VOGONS


First post, by scruit

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EDIT: THe issue was solved by installing a new CPU board. I just had to wait until one popped up on ebay at a reasonable price because some folks are asking $250 for them. I got one for $45 and the server just started right up.
I will continue to troubleshoot the original CPU board as it has dual P166s instead of the single P100 that the replacement board has, but now I know which board is bad and have a functional unit to compare with.

Notes: I went through a few memory sticks after being told the system would be very picky on memory. I got edo, ecc, different sizes, different speeds. Old cpu board was dead on all of them - new board works fine with all of them. Don't let a dead board send you down the memory rabbit hole. Any compaq-branded 72pin memory seems to keep it perfectly happy.

ORIGINAL POST:

Backstory:

Found my old Proliant 1500 tower in the attic where it has languished for 20 years. Trying to get it working. All I have connected is the power supply, backplane, daughterboard (one cpu). I have original compaq memory, but the behavior I see does not change with the memory being in place or not in place, so the memory is out of the board right now.

Symptoms:

- PSU fan power up. Green LED on backplane lights up. No video despite SW1.1 being set to enable onboard video (isa video card plus sw1.1 set to disable onboard video gives no video either)

- No beeps.

- POST card shows all dashes.

Basic checks:

- None of the power rails are shorted either on backplane or daughterboard.

- All 3.3v, 5v, -5v, 12v, -12v connections show hundreds of KOhm desistance to ground.

- All of the stated power outputs from the PSU match what is spec'd for the pin (the "5" is 4.95v and the N5 is -4.95v)

- 14Mhz OSC signal good on EISA

- 33Mhz CLK signal good on PCI and daughterboard, and at the CPU, when the daughterboard is installed

Current Approach:

I am focusing on the EISA slots as I can get oscilloscope readings from the pins easily. I am checking the address and data lines. This is where I am having issues.

Testing setup:

- Backplane on my bench with daughterboard plugged in. PSU connected. Oscilloscope at the ready.

Basic observations:

- Powers, grounds and OSC on EISA slots are good.

- Data and address pins are all connected across the EISA slots.

- The data lines D0-D7 at the EISA slot go to pins SD0-SD7 respectively on the 82374 EISA controller

- Half of the data lines (D7, D6, D5, D3) show something akin to a "square wave" but the lows have a rising value almost like a capacitor charging.

- The other data lines (D4, D2, D1, D0) show a rounded sawtooth pattern.

- The first two address lines Addr0 and Addr1 (connected directly to the 82374 EISA Controller SA0 and SA1 respectively) show a good square wave.

- The remaining address lines from Addr2 to Addr16 (Connected to a pair of Ti F543 octal bus transceivers) show good square wave inputs (0v-5v measured on the output of the 82374 EISA controller and confirmed at U9/U17 "A" side of bus transceivers) but VERY shallow high outputs (matching inputs for low-high with amplitude from 4.0v-4.2v measured on the B side of the bus transceivers and confiremd at ISA slot.)

- The bus transceivers have V+, Gnd that both check out. They also have Latch/Copy/Output enable pins for both both directions. Copy and Output as held low for AB and Latch for AB (sending data from eisa controller to isa slots) pulses low as expected. The Copy/Output/Latch for BA (which would be "sending and address from isa slot to eisa controller), if that is even a thing) are held low all the time.

- The computer spends some amount of time, between5 and 30 seconds, giving these signals and they it kinda "gives up" and all the data and address lines go high. The OSC still hums along at 14mhz.

- If I power off the PSU and try again then this behavior repeats (good signals from EISA controller to the bus transceivers, bad signals from the transceivers to the slots) withthe computer "trying" to boot for some amount of time then gives up and all signals go high.

- The amount of time that the psu is OFF between tests directly impacts the amount of time the computers "tries" to boot. If it is off for more than a couple of minutes then I get 25-ish seconds before it gives up. If I power it down for a shorter time then the shorter that "trying" time period gets. If I power it off and back on within a couple of seconds then I get 6-10 seconds max.

- Memory in or out does not change any observed behavior

Theory:

- I think there is some capacitance or heat issue that is causing the system to give up.

