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
<Lord_Nightmare>
ej5: that hp hard drive, i'm assuming its an HPFS variant
<ej5>
doesn't seem to be, it's actually FAT16 with the byte order reversed
<Lord_Nightmare>
you may want to talk to philpem about it, he wrote some modifications to the HPFS linux kernel module to be able to mount HPFS images from PA-RISC systems
<ej5>
the 1670 doesn't run hpux, it runs pSOS apparently
<Lord_Nightmare>
PA-RISC HPFS is "V2" and is big endian, unlike "V3" which the linux kernel module supports
<Lord_Nightmare>
fixing the kernel module to be aware of the endian differences between the filesystem versions was a nightmare, if i remember what philpem told me eariler
<Lord_Nightmare>
I don't think his patches were ever merged upstream either
<Lord_Nightmare>
hmm. i wonder if that hard disk format is "v1"? or maybe not...
<Lord_Nightmare>
if you swap every byte pair on the entire disk around, does it mount correctly as fat16?
<Lord_Nightmare>
if so, then that seems pretty easy to deal with
<Lord_Nightmare>
the PA-RISC V2 HPFS stuff is used, iirc, on the 16505 and 16700 logic analyzers
<Lord_Nightmare>
as well as some PA-RISC separate machines
<ej5>
looks like the partition table isn't 100% standard
<ej5>
anyway yeah it won't mount as FAT but the partition table has a string "FAT16" and there does appear to be FAT16 tables, but they're slightly...odd
<ej5>
OEM name in the MBR is "HP16500B"
<balrog>
ej5: hmm do the restore disks for these exist anywhere?
<balrog>
and yeah, 1670 is a scaled down (non-slot) version of the 16500 series; 16505 was the HP-UX "prototype analyzer" add-on for the 16500 series
<balrog>
on these, the suffix letter designates generation
<ej5>
yes E
<ricky26>
I just read the Mega Drive manual for the YM2612 and I think my head is going to explode.
<Lord_Nightmare>
don't read the sega sega2.doc/sega02.doc thing (aka "GenesisSoftwareManual.pdf" or similar, since it has an absolutely ridiculous number of errors in it
<Lord_Nightmare>
including numbering the operators wrong
<Lord_Nightmare>
this incorrect numbering is also used in Sega Technical Institute's "GEMS" music engine/editor
<Lord_Nightmare>
the correct operator numbering is in the ym2608 datasheet from yamaha iirc
<ricky26>
Your warning is alas, too late.
<ricky26>
I did notice that. Like the registers were out of order compared to their descriptions. 😆
<ricky26>
I've just spent like half an hour trying to explain it back to a friend and I think I know enough to make the chip make noise now. Let's find out. :P
<Lord_Nightmare>
the operator register order (in the chip address space) in the ym2608, ym2610 and ym2612 is not in linear order: it goes 1 3 2 4 for each set.
<Lord_Nightmare>
yamaha calls them S1 S3 S2 S4
<Lord_Nightmare>
so TL for channel 1 operator 1 is at 0x40, for ch1 op3 it is at 0x44, for ch1 op2 it is at 0x48 for ch1 op4 it is at 0x4C
<Lord_Nightmare>
for channel 2, add 1 to all of those
<Lord_Nightmare>
for channel 3, add 2 to all of those
<Lord_Nightmare>
if you add 3 to all of those you get to some unused registers
<cr1901_modern>
I don't have good reg vals for YM2612, but initialize all registers to off. Algorithm 7. Then set channel 1 operator 1 to TL == 32, MUL=1, and "however you set the frequency to 440"... anything I'm missing?
<cr1901_modern>
Besides the bullshit way I explained "how to set the frequency" :P?