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Need help when use isa-to-usb card in IBM 5160!

The boot bios is quite simple,it's 8086 instructions compatible.When it's been called by system bios as option rom, it replace the int 13h and int 19h with its own routines.
NEW_INT13H emulates hard disk with usb flash drive.
I think it is where the incompatible problems come from.

code.jpg

Some delay code:
code2.jpg
Maybe delay code means to adjust cpu and usb disk?
 
Do we have the source? Surely the answer is to put the read/write routines into the XTIDE-UB.
 
Yes, I think the XTIDE Universal BIOS could support this controller, with some work.
 
pearce_jj said:
Yes, I think the XTIDE Universal BIOS could support this controller, with some work.
Click to expand...
Anyone who want to research the bios code or develop a new bios,I will send you the source code and my Ida pro disassemble project.
Hope the greate guys who develop XTIDE BIOS may pay attention on this card,I already send a email to them.
 
Please send me the code, maybe a Dropbox link or mail me via my site. Re flash, there is likely no way to program it unless the card has routed MEMW to the socket.
 
The current board from china is designed for a 32KB 27C256 EPROM and doesn't have MEMW connected.
So the 64KB W27C512 you have now is only used half.

The easiest way to change it is to use a 28C256 EEPROM and connect pin 1 of the 28C256 to socket pin 27.
Pin 27 of the 28C256 can then go to the MEMW pad on the ISA card connector.

Attached is the original schematic and modified one with the fixed address decoder.
 

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pearce_jj said:
Please send me the code, maybe a Dropbox link or mail me via my site. Re flash, there is likely no way to program it unless the card has routed MEMW to the socket.
Click to expand...
As soon as I go to my office I will send you the sourcecode.
It is worth mentioning that the sourcecode is a little different from the bin file I dumped from onboard rom.If you have IDA Pro disassembler,you may want to see the bin file too.
 
pietja said:
The current board from china is designed for a 32KB 27C256 EPROM and doesn't have MEMW connected.
So the 64KB W27C512 you have now is only used half.

The easiest way to change it is to use a 28C256 EEPROM and connect pin 1 of the 28C256 to socket pin 27.
Pin 27 of the 28C256 can then go to the MEMW pad on the ISA card connector.

Attached is the original schematic and modified one with the fixed address decoder.
Click to expand...
Very professional! Now the card works fine.
 
I just read through this complete post regarding the installation of USB ISA card in a 5160 system, but the post did little to answer the OP's original questions, and raised more questions than answered; at least in the way USB works with the 5150's and 5160's

Here's the issue as far as I can tell. First, are the mother boards compatible across the IBM line. If not, what will I need to purchase in order to add a USB ISA card in a 5150. I will also be using the adapter connected directly to one of two IBM 5161 Expansion Units.

If there are no additional requirements, then after assembling the ISA adapter, I will be simply installing the USB filter by adding the card and installing the drivers.

As always, I await your reply.

Cheers!

Thomas
Eugene OR 97401
 
People here did help me a lot.When I first got this card I can do nothing about it,only seen a lot of errors output(it's because of the bad address decoder,and 2kb aligned option rom problem).

Also I can use a 3.5" floppy drive now,before that I can't transfer any data to 5160 . So I load the ch375 dos driver,and it works correctly.

But what I really want to is making the old PC boot from a usb drive.The card's BIOS has some problems,it don't emulate hard drive properly.
Till now I can load a freedos kernel rightly ,but the file system seems not alright,the kernel can't find command.com on disk,so it stopped and wait for user input the path of command.com.I am still working on it,trying to fix the BIOS.As far as I know pearce_jj and pietja is working on it too.

To your question,I guess this card can work correctly in 5150/5160 or other 8 bits isa bus PC if your don't want boot from usb drive.You just need to plug the card and load the dos driver in config.sys,then a drive will be seen in dos shell.

edit:command.com not found.
 

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Last edited:
GOOD NEWS!
After a little hack to the bios rom,I successfully boot my IBM XT from usb drive.The bios has a defult CHS value for hard drive,which is used to convert address from chs to lba.
What I do is change them to a reasonable value,former value set was strange.
Anyway after so many tries,we can boot from usb drive now.And all my usb drive will work with this card.
When I finish some tests I'll upload the modified bios rom.
 

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This is the modified bios rom, it's not perfect but it may work in some situation.
I ran the Disktest.com writen by pearce_jj,but I don't finish the test,it runs for along time.
fdisk.com don't work with this card,it can't detect fixed disk.and if you use a large partition,dir command will take a long time too.
 

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Hello All,

Is someone presently working on an upgraded version of this card ?? i.e. full address decoder, "writable" EEPROM and such ??

On side : Is there any "interest" in buying some original cards, which seems not so easy .... going thru import agents and so .... given that the original card has to be "quite" modified ....
 
Gerardcjat said:
.......
On side : Is there any "interest" in buying some original cards, which seems not so easy .... going thru import agents and so .... given that the original card has to be "quite" modified ....
Click to expand...

I'd be interested depending on price, If I've read the thread right you can use the card as is and just use the Dos driver ?, Though to actually boot from the card in an XT it needs modding and a working bios. I sent yisung an email a while back regarding these cards and they replied 3 weeks later which didn't feel me with confidence, For the card it was $25 and $35 shipping to the UK and discount for quantity but i never followed up.
 
The original card from china can be used without modification using the driver in config.sys
If you want to boot from it you need to modify the card or place the boot ROM on another card (network, XTIDE and others)

Do know the current bios is just a modified version made by ineverland and has no guarantee whatsoever.

I got my card using a taobao agent, the longest wait was from china to me.
Also the bare chips and development board are available on eBay for a couple of dollars including shipping.

pearce_jj also hase a basic card designed, so the only thing stopping us now is a good stable opensource bios, preferably included in the XTIDE Universal BIOS.
 
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