5 ms·

For those not close to the PDP family, the numbers don't really mean anything. The 11 is not better than the 10 in any way, they are just the order in which the

For those not close to the PDP family, the numbers don't really mean anything. The 11 is not better than the 10 in any way, they are just the order in which they were released. The PDP-10 was not a mini-computer for which PDPs are generally associated with, but instead it was a mainframe and had a 36-bit word. The switches were coloured in sets of three to aid in entering octal data (as opposed to hexadecimal).

DonHopkins 2y ago
I've got one of Lars's t-shirts: "IF YOUR COMPUTER DOES NOT HAVE 36 BITS, YOU'RE NOT PLAYING WITH A FULL DEC..." -- attributed to Doug Humphrey (DIGEX) trolling the 32 bit VAX Weenies at DECUS. https://techsquare.myspreadshop.com/36-bit+full+dec-A64fef41b5ad8d84d5016d2ff https://techsquare.myspreadshop.com/36-bit+full+dec-A64fef41... The LMI Lisp Machines Inc. one is quite classy (or rather flavory) too: https://techsquare.myspreadshop.com/lisp+machine+inc-A6417f52e3c63242757ed19e3 https://techsquare.myspreadshop.com/lisp+machine+inc-A6417f5... And a lot more, including Zork, INTERFACE MESSAGE PROCESSOR, decsystem10, digital PDP-10 (also in tie dye!), digital pdp11, IMLAC, GENERAL TURTLE INC., bbn Bolt Beranek and Newman Inc. TENEX, Multics: IF YOU LIKE IT SO MUCH WHY DON'T YOU PUT EIGHT RINGS ON IT, MUDDLE 39 IN OPERATION. LISTENING-AT-LEVEL 1 PROCESS 1, INTERLISP, FOONLY, X Window System Screen Background + X Cursor [wretch!], and more! https://techsquare.myspreadshop.com/all https://techsquare.myspreadshop.com/all I had an even uglier X-Windows t-shirt that I got at the first X11 conference at MIT. It was simply a black and white screen dump with a bunch of incredibly hideous Athena Widgets apps (aka the Anathema Toolkit) like the original X11 netnews and email readers, the infamous butt-ugly xfontsel font selector (for selecting butt-ugly-fonts-with-butt-ugly-logical-font-description-names), and xterm, xlogo, xclock, xcalc, etc, on an audacious lime green background, and I loved to wear it to show off how terrible X-Windows was, and totally wore it out. If anyone still has one I'd pay good money for it! https://en.m.wikipedia.org/wiki/File:Xfontsel.png https://en.m.wikipedia.org/wiki/File:Xfontsel.png https://en.m.wikipedia.org/wiki/X_logical_font_description https://en.m.wikipedia.org/wiki/X_logical_font_description Here's what happens to xcalc if you stretch it around too much -- its layout manager loses its elasticity and begins to look like Donatella Versace after her 10th botched plastic surgery attempt: https://www.donhopkins.com/home/catalog/unix-haters/x-windows/XCalc.gif https://www.donhopkins.com/home/catalog/unix-haters/x-window... To mitigate that problem, I hacked the OLWM window manager so I could run it with a window id parameter to use as the root window, and gave it xcalc's client window id, so it wrapped frames around each of the buttons, and I could drag them around and resize them to repair the damage, make the important ones really big, arrange the digits in any order, and even iconify the buttons I didn't need. But that was even uglier with the OPEN LOOK frames around each button, and was a far cry from HyperCard.
beezle 2y ago
I couldn't find it .. is this running TOPS-10? TOPS-20? Would be nice to have my very own pet TOPS-2060 to use and abuse again! Fond memeories from the early 80s
- nigwil_ 2y ago
  Richard Cornwell's emulator is implemented within the OpenSimH framework, and forms the basis of PiDP-10: https://github.com/rcornwell/sims/tree/master?tab=readme-ov-file#dec-ka10--ki10--kl10--ks10 https://github.com/rcornwell/sims/tree/master?tab=readme-ov-... From the GitHub entry: The KA10 sim has successfully run Tops 10 4.5, 5.03 and 6.03, ITS and WAITS. The KI10 sim has successfully run Tops 10 6.03 with VMSER. The KL10 sim has successfully run Tops 10 6.03-7.03, ITS and Tops 20 V2-V7. The KS10 sim has successfully run Tops 10, Tops 20 and ITS. PiDP-10 can run a variety of PDP-10 operating systems, although the front-panel is specific to the early KA10 model.
skissane 2y ago
> For those not close to the PDP family, the numbers don't really mean anything. The 11 is not better than the 10 in any way, they are just the order in which they were released. Roughly speaking true but not exactly. The PDP-12 and the PDP-14 were both released in 1969 whereas the PDP-11 wasn’t released until 1970. Also, both the PDP-11 and the PDP-15 were released in 1970, but I’m not sure which was released first. Even if it so happens the PDP-11 came out earlier in 1970 than the PDP-15 did, that fact is irrelevant to their numbering.
eschneider 2y ago
Well...the -11 does have a super-clean assembly language. That machine was a joy to work on.
- IndrekR 2y ago
  Used to write MSP430 (a Texas Instruments MCU family that was designed and manufactured in Freising, Germany in ‘90s) assembly language for a while more than two decades ago. It was mentioned with pride that the instruction set is based on PDP-11.
- Pet_Ant 2y ago
  > Well...the -11 does have a super-clean assembly language. Sorry, I meant objectively better in an absolute sense. Just that it's not like the -11 is a sequel to the -10 like a 486 to a 386 is. But you are absolutely right, there are definite strengths of each platform from an enthusiast perspective.
- jhallenworld 2y ago
  Yes but PDP-10 is pretty good: there is only one instruction format, so the instruction set is very uniform. It's, shall we say, delightfully weird in its support of bytes and half-words (addresses). Also: having 256K words is much better than 64 KB.
  - DonHopkins 2y ago
    Arbitrarily sized bytes from 1 to 36 bits, and sub-word byte pointers, and indirect pointers! (You can do a lot with those extra 18 bits above the address lines, it's not just for consing!) https://github.com/PDP-10/documents/blob/master/mirror/www.inwap.com/pdp10/usenet/its-pdp10.info https://github.com/PDP-10/documents/blob/master/mirror/www.i... Byte instructions In the PDP-10 a "byte" is some number of contiguous bits within one word. A byte pointer is a quantity (which occupies a whole word) which describes the location of a byte. There are three parts to the description of a byte: the word (i.e., address) in which the byte occurs, the position of the byte within the word, and the length of the byte. A byte pointer has the following format: 000000 000011 1 1 1111 112222222222333333 012345 678901 2 3 4567 890123456789012345 _________________________________________ | | | | | | | | POS | SIZE |U|I| X | Y | |______|______|_|_|____|__________________| POS is the byte position: the number of bits from the right end of the byte to the right end of the word. SIZE is the byte size in bits. The U field is ignored by the byte instructions. The I, X and Y fields are used, just as in an instruction, to compute an effective address which specifies the location of the word containing the byte. Here are the byte instructions. [...] LDB DPB IBP ILDB IDPB [...] Text strings are typically stored using seven-bit bytes, five per word. ILDB and IDPB can then be used to step through a string. The byte pointer should be initialized to 440700,,<address of string>. Then the first ILDB will increment it to point at the first character of the string.

