that fixed it! Now I just have to get past the geometry on the hd stage 🙁 image will boot in fake86/dosbox/virtualbox but on the xi8088 the MBR prints "missing operating system" so I think the geometry is off... argh.. might not be able to fix this until I get a floppy controller

I couldn't get that to work either. I set it up on my 8088 and then created a boot floppy image to use with dosbox.

I just realized the capacitorC54 I put on the board is a 9 - 50pf 250v trimmer cap instead of a 5 - 30pf 100v. I'm not sure how much the 250v matters compared to the 100v, "The Internet" leads me to believe that should be OK-ish?

However, my ISA bus speed may be pretty out of whack, maybe that's why some cards cause the beeping...

higher voltage spec wont matter. should should still be able to trim it to spec with a 9-50 vs 5-30.

I replaced the diode (D1), the capacitor (C43). I replaced the trace from speaker pin 4 to C31 and D1. I desoldered and tested all the resistors at the far end of the board. I desoldered a few of the 0.1uf capacitors but couldn't get any reading on them from my multimeter at all, I don't know what that means.

I've tested every logic IC on the board with my minipro and they've all passed 10 consecutive tests except a few that weren't in the test list (670, 92) but I ordered replacements for those.

Re: the transistor: My crappy multimeter reads "600" from center to each leg, and stays at "1" from each leg to center. I expect that's normal.

I've replaced the 12887 with a 12885, swapped the v20, 82c88, m82c37b, vt82c42n, SST rom, and almost all the logic chips in the pc/speaker circuit according to the diagram. I've basically ordered a full refresh of remaining logic chips from Mouser to arrive tomorrow.

Still the beeps. beeps beeps beeps beeps. I will look at replacing the 8254, 8259, and 8284 next.

pulled down and built XT IDE rom from github (fozztexx's branch). made a bunch of changes to makefile to get it to build on linux.

flash signature is 205 from 203 but its still 2.0.0 beta 3... I know fozztexx made some changes for serial..

I want to see if I can get the ide_xtl.bin (12kb rom) working since it has a bootloader inbuilt.. but 12kb might be too big. It should work since it pads the XTIDE bios with 24k of null to the XI8088 bios.. so I just need to make a 20kb of null and pad that.

just gotta burn and test right now.

it appears to work! F2 gives you boot menu.

Well I may have had a breakthrough of some sort, and maybe at least have a workaround.

I was swapping some ICs around and accidentally powered the system on with U26 removed (ALS175) and while the system post'd more or less normally, the speaker tones were played without the brief silence between notes, and the final tone continued to play, sounding quite a bit like my ongoing beeping problem.

So, I took some more recordings of the speaker tone and realized that it's actually repeating the final note from the system bootup, which is pic_freq/415 or A flat.

This was pretty intriguing, so I went into sound.inc and started tinkering with the values. I altered the tone values and the repeating note invariably ended up being the very last note played during BIOS post.

I've now set the only note to be played to "0", which has disabled all boot tones but I do hear a very low click as the speaker is enabled or disabled during boot.

I'm doing some more extensive testing but I'm pretty excited about this so far.

Now, I'm not a programmer by any stretch of the imagination unless Visual Basic 5 counts, but as I look through the code I notice that the notes definition is stored into the SI register. I wonder if some lingering data there is causing my problem farther on, should that register be cleared after the notes are pllayed?

I also notice the statements for turning off the speaker are different in the "beep" and "sound" code sections in sound.inc; in "beep" it's "xor al,03h ; turn off the speaker" and in "sound" it's "and al,0FCh ; turn off the speaker"

Well I'm just giddy at this point. It's been a half-hour of Champions of Krynn demo looping complete with pc-speaker uh... "music" and sound effects, and no gosh darned continuous beeping.

I do still occasionally hear a very soft click and/or sound effects/music skips momentarily but other than that it seems to be 100% A-OK so far.

So the turbo jumper; is that toggleable while the system is running, ala the old "turbo" switches on ancient xt/at cases? I'd assume so but I'm not willing to start yanking jumpers off while the system is live.

Anyone know if it supports a three-way toggle between off/on/software controlled?

so with updating the XTIDE rom, I read in the readme it now uses the standard LBA/CHS format that older and early 2 roms didn, so now my CF card works and boots into dos. WHOO!...

except now my keyboard isnt responding after a reboot (it takes 1 reboot to get the screen to come up)... then after a few reboots my screen doesnt initialise anymore.. now when I turn the machine on and reboot I get nothing (except the song so the cpu board is working)...

wtf.

Im going to reflash my rom but now its just getting frustrating 😒

hope the VGA card did not die 🙁 ugh.

The Turbo jumper is toggleable, I tested it last night, I just got a little nervous because of my speaker jumper incident...

