It should be noted that the BIOS dumping feature of the program cannot dump the real BIOS on stuff past 486 era when BIOSes began to be larger than 64KB, use compression and started to extensvely use shadowing feature of every chipset so what is in the normal BIOS area isn't even what is on the physical BIOS chip but decompressed and run-time modified on top. Video BIOSes are having a similar problem.
You need to actually dump the physical chips to get all the data out. If your chipset is supported, Uniflash can work though.

Tiido wrote on 2023-02-25, 13:18:

It should be noted that the BIOS dumping feature of the program cannot dump the real BIOS on stuff past 486 era when BIOSes began to be larger than 64KB, use compression and started to extensvely use shadowing feature of every chipset so what is in the normal BIOS area isn't even what is on the physical BIOS chip but decompressed and run-time modified on top. Video BIOSes are having a similar problem.
You need to actually dump the physical chips to get all the data out. If your chipset is supported, Uniflash can work though.

Thanks, very useful to know

Replacement eproms

T48 programmer
Got something like this with a bunch of attachments that fit the 27c010

Now to google how to rip the eprom and hack video bios to CRT mode 😀

BIOS Extract using a T48 Programmer

Handy piece of kit - i was able to extract the real BIOS to start examining its contents.

BIOS EXTRACT

I've included both formats in case anyone else needs.
AT27C010@PLCC32 - BIN (128KB)
AT27C010@PLCC32 - HEX (361KB)

BIOS Hacking to Change Video Boot Mode

While i managed to get most of the way through it, my EPROM chips ordered from Aliexpress had already been written too - this isn't too great for chips that can only be written once - so i now need to wait for more parts 🙁
I believe I have found where the address in the bios file that defines if it will boot in simultaneous mode or crt only mode or flat panel only mode but i need verify if it will result in some validation error on boot (ie checksum check etc)

Understanding the VGA Bios
I was fortunate enough to find an OEM Video Bios editor (BMP548P) for this specific chip (it looks to be for a PCI card version of the video chip based on some settings but handy eitherway). This provided some excellent material to understand what was going on between setting options and what appears int he video bios file.

In examining the AT27C010 ic contents via a hex editor, i could also see the display text that the video card outputs near the start of the file, so initial signs were good - i could see where in the BIOS file - the vga bios information started and finished (using the previous vga bios extract), again good signs.

It is worth noting that absolutely none of the Phoenix editing tools i had found would work with the .bin extract! Nor did the OEM Video Bios editor (BMP548P) wanted to use vga bios bin i was able to extract from an earlier post.
What i was able to do however was use BMP548P to help me discover where the display mode was being stored in the bios file.

When I started BMP548P inside a windows xp virtual machine, this is what it looks like. You see it immediately shows the boot message the user can edit:

Pressing the 'tab' key a few times - took me to what i was looking for in the 'Display Determination' page.
As you can see its highlighted the defaults of:
- 'Analog Display Boot Type' option = Simultaneous boot
- 'Adjust Shift in 40 Col. & Pack Pixel Modes?' option = yes (which is the setting that is making weird refresh rates while the system is in simultaneous display mode)

A few further screenshots to highlight what options are shown.

While i couldn't import my video bios settings into this application, it was able to save/ export was in BMP548P via pressing <F10>. This created a user specified .dat file - which on further evaluation under a hex editor was very similar to the vga bios extracted from the 486. Again good signs, as both appeared to be in a .bin format

The next step was to see if i can use the export to narrow down the address of where BMP548P is saving the display determination.

I did this by exporting 3 x versions of the BMP548P .dat file - keep all values the same EXCEPT the display mode.
- simultaneous mode
- CRT mode
- Flat panel mode

Then used a bin comparison tool (in this case VBinDiff-3.0_beta5) - this compares every value between two files and highlights any differences:

This helped to identify 3 values that had changed between settings.

To narrow this down further, I exported the exact same settings (ie simultaneous mode) as 2 x different files - which should of resulted in two files being identical. Those 2 values as shown the picture above were also different despite all configuration settings being identical - the only thing i could think of was the difference in time between saving each file. Therefore i am assuming that these 2 values may either represent a date / time or some form of checksum using the system date and time.

Either way the 3rd value looked to be the location of the display determination.

