I see - I would have guessed quite a few more instructions than that, based on my PDP-11 experience (my 8/L has only paper tape).
The PDP-12, which I have more experience at, takes about the same amount of effort/time, but just the one I/O instruction in the switch register (but then you have to enter the start address, and start the machine). On 8/6/2015 4:03 PM, Johnny Billquist wrote: > On 2015-08-06 23:00, Jay Jaeger wrote: >> I should think that a set of manually entered bootstrap instructions >> (i.e., not on a diode ROM board) would take considerably longer than >> 5s. ;) > > You might think so. But when you see the bootstrap for the RK05 on a > PDP-8, you realize that it takes about 5s to toggle it in and run it. > > It's only two 12-bit words that you need to write after all... > > In short: > 0030 LOAD ADDRESS > 6743 DEP > 5031 DEP > 0030 LOAD ADDDRESS > START > > When you've done it a few times, you get fairly proficient at it, and > it's not hard to remember... Even faster on a PDP-8/A which have a > numeric keypad frontpanel. > > Johnny > >> >> On 8/6/2015 1:43 PM, Johnny Billquist wrote: >>> PDP-8 with OS/8 on an RK05. From power up until booted and ready was >>> basically the time for the disk to spin up, which was about 10 seconds. >>> The actual booting of the system is about 0.3 seconds. Add 5 seconds if >>> you had to manually enter the bootstrap. >>> >>> Johnny >>> >>> On 2015-08-06 20:43, Jay Jaeger wrote: >>>> Acch. All this modern/complicated stuff. Once you powered on an IBM >>>> 1410 (2 seconds), you could have it (141O O/S: 1410-PR-155) running in >>>> as little as a minute, counting the tape drive mount: >>>> >>>> Mount tape on unit 0 [30 seconds tops, as tape is probably already >>>> there] >>>> Storage Scan to +1 >>>> Sense switches to a blank character >>>> [The above two were normally left that way] >>>> Mode switch to CE >>>> Computer Reset >>>> Start >>>> 00000 [This clears storage] >>>> Computer Reset >>>> Move Mode Switch to Display >>>> Start >>>> 00000 [Display before altering] >>>> Press margin release on console typewriter while it types out "bbbbb" >>>> Computer Reset >>>> Move Mode Switch to Alter >>>> 00000 >>>> A(WM)L%B000012$(WM)N [Read tape to end of core/record to loc 12] >>>> Computer Reset >>>> Start >>>> [Wait about 10 seconds for 1410-PR-155 to load] >>>> >>>> :) >>>> >>>> >>>> >>>> On 8/6/2015 1:21 PM, Fred Cisin wrote: >>>>>>> Wow. I'll never complain again that it takes too long to boot >>>>>>> Windows... >>>>> >>>>> On Thu, 6 Aug 2015, geneb wrote: >>>>>> One thing I don't understand - why can't the machine boot on its own? >>>>>> Why would IBM design a computer that required another computer >>>>>> just to >>>>>> boot it? >>>>> >>>>> "Why CAN'T the operating system have full functionality during >>>>> booting?" >>>>> I had an interesting conversation almost 30 years ago with a published >>>>> expert on operating systemes and C programming, when he was >>>>> bothered by >>>>> why IO.SYS/IBMBIO.COM and DOS.SYS/IBMDOS.COM had to be in specific >>>>> places on the drive. >>>>> >>>>> "Booting" is of course short for "bootstrapping", which is a >>>>> multi-hundred year old term for a obviously ridiculously impossible >>>>> task: "pulling yourself up by your bootstraps". >>>>> I had always thought that that derived from Baron Von Munchausen, >>>>> but a little research turns up that the baron had lifted himself >>>>> and his horse out of the swamp by his pigtail, not his bootstraps. >>>>> It wasn't until early 1800s that "bootstrapping" became the iconic >>>>> example. >>>>> >>>>> The reason that IPL is called "booting" is because it is such an >>>>> obviously ridiculously impossible task. >>>>> "You can't use the operating system to load the operating system." >>>>> >>>>> Obviously it is simplest if somebody (or machine) outside, loads >>>>> the code into memory, and then triggers a GOTO. >>>>> Which is cheaper, or more reliable, a "trained" operator, or a >>>>> smaller external machine? >>>>> >>>>> The really clever way, though, was to toggle in, or have a little ROM, >>>>> to load a TINY bit of stored code ("boot sector") into RAM, GOTO it, >>>>> and it could contain enough code to load a bigger chunk, which could >>>>> have plenty of code to load the rest. >>>>> >>>>> >>>>> Why not just put the OS in ROM? >>>>> That would require more ROM, would make bug-fixes more difficult, >>>>> and would make it more difficult to modify the OS to add new >>>>> features, such as security holes. >>>>> >>>>> >>>>> >>>>> >>> >>> > >