I also pulled out my Kill-A-Watt power plug device and measured the xi8088 at 24 watts power consumption during boot, which is not bad at all. That includes the CompactFlash adapter and HXC floppy drive emulator.

BloodyCactus wrote:

so with updating the XTIDE rom, I read in the readme it now uses the standard LBA/CHS format that older and early 2 roms didn, s […]
Show full quote

so with updating the XTIDE rom, I read in the readme it now uses the standard LBA/CHS format that older and early 2 roms didn, so now my CF card works and boots into dos. WHOO!...

except now my keyboard isnt responding after a reboot (it takes 1 reboot to get the screen to come up)... then after a few reboots my screen doesnt initialise anymore.. now when I turn the machine on and reboot I get nothing (except the song so the cpu board is working)...

wtf.

Im going to reflash my rom but now its just getting frustrating 😒

hope the VGA card did not die 🙁 ugh.

So it turns on OK, but when you reboot the screen stays blank?

yeah, I think it has a timing issue with the vga. when you cold power turn it on, screen stays blank (cpu board works, plays the song etc), have to hit the reset button, and then it comes up nice and vga shows etc.

now, when I do reset, the screen changes, because the black level changes, you can tell its gone from monitor off to monitor on black screen...

keyboard lights flash when you cold power it on too, but on reset they dont. I need to look in bios and see if a warm reset causes a keyboard reset or not.

I'll pull cards and reseat things tonight, going to reflash my bios too, I've made a couple of changes to sergey's bios to see if I can fix the FF showing for century byte bug.

I haven't had any keyboard issues after reboots using ctrl-alt-delete, but I haven't wired anything to the reset jumper on the xi8088 so I haven't used that yet. All I see in the bios source is that it skips the memory check on warm reboot, nothing else?

I wonder if Sergey's 9000i "8088 friendly" bios would work. I expect that just removed any 80186/286 instructions for cards that aren't compatible...

A little tinkering, were all good. reseating of some plugs on my PS/2 KVM was the problem.

now I just need to get my CF image setup.

tested and got USE!UMB's working. have to edit or recomp the file. I think I will patch the code so you can pass command link params into it. ugh. author should have done that anyway...

Being a Tandy fan, I am going to repurpose an old Tandy 1000SL case for this system.

I do not plan on destroying or irrevocably altering it, I want it to remain (potentially) fully functional and capable of running the tandy motherboard if need be...

I do realize that I will be forced to sacrifice a few slots (1000sl only has five slot openings) but I plan on sticking my fdc, ems card, and xtide adapters in the far slots, since they have no absolute need for external slot access.

It will be super neat to find a way to repurpose the tandy front panel connectors for speaker out/reset/volume control but I very much doubt that will be possible without destroying the audio board. Maybe in time I can build a replica of some sort.

Oh, and with the turbo in software controlled mode, you can toggle speeds with ctrl-alt-minus and ctrl-alt-plus. I had hoped that was the case but I hadn't tried until tonight.

keenerb wrote:

I do realize that I will be forced to sacrifice a few slots (1000sl only has five slot openings) but I plan on sticking my fdc, ems card, and xtide adapters in the far slots, since they have no absolute need for external slot access

do you have sergey's XT-CF-LITE or an XTIDE from Lotek?

A lo tech c.f. adapter that uses a standard 40 pin connector. It relies on a separate compact flash interface card which I mount internally.

https://www.lo-tech.co.uk/wiki/Lo-tech_ISA_Co … ter_revision_2b specifically

I pulled apart this Tandy 1000SL late last night and took a look at the feasibility of repurposing the case for my xi8088.

It's a pretty big/roomy case, so it's no surprise that the motherboard actually fits well internally, none of the 8 slots will be blocked completed, and only a few are blocks length-wise by the built-in speaker. Right now the only thing holding it in place are the two expansion cards.

The mounting holes for the Tandy motherboard are (unsurprisingly) completely wrong for the micro-atx backplane. The three along the back of the case are not in any danger of causing a short circuit but the three staggered along the middle of the case are of great concern to me.

The two smallish cards above and to the left of the motherboard are the audio interface card and the joystick/keyboard interface card. I've left them in there mostly to avoid losing them in my giant stack of parts. However, when I looked more closely at the audio interface card, it occured to me that possibly I could use that as an interface to a Soundblaster card.

The audio interface card has mic/line in, audio out, volume control, and a reset button. There are eight pins connecting the daughterboard to the main 1000SL motherboard, so that has me wondering if there's simply four sets of two pins, one set per front-panel connectors. If that's the case, I should be able to leverage that potentially utilize the internal Tandy speaker along with the built-in amplifier chip and volume potentiometer for audio, and the input, speaker jack, and reset button. At the very LEAST I think I can use the front speaker (sans volume control) and reset switch.

*edit*

I'm going to make this into a seperate post, this is far beyond any xi8088 specific discussion.