Display Determination - settings

Narrowing it further, the setting looks to be saved at the Hex address:
Position = 0199

Comparing Hex values:
40 = Simultaneous Boot
c0 = CRT Boot
00 = FP Boot

The location is also the same in the T48 extract (with the values also appearing to align), so the next step is to order more ic's and test the theory.

Getting closer....

Thanks for sharing this, I had a similar problem with my Advantech PCA-6145 board which seemed to be set up with some odd settings for the last LCD it was connected to. I was getting the same thing you had, although I think I had all sorts of video trouble with the Chips control panel crashing the PC at some point.
I have two of them and compared the BIOS between them only finding a couple of bits difference so it was fixed easily enough, but it's likely this will work for most Chips & Technologies CT65548 equipped SBCs and maybe laptops.
Similar thing to here - you can use a crt.com file or debug commands to do the same, but having it in BIOS is nicer: Re: C&T 65550 CRT BIOS

It seems a bit odd that they went with an OTP EPROM chip for this system since the video BIOS does usually need modification for the SBC's application. Maybe that's not the original? Seems possible since there's no BIOS vendor sticker on there. I also have a PCM-4825 which uses a PLCC32 like your board and that's an SST 29EE010 on there - if the pinout matches maybe you could use an EEPROM instead now that you've got the T48 programmer.
Good luck with your ROM modifications with this board 😀 I really like the enclosure and setup you've got for it now.

Thanks! I've seen many of your posts which have given me hope and some great ideas / useful avenues to explore.

I have many questions as to what the intended purpose of this SBC was. I suspect using a one time write eprom may have been to increase its durability or possibly for the vendor to retain control of servicing (who really knows).

I was wondering if these eproms are interchangable with the flashable ones (i have a few datasheets that I was going to compare at somepoint) but at this stage fixing the video mode at the source is the main goal.

Thermalwrong wrote on 2023-03-18, 19:53:

Similar thing to here - you can use a crt.com file or debug commands to do the same, but having it in BIOS is nicer: Re: C&T 65550 CRT BIOS

That was a really useful thread I found a few weeks ago (note: the links you posted in that thread helped me to source the OEM tools referenced above and helped me further deep dive into the root cause of all this - so thanks too for sharing and documenting your knowledge).

While the debug commands in that thread didnt work for me on this chipset (not sure why), my frantic googling helped me to find an awesome zip of CT video drivers and importantly a number of .com files which i then uploaded and posted on that thread (to make it easier to find via google rather than it being buried in this thread).

Ie. It included CT.com, SM.com, off.com, on.com - these are must have files for anyone wrestling with similar video issues 😀

They do a great job of fixing the screen issues via dos and I use those in my autoexec.bat to keep my lcd vga happy.... but it irked me that these only take effect after for dos has booted (so boot and bios menus are still a little off) or well after window 95 has finished loading.

As for pc case, at one point I was hoping to build a retro era specific mini pc case, but perspex kinda shows all the patch work discovery in all it tinkering glory. Do you have links to pics of some of your SBC collection? Would be great to have a look.

And while I can now burn eproms...

Overall Outcome = Fail (for now) - see later post for update on how this was done.

With my new eproms I tried:
-Edited the single value and change (as per previous post) and burn eeprom
= video fail
No video, 2 beeps pc speaker, disk activty
(Repeated this test twice with another that overwrote some display text )

Copied the entire example crt video .dat into bios and burnt eprom
=video fail
(No video, no beeps but disk activity.
UPDATED 27/3 - the example crt.dat has an 8bit checksum =00. This would explain the lack of beeps ie it was considered valid even tho it did not show video output)

Burnt original eprom image to new eprom
=video works
Systems works as previous with same video issue (this was to rule out effect of new ic chips)

The positive is the bios backup works using the newer ic!

UPDATE 25/3
Issue - Missed Checksum step!
I completely missed the step of needing to check / change overall checksum value in the bios.

