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11:45 asciilifeform $ticker btc usd
11:45 busybot Current BTC price in USD: $20411.32
~ 54 minutes ~
12:39 phf http://logs.bitdash.io/pest/2022-10-31#1015119 << re this, i'm not sure how this kind of reversing work (my only exposure to it is reading bunnie's xbox hacking book like a decade ago), but besides netlist also need to smh dump the microcode that's embedded in ivory
12:39 bitbot Logged on 2022-10-31 18:32:57 asciilifeform[6]: ( it aint as if photo == netlist, naturally, that -- by hand, sit for yr+... )
12:42 asciilifeform phf: netlist traditionally refers to all the transistors. the microcode tho iirc is actually on the ivory cd, for some unknown reason (tho would still want to see whether same as the iron one)
12:43 phf right, the point was that you get the netlist out by "tracing the datapaths by hand", and it's a different process, conceptually, from "extracting a rom data from a chip"
12:43 asciilifeform afaik thing had no way of loading revised microcode, so nfi why it was distributed with the thing, come to think of it
12:44 asciilifeform extracting microcode tho is 1 of the easier parts of jpg->netlist, as it is arranged in mask rom in grid pattern
12:45 asciilifeform it's errything ~else~ that is 1st class bitch
12:45 phf ah, so you basically see 1 and 0s from the jpegs?
12:45 asciilifeform aha
12:47 asciilifeform example of ucode extraction from (early '80s) ic fwiw.
12:48 phf i've not really studied it in detail, but ivory i take it is just a vlsi take on traditional cadr/3600 "microcode evaluator" architecture
12:49 phf from that perspective the vlm implementation is deceptively more similar to "modern" cpu approach, where each instruction has its dedicated implementation on die, rather than being a microcode vop
12:49 asciilifeform iirc 'ivory' used 'vertical' (i.e. sequences of microinstructions) rather than 'horizontal' (toggles circuits in parallel) microcode, but nfi concretely
12:51 asciilifeform fwiw doc from 'anon informant'(tm) gives recipe for reading ucode via the pins; may be easier than via microscope (or at least to cross-check output of the latter, given as errything ~else~ can only be seen via microscope)
12:52 asciilifeform also allows to read out microcode program counter (step through indiv. uinstructions)
12:54 asciilifeform the macroscopic schema of the thing is in the '87 press release fwiw.
12:55 phf right right, architecture docs seemed to imply that you can put ivory on a bench, bootstrap it pretty much by just bringing it to power, and then inspect rom state using very straightforward programmer style interface
12:55 phf i'm starting to remember things. i feel like i relearn the same facts about ivory every couple of years
12:56 asciilifeform best public photo of the die afaik, ftr.
12:58 phf what's that from?
12:59 asciilifeform phf: was from anuther paper of theirs, can't seem to find the orig locally tho
13:00 phf there's that same basic photo in one of the vlsi conference proceedings that i have, but the quality is much lower
13:02 phf "notes on future implementations of ivory chip" oh sweet summer child
13:03 asciilifeform the photo is prolly of the pre-release die.
13:04 phf there's by the way also http://www.bitsavers.org/pdf/symbolics/Sunstone_Architecture_198711.pdf which was supposed to be next gen, and i don't have any info on except that one pdf
13:05 asciilifeform right, that 1 afaik only existed as marketing lit (and possibly a demo unit or 2, sitting in indiana jones warehouse sumwhere)
13:06 asciilifeform this brochure fwiw had a higher quality scan of the block schem.
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13:11 phf we should bring back measuring things in GIGAWORDs
13:12 asciilifeform indeed (along with, naturally, tagged words, rather than byte-addressed soup)
13:12 phf http://logs.bitdash.io/pest/2022-11-01#1015179 << that is basically your cadr architecture, but on a chip
13:12 bitbot Logged on 2022-11-01 13:06:28 asciilifeform[jonsykkel|deedbot]: this brochure fwiw had a higher quality scan of the block schem.
13:14 asciilifeform well, 3600 was 'cadr on steroids', and 'ivory' -- logical progression, with moar instrs & moarbitness
13:19 asciilifeform the 'ivory in space' piece seems to confirm the 'verticality' of the ucode :
13:19 asciilifeform The first stage fetches
13:19 asciilifeform the instruction, decodes it, and adjusts the program
13:19 asciilifeform counter. The second stage fetches the initial microinstruction, computes the operand address, and adjusts the stack pointer. The third stage fetches the
13:19 asciilifeform operands and computes the result. The fourth stage
13:19 asciilifeform stores the result, unless a fault has occurred, in which
13:19 asciilifeform case it restores the state of the third stage. yy
~ 17 minutes ~
13:37 * asciilifeform back in '19 drew up a test jig pcb for 'ivory', usb <-> fpga <-> 5v buffer <-> zif socket, but not had it baked
~ 30 minutes ~
14:07 phf i suspect the correct method to do an ivory-on-fpga is not to write a microcode evaluator by attempting to reconstruct netlists etc, but to write a compiler from microcode source to spit out verilog
14:09 asciilifeform phf: naturally, if had src, would be 0 reason to bother with micrography etc
14:11 phf i suspect that most recent versions of system don't really leak past micrcode, that is the whole system is expessed in terms of microcode vop, rather than e.g. a mixture of instructions for cpu and vop calls
14:12 asciilifeform possibly only issues explicit uinstrs (appears to be allowed, 1 at a time) if the iron ucode not == to the 1 distributed on disk
14:13 phf right, that's how for example how cadr system did it, a mixture of explicit "uinstrs" and ucode calls
14:17 phf but also like vlm is not a ivory OR 3600 machine emulator, so for all i know they hacked up the compiler so it's a significantly different beast
14:17 * asciilifeform ftr not knows the precise difference b/w the os distributed with the dec/x86 emulator and the macivory's -- possibly this is the key difference
14:22 phf yeah, the vlm documentation is pretty sparse ( i mean in document examiner )
14:22 phf e.g. there's a section for IBIN (obv without details), but not even a mention of VBIN
~ 2 hours 29 minutes ~
16:51 phf completely unrelated question but did anyone (signpost?) try building the absolute minimal framebuffer xorg?
16:52 phf actually no i lied, it's a very much related question. genera talks over network to clx, so i want to build an xorg on a small laptop that doesn't have all the various ((dependencies)). e.g. don't need freetype or of the freedesktop functionality
~ 21 minutes ~
17:14 asciilifeform phf: a while ago asciilifeform built an xorg for rk, but never tested ( couldn't get fb going on that thing )
17:15 asciilifeform not certain it was 'minimal' in the sense described, also ( defo included freetype, sumthing depended on it )
17:16 asciilifeform iirc genera's x11ism is quite compat, even seen to work with crapple's x ( does crapple still include it on the new arm boxen? )
17:17 phf no, separate install, but has been mostly kept up to date
17:17 asciilifeform a
17:17 * asciilifeform at one time used a crapple 'mbp' as an xterm
17:20 phf i'm looking at the xserver sources and it looks like "xquartz" is mainlined
~ 5 hours 5 minutes ~
22:25 asciilifeform phf: does your arm-mac port of the emulator still use x11 for output? or has own fb
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22:26 * asciilifeform would buy that emulator, fair an' square, like bought other dksisms, if were forsale
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