DonHopkins 2y ago

I've got one of Lars's t-shirts: "IF YOUR COMPUTER DOES NOT HAVE 36 BITS, YOU'RE NOT PLAYING WITH A FULL DEC..." -- attributed to Doug Humphrey (DIGEX) trolling the 32 bit VAX Weenies at DECUS. https://techsquare.myspreadshop.com/36-bit+full+dec-A64fef41b5ad8d84d5016d2ff https://techsquare.myspreadshop.com/36-bit+full+dec-A64fef41... The LMI Lisp Machines Inc. one is quite classy (or rather flavory) too: https://techsquare.myspreadshop.com/lisp+machine+inc-A6417f52e3c63242757ed19e3 https://techsquare.myspreadshop.com/lisp+machine+inc-A6417f5... And a lot more, including Zork, INTERFACE MESSAGE PROCESSOR, decsystem10, digital PDP-10 (also in tie dye!), digital pdp11, IMLAC, GENERAL TURTLE INC., bbn Bolt Beranek and Newman Inc. TENEX, Multics: IF YOU LIKE IT SO MUCH WHY DON'T YOU PUT EIGHT RINGS ON IT, MUDDLE 39 IN OPERATION. LISTENING-AT-LEVEL 1 PROCESS 1, INTERLISP, FOONLY, X Window System Screen Background + X Cursor [wretch!], and more! https://techsquare.myspreadshop.com/all https://techsquare.myspreadshop.com/all I had an even uglier X-Windows t-shirt that I got at the first X11 conference at MIT. It was simply a black and white screen dump with a bunch of incredibly hideous Athena Widgets apps (aka the Anathema Toolkit) like the original X11 netnews and email readers, the infamous butt-ugly xfontsel font selector (for selecting butt-ugly-fonts-with-butt-ugly-logical-font-description-names), and xterm, xlogo, xclock, xcalc, etc, on an audacious lime green background, and I loved to wear it to show off how terrible X-Windows was, and totally wore it out. If anyone still has one I'd pay good money for it! https://en.m.wikipedia.org/wiki/File:Xfontsel.png https://en.m.wikipedia.org/wiki/File:Xfontsel.png https://en.m.wikipedia.org/wiki/X_logical_font_description https://en.m.wikipedia.org/wiki/X_logical_font_description Here's what happens to xcalc if you stretch it around too much -- its layout manager loses its elasticity and begins to look like Donatella Versace after her 10th botched plastic surgery attempt: https://www.donhopkins.com/home/catalog/unix-haters/x-windows/XCalc.gif https://www.donhopkins.com/home/catalog/unix-haters/x-window... To mitigate that problem, I hacked the OLWM window manager so I could run it with a window id parameter to use as the root window, and gave it xcalc's client window id, so it wrapped frames around each of the buttons, and I could drag them around and resize them to repair the damage, make the important ones really big, arrange the digits in any order, and even iconify the buttons I didn't need. But that was even uglier with the OPEN LOOK frames around each button, and was a far cry from HyperCard.