Further Info (UPDATED with additional links): http://www.xtremesystems.org/forums/showthrea … a-bios-checksum

Also useful background on how 8bit checksums are calculated:
https://minuszerodegrees.net/misc/8-bit%20checksum.htm

Also excellent reference on Bios and how they are structured for pc and tips on editing:
https://thestarman.pcministry.com/asm/bios/index.html

BIOS Checksum - Validation
Using the trial version of Hex Workshop v6.7 (referenced in the article linked above and it works on win10) , I generated a checksum for the original bios file and each bios file I edited / tampered with. Original rom the "8 bit checksum" = 0 00 VS the modified rom "Checksum (8 bit)" = 26 1A

I believe this is the result i need to match to pass the bios checksum validation. Also to note there are other freely available hex tools that will also calculate the checksums (if you are using hex workshop, make sure you right click and clear the previous checksum results when comparing files or scroll further down to find the second file calculations)

My understanding is checksum validations were implemented to quickly identify corruption in the bios data through either degradation of the rom itself over time (another interesting topic worth googling, as these things don't last quite as long as most people would expect) and/or to identify unauthorized tampering (i.e. virus/hacking). They used a few different algorithms used to calculate them (https://en.wikipedia.org/wiki/Checksum), with the calculated checksum value inserted somewhere back into the bios at some location (ie algorithm performed on a range of data and then included in a part of the file/eprom) - there appears to be quite a few variations in how this was implemented.

So from a old PC BIOS modification point of view, once edits / hacks have been made to a BIOS (in this case, editing the video modes inside the video bios) we will get new checksum result and it will not match the checksum value embedded 'somewhere' in the bios and as a result fail somewhere in the boot cycle.

For reference here is what the checksums look like
Original BIOS - Checksums

1Document	Algorithm	Checksum	Checksum/Digest
2AT27C010@PLCC32.BIN	"Checksum (8 bit)"	0	00
3AT27C010@PLCC32.BIN	"Checksum (16 bit)"	53760	D200
4AT27C010@PLCC32.BIN	"Checksum (32 bit)"	10277376	009CD200
5AT27C010@PLCC32.BIN	"Checksum (64 bit)"	10277376	009CD200
6AT27C010@PLCC32.BIN	"CRC (16 bit)"	17588	44B4
7AT27C010@PLCC32.BIN	"CRC/CCITT (16 bit)"	58108	E2FC
8AT27C010@PLCC32.BIN	"CRC (32 bit)"	1563578425	5D325039
9AT27C010@PLCC32.BIN	"Custom CRC-16"	17588	44B4
10AT27C010@PLCC32.BIN	"Custom CRC-32"	1563578425	5D325039
11AT27C010@PLCC32.BIN	"MD2 (128 bit)"		A962EB715944E4E5D4D3177337374872
12AT27C010@PLCC32.BIN	"MD4 (128 bit)"		67CAA003097E5DA1062A8A6B04F55498
13AT27C010@PLCC32.BIN	"MD5 (128 bit)"		7FBD7EE0D1BAFD0B4B9C1F2C482ACBD8
14AT27C010@PLCC32.BIN	"SHA-1 (160 bit)"		4F5DB1CCC12B1B7E01FDF2A1E26D141A45874BC7
15AT27C010@PLCC32.BIN	"SHA-2 (224 bit)"		76BDE6BB1B023FF7DADCF8A61C2E5867411AB9CB27508B6D7E725207
16AT27C010@PLCC32.BIN	"SHA-2 (256 bit)"		0229DF3B102C75CB67E185FA639A119065B978D5B4656CDF770331762DDC2629
17AT27C010@PLCC32.BIN	"SHA-2 (384 bit)"		E8A5617211E4EAAA4E1645D318BC452EE10D2B514CB45C921297803CD1497BC64D0BAE4E765C4C8A3F5B163BC6D9F649
18AT27C010@PLCC32.BIN	"SHA-2 (512 bit)"		5D16AEE88850E3B1C6262CA6316680B3279BC076CA77183437F326F5E264839213D0D8F3E72AB2F6E411230DCCDECA9400858BC9A36D5240A2965918F781F99D
19AT27C010@PLCC32.BIN	"RIPEMD (128 bit)"		020503B87627AA6745C78C559C5ED4CD
20AT27C010@PLCC32.BIN	"RIPEMD (160 bit)"		3F83FE819CDD97DF42E81C951A20AE252CC67C7A
21AT27C010@PLCC32.BIN	"RIPEMD (256 bit)"		3DF4709368C095DD924372491E9605D7CCAC8CC474649607D9B03CFC9F439F5B
22AT27C010@PLCC32.BIN	"RIPEMD (320 bit)"		07518EA26C6701AB55301D0EA6AF22E795BE47644E21FA0C4260D693E8E9AB1C693B94BBAD1C6984
23AT27C010@PLCC32.BIN	"Tiger (192 bit)"		9B1B69AA9A0B7A2647869EC2E8F13105B79A18640C431386
24AT27C010@PLCC32.BIN	"Whirlpool (512 bit)"		97CEA3129B43A6794439EFE185A87E2BC2CD11FFF4E246AFFD986B59E0AD168D6BC48DC8B2CBA5BB46C049E6A27A3D3D11F2AED4CDA99B3BB0E8B7D043D4C41E

