 'scope and they appeared as sharp as with an actual 4201.

---snip---> > - RAM: no provision it appears, so you still need a 4002 > (or get by with registers, or via I/O) Hi It looks like one would need to build a full bus monitor. One would no longer need the 4008/9 since one could use the same circuit to moitor all. The way the ROM and RAM chips work is that they watch the instructions on the bus, going to the processor. When they see instructions that require specific actions, they then execute that operation on the bus. As an example, if they see a write to RAM, the RAM chip sees the instruction and then does the write at the correct timing cycle. One can use the circuitry used for the EPROM on the SIM4-01 as an example of how to monitor the instruction flow. With some extra work, one doesn't need 4002s. They do show up on ebay now and then. Do remember, there are two types. There are 4002-1s and 4002-2s The enable is inverted so these can be used on the same select line. Dwight _________________________________________________________________ Windows Live Hotmail and Microsoft Office Outlook ? together at last. ?Get it now. http://office.microsoft.com/en-us/outlook/HA102225181033.aspx?pid=CL1006269…

"Roy J. Tellason" wrote: A poor scan of some datasheets are (were?) at http://smithsonianchips.si.edu/ice/4004thb.htm I know there are some others scans out there as well although I have yet to run across a good set. In brief, initially the main chips of the family were: 4001: 256*8 ROM & 4-bit IO 4002: 320-bit RAM & 4-bit IO 4004: 4-bit CPU In a system a 4-bit bus along with a few timing/sync signals interconnected a 4004 and multiples of the 4001/2. Address and data were muxed through the bus in a somewhat complex sequence. The 4001/2s were hard-programmed with address range and I/O port numbers to respond to. The 4008 & 9 were introduced later, and were in larger packages, they demuxed the bus/machine cycle into wider,separate address/data lines to permit use of more-conventional RAM/ROM/EPROM chips and easier I/O. The mask-programmed 4001/2 made it all essentially inaccessible to hobbyists but the small packages and high level of family integration actually did make for very compact systems. Regarding the 4040, I'm speculating as I've never dealt with one or come across the pinout, but I suspect the 4040 essentially integrated the 4004/4008/4009 into one larger package making it look more like a 'standard' microproc in terms of signals/interface (somebody correct me if I'm wrong).

dwight elvey wrote: Thanks for the correction, but why was it in such a larger package? (4040 was a 28 or 40-pin package wasn't it?).

On Oct 13, 2007, at 8:03 PM, woodelf wrote: Really? I've never heard about that. What was the problem with larger packages, do you recall? -Dave -- Dave McGuire Port Charlotte, FL Farewell Ophelia, 9/22/1991 - 7/25/2007

Brent Hilpert wrote: All I can say is try to find the real data sheet. Ben. Pinouts here http://intelvsamd.info/Intel_4040.html Instruction set http://www.pastraiser.com/ PS. I don't see anything under bitsavers/intel

dwight elvey wrote: Thanks, that matches up with the pinout Ben found. Along with some other contribs it appears the 4040 was mostly software-arena improvements with relatively little change to the hardware/interface environment.

On Saturday 13 October 2007 10:46, dwight elvey wrote: I've often wondered why it is that 14-pin packages seemed to dominate the early parts so much. Why they never offered, for example, a dual 2-input gate package instead of the more common quad, or other combinations like that. It seemed sometimes that things were altered a bit to fit into those 14-pin packages that they wanted to use... And I don't lay any claim to having any kind of a clue about what factors dominated the economics of things back then. :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

On Saturday 13 October 2007 15:56, Brent Hilpert wrote: I was just thinking more along the lines of when you only need some of what's in a typical package... And what's funny is that there now seems to be some stuff out there that's offering as simple as single gates in a small surface-mount package. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

On Saturday 13 October 2007 19:50, William Donzelli wrote: I've never heard of these nor seen any reference to them. How did they number those parts? Sounds like it might make a worthwhile addition to the parts pages... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

^^^^^ Wow, great grasp of the English language, Will... -- Will (sorry)

On Sunday 14 October 2007 16:06, William Donzelli wrote: Oh. Well, in that case... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

