ChanServ changed the topic of ##yamahasynths to: Channel dedicated to questions and discussion of Yamaha FM Synthesizer internals and corresponding REing. Discussion of synthesis methods similar to the Yamaha line of chips, Sound Blasters + clones, PCM chips like RF5C68, and CD theory of operation are also on-topic. Channel logs: https://freenode.irclog.whitequark.org/~h~yamahasynths
sixtysix_ has quit [Ping timeout: 268 seconds]
<cr1901_modern>
ej5: Do you know of any current runs for Snoot Bopper PCBs?
<ej5>
yeah someone at vogons, there's a thread
<cr1901_modern>
Is it current- as in going on now? Last I checked on vogons, they ran out
andlabs has quit [Quit: My MacBook has gone to sleep. ZZZzzz…]
andlabs has joined ##yamahasynths
andlabs has quit [Quit: My MacBook has gone to sleep. ZZZzzz…]
andlabs has joined ##yamahasynths
andlabs has quit [Read error: Connection reset by peer]
andlabs has joined ##yamahasynths
<Lord_Nightmare>
whitequark: when i get the keyboard, i'll desolder the main mcu and the ym2413 and send just those, and i guess scrap the rest, although if mad or plgdavid need parts i guess i can send those...
<Lord_Nightmare>
not sure
<whitequark>
Lord_Nightmare: ack
<cr1901_modern>
It'd be nice if plgdavid logged onto IRC more than once a year :(
<Lord_Nightmare>
main mcu iirc is an sdip64 HD6301X0 or HD6301Y0, i forget, i'll have to check the service manual if i can find a copy
<Lord_Nightmare>
the eprom hd63701X0 and Y0 both have documented dumping modes, but iirc the mask ROM hd6301X0 and Y0 might not...
<Lord_Nightmare>
i know its possible to run them in external ROM mode at least
<Lord_Nightmare>
by messing the the mode pins
<Lord_Nightmare>
let me ask kevtris, he did some work on this a while ago
<Lord_Nightmare>
why he isn't in here, i'm not sure
<Lord_Nightmare>
(iirc he may have too many channels open in his irc client)
<cr1901_modern>
Lord_Nightmare: >iirc he may have too many channels open in his irc client
<cr1901_modern>
Correct, not enough activity here to dedicate to a tab
<cr1901_modern>
He explicitly said he was open to returning if activity picked up/someone needed his feedback
<cr1901_modern>
which I mean, fine w/ me :P
<cr1901_modern>
(that being said, I haven't heard a peep from him in months. Last I talked to him, his Genesis core just came out)
<Lord_Nightmare>
i poked him in PM, he's around
<cr1901_modern>
Thanks wq for exposing me to that abomination of a connector again :)
<Lord_Nightmare>
i hope that's not real
<Lord_Nightmare>
i'm praying that its not real
<Lord_Nightmare>
honestly the din-5 connector with the embedded usb micro in the middle of it is actually not a terrible design
<Lord_Nightmare>
since if the usb micro is standard size, you can plug a micro cable in to it
<Lord_Nightmare>
or a din-5
<Lord_Nightmare>
or a 'combo connector' which is both din-5 AND usb
<ej5>
is that my stupid fake din5+micro usb connector rendering?
<cr1901_modern>
ej5: Maaaaaaybe :)
<ej5>
XD like half the people think it's serious and the other half get it
<cr1901_modern>
I don't really care if it's real or fake, it burns my retinas either way :)
<ej5>
lol
<Wohali>
it's not real :D
<Wohali>
lolol
<cr1901_modern>
it doesn't matter it's not real :). I'm still scarred
<cr1901_modern>
I will be filing a def not frivolous lawsuit in the near future
<Lord_Nightmare>
ej5 if you'd stuck the usb micro tangent to the side rather than perpendicular, it might make slightly more sense
<Lord_Nightmare>
it would still be a huge pain in the ass to use regardless :P
<ej5>
yeah that would have been a bit too subtle, too many people would have believed it
<whitequark>
lol
<whitequark>
but if you stuck it at a tangent it'd actually be worse
<whitequark>
because you don't want to route out the USB contacts to the PCB at a 90° angle
<whitequark>
i guess multirow USB connectors do this anyway
<whitequark>
never seen a multirow USB C though
<whitequark>
only A
<TD-Linux>
D+ and D- on the two unused pins
<whitequark>
horrifying, and probably not impedance matched
<Lord_Nightmare>
whitequark: if you stuck it BELOW the din5 connector but flat against the pcb (i.e. where the din5 key tab is) it would still line up properly with the pcb
<Lord_Nightmare>
if it is a right angle mount
<whitequark>
oh
<whitequark>
point
<Lord_Nightmare>
from a cable usability and reliability standpoint it makes the most sense to stick it in the middle of the connector though, right 'above' the key tab
<Lord_Nightmare>
as long as the usb connector is the same exact length as the key slot bit and the 5 pins, it shouldn't* be easy to accidentally snap it off
<Lord_Nightmare>
* this sort of assumption is problematic, since if you make something idiot proof the world will always provide a better idiot
<Lord_Nightmare>
someone will inevitably try to plug it into an older device, see it doesn't fit and snap the usb part off with pliers
<Lord_Nightmare>
cvsd stuff: based on datasheets from harris and the application note, my guess is one of the sf=0.4ms se=1ms VS sf=4ms se=1ms is correct, and the other is wrong, and the wrong one was just copied from datasheet to datasheet
<Lord_Nightmare>
se=1ms means a ~160hz cutoff, first order, which seems awfully low for the final filter
<Lord_Nightmare>
I've seen greefkes described in literature as the 'inventor' of CVSD but i'm not sure that's technically true, it sounds like a lot of people were working on this same problem in the late 60s/early 70s
<Lord_Nightmare>
jayant's digital system (which is almost exactly how i suspect the hc55516 works, except jayant's example uses 2 bits, and hc55516 uses 3, while mc3418 uses 4) uses a IIR multiplier of the previous sample, a 1-tap 1 pole filter
<Lord_Nightmare>
with two constants, one for the overload case and one for the normal case
<Lord_Nightmare>
let me see if i can dig up the actual references cited there, 39 (jayant) and 41,25 (cummiskey)...