Modified BIOS - Checksums

1Document	Algorithm	Checksum	Checksum/Digest
2AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Checksum (8 bit)"	26	1A
3AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Checksum (16 bit)"	53530	D11A
4AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Checksum (32 bit)"	10277146	009CD11A
5AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Checksum (64 bit)"	10277146	009CD11A
6AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"CRC (16 bit)"	1268	04F4
7AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"CRC/CCITT (16 bit)"	25252	62A4
8AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"CRC (32 bit)"	1008895062	3C228456
9AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Custom CRC-16"	1268	04F4
10AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Custom CRC-32"	1008895062	3C228456
11AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"MD2 (128 bit)"		DD9146053520CFCC8EDA4945720738EB
12AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"MD4 (128 bit)"		FCD29A3686F8BAD8912FAC6CDFDA7110
13AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"MD5 (128 bit)"		B09966D587315ED333F91F6952774F84
14AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"SHA-1 (160 bit)"		08A34C20BA723658990285186B12C83E9812E312
15AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"SHA-2 (224 bit)"		37D7E4CC9FEF318143AAB49AAAA1EF2C9919E4CD28B133CEDDBA688C
16AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"SHA-2 (256 bit)"		06287A2012866D0AAEB08B9401D9E6826FC97882D1440152DEFF564729006308
17AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"SHA-2 (384 bit)"		3A9A49E1A67D8ED298AC3CBD9838A756FB4666A1D3CB0A2722D3EF969EB05273F577D59EF4C0A1599EBC54166B2831D6
18AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"SHA-2 (512 bit)"		5C7D4BD4E754DAB946E37A64386197F6AEDB6E62DE57B6F6C7DF93765DD848039AD869D87744C9EA234F1084574662B6E56AA30808C972E1F57D3A11EA483051
19AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"RIPEMD (128 bit)"		CC09C36CD28F0634DDC33BA989CD0F56
20AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"RIPEMD (160 bit)"		CE966EB0819F7524C8B709404726154B2DAE1E78
21AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"RIPEMD (256 bit)"		3E4062EF74F025B300BD0D8E2E0B73803A9C46235410B0DBD6E25ADD5E2B13D7
22AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"RIPEMD (320 bit)"		0DDBBA983D919E6695C20B0670C5BB933D09B1978BBB6E789B8EEDB309A56E54B112ECDD14CFF0F7
23AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Tiger (192 bit)"		65444F9C9D1FE4CFD0D4440D0AF1A8648D30F7A9FE74D11B
24AT27C010@PLCC32_CRT_BOOT_DESC512KB.BIN	"Whirlpool (512 bit)"		1832E6372503B57F8A1BD6388BCCCC44AB8A576DB07CBB09738BF0A4F5E1AF695D3622790E75724CAC199F9733E7422A7BA7A2910F59DFF361A3D687AEF43182

Fixing the checksum of the modified BIOS
The next step is to re-balance the modified bios to trick or satisfy the checksum validation routine. The approach is doing this from the earlier articles (based on some googling) is to change the values of 'unused' or non important areas of the bios so the calculated checksum becomes the same as the original.

Original PC BIOS uses an 8bit checksum with the intended goal for the 8bit checksum to result in "00" (ie zero zero).

Here is a good worked example:
https://minuszerodegrees.net/misc/8-bit%20checksum.htm

BIOS Modification - Success
After few failed attempts, success at last with glorious CRT mode now properly enabled in the bios at boot.

I replaced the description of the LCD panel that briefly flashes up on boot with the name of video chip and the amount of video ram and adjusted a few values to restore the expected checksum.

Its nice finally resolving this, particularly for entering the bios screens and not needing to rely on the dos programs at boot.

Here's what the modified video bios looks like.

UPDATED to include pic of initial boot screen

And here is the additonal ' junk' hex values in red that were inserted to balance the checksum to make it pass the checksum validation. I changed 2 x hex value near the end of the video bios:
00 to FF
00 to E7

BIOS Modification - File Download
And....here is the modified bios file that i mentioned earlier to force CRT mode during Boot.