- I'm confused by the output of the F543 octal bus transceiver that handles Addr02-Addr16. If it was one IC acting liek this (good input, bad output) then I would assume it is bad, but what are the chances that BOTH transceivers would go bad? Both transceivers' AB latch enable pins are routed to the EISA controller (ABFULL and SALE pins)

- Having two different types of bad waves on the data pins suggests the issue is fundamental and not a result of a step in POST failing. I think it's failing to POST because the address and data lines are not functioning correctly.

- I checked the PCI slot stuff, which is handled by an 82375 PCI-EISA Bridge and found the waveforms look better. I suspect whatever is killing the address/data lines on the EISA slots is causing the system to stop trying to boot. I'm checking for anything that may be shorting out the data/address lines on the ISA bus but it's very difficult because all I have is my eyes and a multi-layer pcb. I cannot find a schematic for this board.

Waveforms:

- Here are the oscilloscope outputs: https://imgur.com/gallery/643LVkh (In this one just look at the data lines - the address line waveforms below are better)
- Here are oscilliscope waveforms for communication into/out of the octal bus transceivers: for EISA address lines 02-16 :
https://imgur.com/gallery/HD5Yp3n

Datasheets:

F543 Octal Bus Transceiver: https://www.ti.com/lit/ds/symlink/sn74f543.pdf

EISA Slot: https://en.wikipedia.org/wiki/Extended_Indust … SA_Bus_pins.png

82374 EISA Controller: https://pdf1.alldatasheet.com/datasheet-pdf/v … EL/82374EB.html

Last edited by scruit on 2023-01-01, 17:25. Edited 1 time in total.

Reply 1 of 15, by weedeewee

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if possible try to add a timebase to the waveforms.
How's the ripple on the power rails ? at the connector of the psu & at the other end of the board, incl voltage levels at that end.
Considering this is quite an old machine... Has it had any electrolytic capacitors replaced yet ?

Right to repair is fundamental. You own it, you're allowed to fix it.
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Reply 2 of 15, by rasz_pl

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I have zero experience with EISA, personally I would start by

-checking cpu/bios voltages
-monitoring BIOS data/address pins during boot

https://github.com/raszpl/FIC-486-GAC-2-Cache-Module for AT&T Globalyst
https://github.com/raszpl/386RC-16 memory board
https://github.com/raszpl/440BX Reference Design adapted to Kicad
https://github.com/raszpl/Zenith_ZBIOS MFM-300 Monitor

Reply 3 of 15, by pentiumspeed

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Hi! I have Proliant 1500 too not in original chassis, but I figured out how to make it work without special stuff.

Make sure you have installed correctly and set the dip switches to defaults first before starting the configuration once you get that going. Once you run the configuration and set it up, it will show you the recommended dip switches settings.

Make sure you have good battery, I used 3 cell (3x 1.5V) external battery for CMOS settings. You need to get ESR meter to check the capacitors inside the power supply. Discharge the power supply's main capacitors first with a 100 or 220 ohm resistor.

Cheers,

Great Northern aka Canada.

Reply 4 of 15, by scruit

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pentiumspeed wrote on 2022-04-03, 17:03:
Hi! I have Proliant 1500 too not in original chassis, but I figured out how to make it work without special stuff. […]
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Hi! I have Proliant 1500 too not in original chassis, but I figured out how to make it work without special stuff.

Make sure you have installed correctly and set the dip switches to defaults first before starting the configuration once you get that going. Once you run the configuration and set it up, it will show you the recommended dip switches settings.

Make sure you have good battery, I used 3 cell (3x 1.5V) external battery for CMOS settings. You need to get ESR meter to check the capacitors inside the power supply. Discharge the power supply's main capacitors first with a 100 or 220 ohm resistor.

Cheers,

Thanks for the reply.

I have SW1 (on the backplane, near the motherboard power connectors) tested at the settings it already had while in the attic (off, on, off, off,on, off) and at the "default" settings (all off) from https://www.ultimateretro.net/motherboard/man … 15117414720.pdf howver I actually found an old post of YOURS that said those are mislabeled...? Proliant 1500 or 1500R motherboard and front panel wiring information wanted.

Also, this is very curious... I just went to double-check the sw1 switches on the processor daughterboard. They are on/on/off/on which was how it was set when it was running before, and I read that means 166mhz which should match the single P166 I have in there (but cannot find the doc that told me this setting, so looking again).