beezle 2y ago

I couldn't find it .. is this running TOPS-10? TOPS-20? Would be nice to have my very own pet TOPS-2060 to use and abuse again! Fond memeories from the early 80s

nigwil_ 2y ago
Richard Cornwell's emulator is implemented within the OpenSimH framework, and forms the basis of PiDP-10: https://github.com/rcornwell/sims/tree/master?tab=readme-ov-file#dec-ka10--ki10--kl10--ks10 https://github.com/rcornwell/sims/tree/master?tab=readme-ov-... From the GitHub entry: The KA10 sim has successfully run Tops 10 4.5, 5.03 and 6.03, ITS and WAITS. The KI10 sim has successfully run Tops 10 6.03 with VMSER. The KL10 sim has successfully run Tops 10 6.03-7.03, ITS and Tops 20 V2-V7. The KS10 sim has successfully run Tops 10, Tops 20 and ITS. PiDP-10 can run a variety of PDP-10 operating systems, although the front-panel is specific to the early KA10 model.

skissane 2y ago

> For those not close to the PDP family, the numbers don't really mean anything. The 11 is not better than the 10 in any way, they are just the order in which they were released. Roughly speaking true but not exactly. The PDP-12 and the PDP-14 were both released in 1969 whereas the PDP-11 wasn’t released until 1970. Also, both the PDP-11 and the PDP-15 were released in 1970, but I’m not sure which was released first. Even if it so happens the PDP-11 came out earlier in 1970 than the PDP-15 did, that fact is irrelevant to their numbering.

eschneider 2y ago

Well...the -11 does have a super-clean assembly language. That machine was a joy to work on.

IndrekR 2y ago
Used to write MSP430 (a Texas Instruments MCU family that was designed and manufactured in Freising, Germany in ‘90s) assembly language for a while more than two decades ago. It was mentioned with pride that the instruction set is based on PDP-11.
Pet_Ant 2y ago
> Well...the -11 does have a super-clean assembly language. Sorry, I meant objectively better in an absolute sense. Just that it's not like the -11 is a sequel to the -10 like a 486 to a 386 is. But you are absolutely right, there are definite strengths of each platform from an enthusiast perspective.
jhallenworld 2y ago
Yes but PDP-10 is pretty good: there is only one instruction format, so the instruction set is very uniform. It's, shall we say, delightfully weird in its support of bytes and half-words (addresses). Also: having 256K words is much better than 64 KB.
- DonHopkins 2y ago
  Arbitrarily sized bytes from 1 to 36 bits, and sub-word byte pointers, and indirect pointers! (You can do a lot with those extra 18 bits above the address lines, it's not just for consing!) https://github.com/PDP-10/documents/blob/master/mirror/www.inwap.com/pdp10/usenet/its-pdp10.info https://github.com/PDP-10/documents/blob/master/mirror/www.i... Byte instructions In the PDP-10 a "byte" is some number of contiguous bits within one word. A byte pointer is a quantity (which occupies a whole word) which describes the location of a byte. There are three parts to the description of a byte: the word (i.e., address) in which the byte occurs, the position of the byte within the word, and the length of the byte. A byte pointer has the following format: 000000 000011 1 1 1111 112222222222333333 012345 678901 2 3 4567 890123456789012345 _________________________________________ | | | | | | | | POS | SIZE |U|I| X | Y | |______|______|_|_|____|__________________| POS is the byte position: the number of bits from the right end of the byte to the right end of the word. SIZE is the byte size in bits. The U field is ignored by the byte instructions. The I, X and Y fields are used, just as in an instruction, to compute an effective address which specifies the location of the word containing the byte. Here are the byte instructions. [...] LDB DPB IBP ILDB IDPB [...] Text strings are typically stored using seven-bit bytes, five per word. ILDB and IDPB can then be used to step through a string. The byte pointer should be initialized to 440700,,<address of string>. Then the first ILDB will increment it to point at the first character of the string.