'Read TLB miss exception' - RAM issue? - Printable Version

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'Read TLB miss exception' - RAM issue? - DVE - 06-11-2022

Hi all,

I'm trying to install IRIX 6.5 on Indigo 2. 
I am able to run FX and make the repartition of the drive, but when I select the "Install software", I get this error:

   

I have 2 sets of RAM, 4 modules 64 MB in total on each set, one was preinstalled in the machine when I bought it, and a second one I got on eBay separately. Replacing one with another did not help. How big is the chance that both RAMs are not working with my Indigo2? 

This link https://wiki.preterhuman.net/Read_TLB_miss_exception,_bad_address tells that it can be a RAM issue, but then I'm curious how it was working before (if it was, maybe the seller replaced the RAM with some random module? or maybe the module silently died within years?).

The "hinv" command shows 64 MB, "diagnostics" did not get any errors. 

Any ideas?

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RE: 'Read TLB miss exception' - RAM issue? - weblacky - 06-11-2022

Please state the exact version of Irix you’re trying to install.

Please provide a picture of how the RAM is currently installed in the machine.

Please provide info on the RAM you bought (eBay page or product page).

Please show your hinv and say the model of Indigo2 as there are like four major variations of the Indigo2 system.

Your description of the RAM sets is a little ambiguous. If you’re saying that you have eight modules total where originally you had four SIMM modules, that totaled 64MiB, and you attempted to ADD 64MiB more to the system, through an eBay purchase, so you expected to see 128MiB afterwards.

Then my only immediate suggestions would be to ensure you checked the manual to know the order of module sets (BANK numbering and installation order of modules), also ECC or EDO SIMMMS don’t work on the Indigo2. Has to be older 72-pin SIMM fpm WITH PARITY (x 36) memory only.

I think Indigo2 will ignore SIMMs it doesn’t like versus just refusing to boot if they are close in standard but have like no parity or the like.

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RE: 'Read TLB miss exception' - RAM issue? - DVE - 06-11-2022

Thanks for the answer.

The RAM I bought, is listed as "16MB ps/2 PARITY EDO Simms Server Memory 4mx36 5v 72p 60ns Samsung" - https://www.ebay.com/itm/284663991460
I bought 4 chips, so I have 4x16 = 64 MB.

I replaced the 64 MB original RAM with these chips, but the problem still exist. All 4 are installed in BANK A on the motherboard.

The "henv" shows this:

System: IP28
Processor: 195 Mhz R10000, with FPU
Primary I-cache size: 32 Kbytes
Primary D-cache size: 32 Kbytes
Secondary cache size: 1024 Kbytes
Memory size: 64 Mbytes
Graphics: Solid Impact
SCSI Disk: scsi(0)disk(1)
SCSI CDROM: scsi(0)cdrom(5)

"EDO SIMMs don’t work on the Indigo2" - maybe it's an answer, thanks. But it is still weird that I get the same error with an original RAM as well.

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RE: 'Read TLB miss exception' - RAM issue? - weblacky - 06-11-2022

What version of Irix are you installing?

The Indigo2 is supported up to (and including) version 6.5.22, if you’re trying to install a version higher than that, it won’t work. 

That’s why I asked what version. 


Also PS/2 ram is special!  It’s even wired differently than normal RAM.  Those are non-standard SIMMs, if they really are PS/2 compatible.  But looking at the eBay auction I think your seller is just full of BS, and just put the term there. But yeah EDO memory is more common on the market today but it’s a much later form of SIMM memory. Please just buy normal FPM PARITY SIMMs. 

A hint is that FPM memory is the standard before EDO so you’ll never find the two terms together

You’re lucky that this is one of only two machine models that support normal PC memory. Everything else is proprietary and therefore much harder to get your hands on. Look for 16MiB or 32MiB modules, they aren’t that pricey.  Usually from a memory supplier so you have a warranty and they have been tested.

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RE: 'Read TLB miss exception' - RAM issue? - DVE - 06-12-2022

Thanks a lot for the answer, I'll get another modules (it's a black hole in the budget, he-he )

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