BUT

I decided to verify that the processor speed switches work by moving them back and forth then testing continuity. Switches sw1.2 (and .3 and .4) all show short / open correctly depending on position, but sw1.1 is open all the time. I need to find my reference for those switches to determine the effect of sw1.1 being open (effectively giving me off/on/off/on instead of on/on/off/on) and see if that would explain it acting weird. Maybe I can jump that with a wire to see if it gives me the correct speed. I suspect that the clock speed setting being off is going to result in unpredictable behavior relating to sync/latch/clock cycles not lining up correctly.

Going to test that and report back.

EDIT: Jumping that switch has no effect. The CLK pin (b16 on PCI and at the clk pin of the cpu)
Looking more closely, those settings for cpu speed,testing all settings and monitoring frequency and voltage:

After running through some karnaugh maps:

sw1.1 and sw1.2 have no apparent effect on frequency and amplitude. Maybe these are a multiplier?

If sw1.3 on and sw1.4 on then frequency is 33mhz, stable, and amplitude is 1.5-3v
If sw1.3 off and sw1.4 on then frequency is 33mhz, stable, and amplitude is 1.5-1.8v
If sw1.3 on and sw1.4 off then frequency is 50mhz, unstable, and amplitude is 1.6-2.1v
If sw1.3 off and sw1.4 off then frequency is 40mhz/unstable, and amplitude is 1.5-1.8v

Last edited by scruit on 2022-04-04, 19:50. Edited 1 time in total.

Reply 5 of 15, by pentiumspeed

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Do that.

The switches on CPU board is first 2 for fsb or multiplier, other last 2 is for either. Forgot which was.

Compaq bios will say use 60ns memory modules if using fsb 66 MHz before proceeding. Always FPM parity modules.

Cheers,

Great Northern aka Canada.

Reply 6 of 15, by scruit

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pentiumspeed wrote on 2022-04-04, 19:29:
Do that. […]
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Do that.

The switches on CPU board is first 2 for fsb or multiplier, other last 2 is for either. Forgot which was.

Compaq bios will say use 60ns memory modules if using fsb 66 MHz before proceeding. Always FPM parity modules.

Cheers,

(I edited my erlier post but took so long you already replied. Add the edits here ...)

Jumping sw1.1 had no discernible effect. I measured the CLK pin (b16 on PCI and at the clk pin of the cpu)
Looking more closely, those settings for cpu speed,testing all settings and monitoring frequency and voltage:

After running through some karnaugh maps:

sw1.1 and sw1.2 have no apparent effect on frequency and amplitude. Maybe these are a multiplier?

If sw1.3 on and sw1.4 on then frequency is 33mhz, stable, and amplitude is 1.5-3v
If sw1.3 off and sw1.4 on then frequency is 33mhz, stable, and amplitude is 1.5-1.8v
If sw1.3 on and sw1.4 off then frequency is 50mhz, unstable, and amplitude is 1.6-2.1v
If sw1.3 off and sw1.4 off then frequency is 40mhz/unstable, and amplitude is 1.5-1.8v

FPM vs EDO for Proliant 1500.... I've heard people arguing "Only FPM" and "only EDO ECC" and "Only EDO non-ecc". I have pairs of 60ns 72pin simms fpm and edo non-ecc, bottom two simm sockets (SIMM1 and SIMM2) but no change in behavior.

Reply 7 of 15, by pentiumspeed

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Probably multiplier locked processor but two of these switches is fsb.

No, not either EDO or ECC the service manual is explicit. Proliant 1500 is low end machine using FPM parity modules, in pairs at a time only and, two 4MB modules minimum, up to 32MB modules. Either 70ns for fsb 60MHz or 60ns for 66MHz fsb.

Cheers,

Great Northern aka Canada.

Reply 8 of 15, by pentiumspeed

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From my notes:

Update:

Dual processor board for Proliant 1500,
Investigated the dipswitch and BF0 and BF1 with multimeter. Indeed, sw 1 for BF0 and sw 2 for BF1, which can run either 100, 133, 166 and 200 using multiplier unlocked Pentium 200 processor.

Setting SW 1 or SW 2 or both "on" pulls low.

My comment: the SW3 and SW4 is can be 50MHz, 60 and 66MHz.

Cheers,

Great Northern aka Canada.