I've never seen thosei in any databooks, do you have the part numbers? I do remember 7545x parts that were dual 2-input gates with open collector outputs that could drive lamps/relays/etc. IIRC AND, NAND, OR, NOR gates all existed The only 8-pin TTL chips I (just) rememebr the 7456 ands 7457 (I think) which were /50 and /60 counters (desigend to get 1Hz clocks from European or US power lines) -tony

I prefer mechanical horology, but anyway (actually, there have been mechanical digital clocks, but I digress). It's not that hard to provide the same fucntion using a pair of 7490s or a 7490 + 7492 as approrpritate. Or to start from a wristwatch crystal (32768Hz) and use a 15 stage divider. I've never seen either. -tony

On Sunday 14 October 2007 16:07, Tony Duell wrote: Yes, and I've managed to scrape up data on those. If I'm not mistaken, that dual floppy drive in the Cromemco we were talking about a bit ago uses a bunch of those in there. (Looking...) Yup, here in the "299B Disk Drive" manual I spot some 75453 and 75454 in several locations in there. Those always struck me as extremely handy parts, I wonder if they're still commonly available? Those were LS56 and 57, or at least that's what's in my parts page, if there were earlier non-LS versions of them I haven't found any data on them. I don't recall ever actually running across those, but do remember some other part number that was a similar package size and functionality. And speaking of 50 and 60 Hz, I have this digital clock here that I got *real* cheap, because it has a problem. it gains a LOT of time every hour. Something like 10 minutes, maybe? I'm convinced that it's jumpered (or something) for 50 Hz line power. :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

think) Europe= got=20 ho= (or=20 When I need / needed 50 / 60 Hz I use / used a Mostek 5009 ( 16 pins ). Yes I have a datasheet. I think I have a couple parts in my Mostek dark archives... Best regards, Steven C

Motorola has a whole line. You can find it on farnell, digikey, mouser, and all good electronic suppliers :o)

Ethan Dicks said: [...] Unnecessary. They are rather common, Farnell, Digikey etc. should have them. Google for 74LVC1G00 for a single 7400 type NAND, for instance. The series is labeled "1G", basically. Consequently, there should be also 02, 04, 08, 32, and 86 gates. -- Holger

Roy J. Tellason wrote: There was a company started up in the 1971 or 1972 time frame in Columbia, Missouri that made a splash in the IC market by offering "cheap" parts. It was Solid State Industries, or SSI and sold a pretty good mix of 7400 IC's. They bought the die and packaged them in Columbia. The big cost was the packaging machine at the time. That is to some degree what dictated their choices of what to package, since they eliminated the actual silicon fab from their business model. They kept up for a while but eventually were wiped out the eventual drop of prices to a few cents. Jim

Roger Pugh wrote: You need to own more things with azerty keyboards.

Tony Duell wrote: Time for touchscreens? Else maybe a hangar. Steve

Roy J. Tellason wrote: There were keyboards with little lcd "screens" on the keycaps. You download whatever you wanted to it.

On Sunday 14 October 2007 22:01, Doc Shipley wrote: So, was he? :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

Doc Shipley wrote: Was she cute? Peace... Sridhar

any sources for "Megalodork" T-shirts?

On Mon, 22 Oct 2007, woodelf wrote: You rang?

--- Roger Pugh <rogpugh at mac.com> wrote: Well, that's not as bad as all that. It's only when you get to the point where computers start substituting for furniture that you should worry. Sparcstation end tables, IBM nightstand, that sort of thing. -Ian

And thusly were the wise words spake by Roger Pugh Does it keep the food warm too? :) Cheers, Bryan

It takes a long time to cook over a Pentium I.

On 14 Oct 2007 at 17:05, Fred Cisin wrote: An old friend who worked on SAGE said the operators used to store their lunches inside the machine. Mmmm, toasty... Cheers, Chuck

Rumor has it that Alexandre Souza may have mentioned these words: Ahh.... too much information! ;-) http://www.amazon.com/Manifold-Destiny-Guide-Cooking-Engine/dp/0375751408 If you ever wanna go "Emeril" with your engine...... Laterz, Roger "Merch" Merchberger -- Roger "Merch" Merchberger -- SysAdmin, Iceberg Computers zmerch at 30below.com What do you do when Life gives you lemons, and you don't *like* lemonade?????????????

