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
<andlabs> could be a timing issue
<andlabs> who knows
<andlabs> here's the blogpost about atgames audio, btw
<andlabs> IDK how it was fixed at the emulator level; this only fixes it per-ROM
<natarii> opn2 output rate is clock/144 iirc
<ValleyBell> On the MegaDrive the YM2612 has a clock of 7670454 Hz and a sample rate of 53267 Hz.
<andlabs> I forget, is the YM2612 output digital?
<cr1901_modern> no
<cr1901_modern> It's TDM analog
<cr1901_modern> some of the chips add up all the channels internally before outputting data
<andlabs> in that case why talk about sample rate at all
<cr1901_modern> because the output is sampled. It's an analog value that changes only at discrete time steps
<cr1901_modern> And TDM's frequency domain looks similar to if you summed up all channels before emitting a sample.
<cr1901_modern> Sarayan gave a good explanation of this a while back in the channel
<cr1901_modern> (caveat: I had to leave before he finished it)
<andlabs> hm
<andlabs> also yay the PSU always-on adapters finally arrived I should now FIANLLY have everyhting I need to run fluxengine
<andlabs> though with my luck there'll probably be yet another part I need next
l_oliveira has joined ##yamahasynths
<andlabs> and just my luck, I think the molex -> floppy connectors I got are junk, because ther'es definitely power going into the molex connector but the floppy drive won't turn on
<andlabs> oh well, I can at least try the 5.25" drive now that I have some blank disks
<andlabs> it made a sound!
<andlabs> ugh the floppy drive is working and responding to me inserting a disk but it won't interface with the fluxengine arggggggggggggggh
<andlabs> oh wait it thinks the fluxengine isn't plugged in for some reason
<andlabs> okay NOW it's refusing to interface with the drive
<andlabs> should the disk drive keep spinning repatedly until I close the latch? that seems wrong; no indicator light so it's not the cable
<andlabs> aha, if I insert the disk upside down, the drive doesn't stop even with the latch down, and I hear a constant clicking
<andlabs> I still have zeor idea what htis means; I never used 5.25" disks when I was young
<andlabs> ah, now I see the light coming on, so yes, me flipping the cable is working as expected; I bet I have the drive itself upside down
<andlabs> doesn't explain why the clicking still happens even the right way around
<ValleyBell> How can you even insert the disk the wrong way?
<ValleyBell> It has this small square that is cut on the right side.
<andlabs> because it's supposed to be able to read DSDD disks too
<ValleyBell> The drive in the KC-85/3 here won't even let you pull the lever down all the way when the disk is inserted incorrectly.
<ValleyBell> ah, okay
<andlabs> either way that still doesn't explain the clicking
<andlabs> and the constnat spinning while the latch is up
<andlabs> I think the head is making contact with the media
<andlabs> when my replacement phone comes I can make a video
<ValleyBell> The drive doing noise without a disk inserted doesn't sound all that unfamiliar to me.
<ValleyBell> I can't test it right now though, because there is too much stuff lying in that corner of my room.
<whitequark> andlabs: so with the 3.5" drives there's an optocoupler that stops the motor if there's no disk
<whitequark> but, iirc, there's no such thing on (all? most?) 5.25" drives
<andlabs> no, this is with the disk
<andlabs> once I insert the disk fully and close the latch, the drive spins forever and clicks
<andlabs> the light only goes on if the cable is backwards; this happens regardless of cable orientation
<andlabs> hey Foone
<andlabs> thanks for finding that discman program
<andlabs> I had ripped out its demo ebook to use in a test that I'm going to be using with a real data dsicman disc instead once this last PSU comes in
<andlabs> will need to figure out how to open one fo those caddies that'll be fun
<Nerionaya> what on earth, why did I think that the PC Engine Duo R couldn't play audio CDs
<andlabs> ^ oh, and what I'm looking at might not work with what that person just mentioned, for dumb reasons
<andlabs> with something related to it
<cr1901_modern> ej5: My current impression of EGA is that it's "A CGA-like-but-not-reg compatible CRT controller with extra support ICs (and registers!) to make programming more pleasant"
<ej5> yeah the CRTC is...weird
<ej5> i spent the morning digging through them to figure out the video timings. not sure why i bothered lol
<cr1901_modern> it has the same index-reg/data-reg layout of the 6845, but I don't think the fields are compatble
<cr1901_modern> The support ICs have the same index-reg/data-reg layout as well.
<cr1901_modern> when you write the bit-pattern 0xff to 0xa000:0x0000, you're actually writing 4 bits of data to eight pixel locations
<cr1901_modern> You can set up one of the ICs so a write of the bit-pattern 0xff instead writes e.g. 3 bits of data (bit planes 0, 1, 2. Or bit planes 1, 2, 3. Or 0, 1, 2. etc)
<cr1901_modern> Point blank, a write to a single bit in EGA memory can actually write up to 4 bits of memory on the card
<cr1901_modern> I haven't figured out how to get a 64-color palette yet. The gfx mode I'm using seems to imply your color choice is fixed
<cr1901_modern> (4 colors if you don't have > 128kB of memory, 16 colors otherwise)