Reply 10 of 15, by scruit

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weedeewee wrote on 2022-04-03, 13:10:

if possible try to add a timebase to the waveforms.
How's the ripple on the power rails ? at the connector of the psu & at the other end of the board, incl voltage levels at that end.
Considering this is quite an old machine... Has it had any electrolytic capacitors replaced yet ?

Thank you for your reply. I appreciate you taking the time.

More waveforms:
https://imgur.com/gallery/L6nWINT
The ripple looks pretty minor to my untrained eye. Within 1-2% and rippling with 50hz.
Timebase is at the bottom if these new ones. I captured an "address line input" versus "latch enable" relationship with timebase.

There are no electrolytic caps on the backplane or cpu daughterboard. Likely a bunch in the PSU but I don't see anything that tells me the PSU is a problem so wasn't planning to pull it apart.

Reply 11 of 15, by scruit

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pentiumspeed wrote on 2022-04-04, 20:43:
From my notes: […]
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From my notes:

Update:

Dual processor board for Proliant 1500,
Investigated the dipswitch and BF0 and BF1 with multimeter. Indeed, sw 1 for BF0 and sw 2 for BF1, which can run either 100, 133, 166 and 200 using multiplier unlocked Pentium 200 processor.

Setting SW 1 or SW 2 or both "on" pulls low.

My comment: the SW3 and SW4 is can be 50MHz, 60 and 66MHz.

Cheers,

I am curious. The effect of not having memory installed should be to post partially, then give an POST code / beep error or similar regarding failed memory check - correct? The behavior I get (specifically the address lines being pulled high after the bus transceiver for the ISA ports) does not change regardless of what memory I put in there, or if I leave the slots empty.

I'm also trying to figure out how to measure the actual FSB at the cpu. That level of docs are not really available any more.

Reply 12 of 15, by pentiumspeed

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Make sure the processor board is correct for particular models is true. Not all processor cards is compatible even can be plugged in.
I have known working processor boards one is dual processor, used single CPU in default with 512K cache, 222925-001 and single CPU board with 16MB onboard 169174-002, these two works in this proliant 1500. None supports MMX processor due to VRM but these two does support up to Pentium 200MHz. I used their default CPU if installed on the board first to get working first.

And my notes is correct about switch configuration is incorrect according to the service manual, use the configuration diagram displayed during setup when running configuration disks. But disabling the onboard video via dipswitch is correct on the service manual. Onboard video disabled, I can use either ISA or PCI video card, cirrus logic or S3 is more compatible PCI cards and faster.

And I do confirm that I can disable the onboard SCSI via configuration software when dipswitch is correctly set as previously explained.

Floppy drive is standard as I used a generic floppy drive. I can also can use dual SATA PCI-X plugged into PCI slot or dual ATA PCI adapter card both are by 3ware.

Booting up take awhile. Set it up by defaults first and you need 4.5V battery plugged in, two battery connector is wired in parallel, use either.

Cheers,

Great Northern aka Canada.

Reply 13 of 15, by scruit

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rasz_pl wrote on 2022-04-03, 13:53:

I have zero experience with EISA, personally I would start by

-checking cpu/bios voltages
-monitoring BIOS data/address pins during boot

This is interesting...

There are 3 GAL22v10C chips on the backplane. Eproms, essentially. One is next to the bus transceivers, and has a good clock signal on pin 26.

The other two are labelled "SYS MGT ROM" and "BIOS" in the silkscreen. NEITHER of these has a clock signal on Pin 26. The signal appears to be pulled high just like the address lines between the octal bus transceivers and the isa slots.

Also noted that the SCSI IC (NCR 53C825) has a good clock signal, but the video controller (Cirrus Logic GD5420) does not. I'm going to map out which ICs are expecting a clock and which are getting it. I am wondering why the clock signal is not making it there. Also, which clock pins are just connected together and which are not.

Reply 14 of 15, by scruit

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pentiumspeed wrote on 2022-04-04, 21:42:
Make sure the processor board is correct for particular models is true. Not all processor cards is compatible even can be plug […]
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Make sure the processor board is correct for particular models is true. Not all processor cards is compatible even can be plugged in.
I have known working processor boards one is dual processor, used single CPU in default with 512K cache, 222925-001 and single CPU board with 16MB onboard 169174-002, these two works in this proliant 1500. None supports MMX processor due to VRM but these two does support up to Pentium 200MHz. I used their default CPU if installed on the board first to get working first.