Parallel port (Printer etc) - Location
To complete mapping for this, HDR15 is the location of the parallel port pins (just below the CHIPS F82c735)

Added pic of plug in socket (which i didn't include for the prototype)

Power Supply - ATX Breakout board + cheap PICO PSU
To power the unit, i purchased one of these cheap ATX power supply break out boards off AliExpress and combined it with a cheap fanless 90W PICO PSU so i could run the whole thing off a 12v power supply adapter. I modified the breakout board to just use:

• 5V
• 12V
• -12V
• GROUND

Unscrewing the terminals and soldering a spare MOLEX cable directly to the board (to keep it from being bulky). These ATX break out boards are great for projects like this, even contain fuses, power led, and a power switch.

ATX Breakout

PICO PSU + ATX Breakout + Molex + Switch wires
I wrapped the molex wires in color codes to make sure i didn't mix up, and soldered 2 x wires under the ATX board switch so i could extend a power switch to the front of the perspex case. I mounted the PICO and breakout board under the ISA sound card given the amount of clearance / space under it and given i'm using an external 12v power supply.

I ended up buying a 12v 5A power pack but I don't think the board draws much at all as the 12v power pack doesn't create much heat all, other SBC from this era seem to draw 2.5A - but i haven't tested the power draw of it however it is very stable with 5A.

PC104 Add on Card - Network and extra COM port
While i'm including the remaining photos, i wanted to include a few details regarding this additional PC104 card that was specific to this SBC. Namely this included some clues to what some of the ports were (namely LEDS and Mouse) - as there are some parts of the pcb that re-use pins on the SBC. As mentioned earlier, the mouse pins didn't seem to register when connecting a ps/2 mouse and i ended up resorting to a ps/2 to serial converter.

This card adds:
- Base10 Network (J3 pins = Base10 Network)
- COM A and COM B pass through (COM A goes to another large IDC socket and COM B passes through to a COM B socket on the addon card.
- COM C (adding an additional 3rd COM port via the multi function IDC port)
- Multi Function IDC port (which includes COM A and appears to map the mouse pins)

While the BIOS and Windows 95 detects all 3 x COM ports, windows 95 also detected the network card (and automatically included drivers)- i could only get the COM ports working reliably - with the network pins not able to communicate (regardless how i reconfigured them). I suspect i might have either a hardware or driver conflict somewhere (DMA, IO address etc, or possibly the default win95 drivers isn't great for this card).

Given I've got all the functionality i need for now, i probably won't give this add on card too much more attention (that said if i do get the network working - i'll update this post).

Upperside of Add on Card

Underside of Add on Card

Floppy Port Location and Pinout
While I haven't used the floppy pins to connect a drive (given i'm using CF Card for IDE HDDS), I realised i haven't included the location or pinout from tracing through from the IC.

F82C735 Control Chip -Floppy pins

Floppy Location

Floppy Pinout

Driver Pack
Lastly, a driver pack with relevant video files and BIOS backup files in one nice single zip file from my trials and and tests.

Thermalwrong wrote on 2023-03-18, 19:53:

Thanks for sharing this, I had a similar problem with my Advantech PCA-6145 board which seemed to be set up with some odd settin […]
Show full quote

Thanks for sharing this, I had a similar problem with my Advantech PCA-6145 board which seemed to be set up with some odd settings for the last LCD it was connected to. I was getting the same thing you had, although I think I had all sorts of video trouble with the Chips control panel crashing the PC at some point.
I have two of them and compared the BIOS between them only finding a couple of bits difference so it was fixed easily enough, but it's likely this will work for most Chips & Technologies CT65548 equipped SBCs and maybe laptops.
Similar thing to here - you can use a crt.com file or debug commands to do the same, but having it in BIOS is nicer: Re: C&T 65550 CRT BIOS

It seems a bit odd that they went with an OTP EPROM chip for this system since the video BIOS does usually need modification for the SBC's application. Maybe that's not the original? Seems possible since there's no BIOS vendor sticker on there. I also have a PCM-4825 which uses a PLCC32 like your board and that's an SST 29EE010 on there - if the pinout matches maybe you could use an EEPROM instead now that you've got the T48 programmer.
Good luck with your ROM modifications with this board 😀 I really like the enclosure and setup you've got for it now.