On Saturday 13 October 2007 16:01, jim s wrote: I may have even heard of them somewhere along the line, though I'm not certain. Interesting bit of history there. I remember that drop, I used to look at the ads in the back of magazines like Popular Electronics and such, where something like a 7400 went from a couple of dollars down and down and down, eventually getting to the point of around 10 cents or so for one. And then LSTTL came into the picture and complicated the heck out of things, and they've been getting more so ever since then. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin

On 12 Oct 2007 at 23:02, Brent Hilpert wrote: Check old Datamation and Computerweek issues; I used to read those religiously and that may be where I saw it. Could also have been in an IEEE publication. That was the definitely the buzz in 1969-70; I remember commenting to an EE prof at a local university that the single-chip monolithic CPU was just on the horizon. His reaction was one who was being told that blue M&Ms were just on the horizon. He just didn't get it. When I left CDC for the grand world of microprocessors, Neil Lincoln (the architect of the not-yet-envisioned ETA-10) had me flown to Arden Hills to talk some sense into me. After spending most of a day tagging around with him being shown the great projects on the drawing board, he sat down and said: "So you're leaving supercomputers for MICROCOMPUTERS? Really?" I told him that I'd seen the future and he confessed that he'd just bought a Commodore Pet. I told him that I'd had an MITS Altair since 1975. Cheers, Chuck

On 13 Oct 2007 at 7:46, dwight elvey wrote: That's interesting, particularly considering the competition at the time, the Rockwell PPS-4 in the funny quad-row package. We need to be fair, though--none of these (4004, 8008, PPS-4) were single-chip microprocessors--they all required additional support logic chips that, it could be argued, were just as much a part of the microprocessor as what was in the main package. The act of moving the control and sequencing into the same package as the ALU doesn't seem like that much of a leap in retrospect. I've even seen the National IMP-16 referred to as a microprocessor in some documents; that was definitely a multi-chip configuration. Something you could simply connect a crystal and some RAM to was still in the future. On 13 Oct 2007 at 2:14, Brent Hilpert wrote: One of the more humiliating memories of mine was stopping by my apartment with a (female) co-worker and showing her my just-assembled new pride and joy; the MITS Altair. This would have been 1975. Her response was something to the effect of "I thought you told me you had a computer. THAT'S not a computer; that's a toy with blinking lights. You paid a thousand dollars for THAT?" What is it that H.L. Mencken said? "How little it takes to make life unbearable: a pebble in the shoe, a cockroach in the spaghetti, a woman's laugh." I was mortified. Cheers, Chuck

Brent Hilpert wrote: Another area that I frequent is vintage pinball machines. The PPS-4 was widely used in another embedded controller design for Gottlieb(Chicago) in their first generation digital pinball machines. Although it wasn't the first digital pinball in the market, their first digital pinball using this design was released in 1977, well after the PPS-4 became obsolete, until 1980. Sadly though, it has become uneconomical for most pinball collectors to get these CPU boards repaired and instead use a replacement board which emulates the embedded software. =Dan [ "I do not fear computers. I fear the lack of them" ] [ Pittsburgh --- http://www2.applegate.org/~ragooman/ ]

William Donzelli wrote: It's not sad in all respects, just some, because there's collectors which still like to own the original hardware that operated the machines, much like us computer collectors. I would still rebuild these occasionally for those die hard collectors. But for the average buyer, they don't mind what's inside as long as it plays. =Dan [ "I do not fear computers. I fear the lack of them" ] [ Pittsburgh --- http://www2.applegate.org/~ragooman/ ]

Dan Roganti wrote: As it happens, those Gottlieb boards are the task I was working on: trying to get enough details about the chips to create an exerciser for the boards for use in servicing them. Was working on it last winter, I hope to get back to it this winter. I have no knowledge of the pinball arena though, it's purely a technical task to me.

Brent Hilpert wrote: Yeah, I'd wondered that too - there was all sorts going on around that sort of time; TI went down one route, but I don't think they were "first IC", just "first IC using a particular approach". (I always get wary when people use the filing of a patent as the definitive proof that someone was first to do something :-) Oh, someone mentioned the IMP-16 - mine happened to be nearby; there's six 'major' ICs on the (approx 12" x 9") board (plus a couple of EPROMs on mine, a handful of TTL, and 16 1101 chips - RAM, I'd assume). cheers Jules