And my notes is correct about switch configuration is incorrect according to the service manual, use the configuration diagram displayed during setup when running configuration disks. But disabling the onboard video via dipswitch is correct on the service manual. Onboard video disabled, I can use either ISA or PCI video card, cirrus logic or S3 is more compatible PCI cards and faster.

And I do confirm that I can disable the onboard SCSI via configuration software when dipswitch is correctly set as previously explained.

Floppy drive is standard as I used a generic floppy drive. I can also can use dual SATA PCI-X plugged into PCI slot or dual ATA PCI adapter card both are by 3ware.

Booting up take awhile. Set it up by defaults first and you need 4.5V battery plugged in, two battery connector is wired in parallel, use either.

Cheers,

Thanks for your reply.

I have tried a trident isa card for video and swapping sw1.1 on the backplane to disable onboard video, but nothing. That does not actually surprise me given the ISA address and data lines are all messed up.

I'll obtain a 4.5v battery.

Reply 15 of 15, by scruit

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pentiumspeed wrote on 2022-04-04, 20:43:
From my notes: […]
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From my notes:

Update:

Dual processor board for Proliant 1500,
Investigated the dipswitch and BF0 and BF1 with multimeter. Indeed, sw 1 for BF0 and sw 2 for BF1, which can run either 100, 133, 166 and 200 using multiplier unlocked Pentium 200 processor.

Setting SW 1 or SW 2 or both "on" pulls low.

My comment: the SW3 and SW4 is can be 50MHz, 60 and 66MHz.

Cheers,

Circling back to this... Thank you for your response.

My observations did not match yours. You clearly have succeeded so I'll assume my observations are incorrect, or I'm observing incorrect behavior.

So not only did I find that sw1.1 is permanently open (mentioned above I think), but also sw1.3. I traced BF0 and BF1 from the empty socket and found that only one of them was influenced by the switch. After figuring this out I soldered a bodge over sw1.1 and I get correct bus speed now. Still no post but closer.

For reference, and for anyone else looking in the future:
BF0, cpu pin Y33, goes to sw1.1 on the "processor" side of the switch. It emerges from the "memory" side of sw1.1 then goes to the back of the board (same area) and hits R33 ("51o" = 51 ohm) at the bottom. The top of that resistor is grounded.
BF1, cpu pin X34, goes to sw1.2 on the processor side. Emerges from the memory side of sw1.2 then stays on the from of the board and hits R50 ("510" = 51 ohm) on the memory side. The other end of that resistor is grounded.

sw1.3 is also permanently open, however the correct setting for this is off anyway, so that is a note I will make but no action needed.

I did note also that these settings don't affect anything on the st49c155 (clock multiplier) U43 on the backplane (next to the bios rom) so I suspect the frequency select pins A0/1/2 are locked on the correct settings intentionally and only handles backplane stuff (disks, keyboard, onboard video etc)

Instead, sw1.3 and sw1.4 (processor side) connect to pins 23 and 24 (respectively) of the ICS9158-04 (frequency generator and integrated buffer) U10. Same purpose as U43 - generates multiple frequencies from a base 14mhz input (Y1) and 3 frequency select pins (sw1.3 is pin 23, "FS1" and sw1.4 is pin 24 "FS0"). The datasheet for it shows that the output is 66.6Mhz on CLK2 out when output enable is on. FS2 high/low has no effect.

SW1.3 OFF (open) results is FS1 seeing a 1 (pullup resistor?). (Otherwise, the memory side of SW1.3 goes to ground via R36 on the back of the board.)
SW1.4 ON (short) results in FS0 seeing a 0. (Otherwise, the other side of sw1.4 goes to 5v via R149 on the back of the board)

The datasheet for it shows that FS0=0 and FS1=1 results in an output of 66.6Mhz on CLK2 out. FS2 1/0 has no effect.

This chip sends a unique clock signal to many other devices not handled by U43, like the scsi controller (via A89 on the daughterboard connector)

Still trying to connect the dots for why the bios does not see a clock signal.

Last edited by scruit on 2022-04-09, 23:01. Edited 1 time in total.