excellent thread, i came across this by chance after spending a week+ trying to get my C&T 69000 based Dauphin Orasis tablet working again with its TFT panel.

i may be wrong but you might be able to substitute a 27SF equivalent eeprom for that chip and be able to erase/program it. should be a 27sf010

https://www.futurlec.com/Memory/SST27SF010.shtml

I did this in my ECU programing days to replace a 27c512

Sev80 wrote on 2023-05-17, 01:07:

i may be wrong but you might be able to substitute a 27SF equivalent eeprom for that chip and be able to erase/program it. should be a 27sf010

https://www.futurlec.com/Memory/SST27SF010.shtml

I did this in my ECU programing days to replace a 27c512

Thats excellent and thanks for sharing what to replace these eproms with (I still have a couple left from the recent batch) but it was getting a bit costly to prototype and that will be handy if need to make more changes un future.

For reference for anyone else looking for various rare legacy vendor utilities/applications (bios, video bios modification tools etc etc) the following is an exceptional download resource - and deserves to be mirrored somewhere:

http://ftp.emacinc.com/LegacyProducts/SBC/SBC-455/

You can navigate up a few levels to find various SBC setups ( ie that may have a rare chip that you need a file/driver for).

It was referenced in a post I linked to earlier but adding it here given its not easy to find.

dekkit wrote on 2023-02-18, 17:00:

Issues Extracting Phoenix BIOS […]
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Issues Extracting Phoenix BIOS

Using this entry to avoid anyone else wasting their time trying to extract/backup a Phoenix BIOS using the Phoenix branded tools available on the web.

(Please note this does not apply to 'Phoenix-Award')

After obtaining each version from:
https://www.wimsbios.com/phoenixflasher.jsp#gsc.tab=0

Its been disappointing to realise that the official utilities require you to have a 'new' valid bios file before it will allow you to proceed to the back up step (regardless if you have selected back up only or backup and flash) .

It seems the ' backup bios rom and then exit' use case wasn't considered.

Exploring the command line interface of both DOS versions and Windows versions suggests these switches should help achieve this (they dont!)

/BU <filename>
and
/RO <filename>

/BU is only really to determine the name of the backup file - before it tries to flash.

/RO is used to extract the one of the components stored within the bios backup file ie the flash data component. Correction - now that i have random bios file, it appears this switch is actually trying to save the internal bios to a specified file (but not write a new bios to the internal flashrom)

The bios backup files supplied by vendors look to contain 'data to flash' + 'information on how to flash it'. The RO switch looks to be more about extracting the flash part from a given bios package file. This is based on my reading of Phoenix utilities user guide found on the same site.

So now it looks like I'll need to find an external hardware bios reader thats compatible and maybe a few spare bios eeproms.

Also worth mentioning:
- behaviour of both windows and dos versions is the same (with switches and both requiring an input file)
- not a great deal of visual difference between the windows ones (although take note some dlls are missing in some windows packages but can be found in other ones)
- while the windows editions won't work in w95, they will work in win98 and newer.
- on windows nt 4, it seem to keep giving dll errors 'kept looking for powrprof.dll '

Haven't tried any other 3rd party bios tools As cant find any that support socket 3 era Phoenix bios but I think its likely safer to use.an external reader now

UPDATE #1
I found a random BIOS.WHP on the net that at least gets me past the Phoenix 'need' a bios file requirements of phlasher16 BIOS_WPH.zip
This was found in a CRISDISK package, which Ive since learnt is a method to rescue a bad bios flash on some motherboards ('Crisis Disk BIOS Recovery Boot Block') .
I've included it with this post, in case anyone body needs to use it to try and make a backup of their internal bios - but becareful!

While it got me through the first error, and enabled me to move to the stage of extracting the SBC's internal bios via phlasher16 - that stage of the phlasher16 crashed / froze the pc. So no luck for backing up the bios for now.
Have ordered a hardware device to see if i can read the rom (which is still a few weeks away)

Windows Performance on 486
Also to summarise my experience of playing around with installing windows on this 486 SBC (with 32MB ram, video card with 512KB ram)

Windows 95b = great /zippy
Windows 98 SE = sluggish / terribly slow /but usable
Win NT4 = works well similar experience to w95

So as per other posts on vogons - wouldnt go later than w95 on a 486.

so just to confirm, if you use phlash /ro, its not dumping the entire eeprom out? I do see when I run this the file size matches the rom size.