Parados Dual OS Eprom Writing Error

[unay]

Hi all,

I'm trying to switch Parados Dual Os.
When i try to write dual os image on eprom i'm getting the error belowe.
İs any one know abot this error, and what can i do?
I'm trying to use file on the link.
File:DualOS.ROM - CPCWiki



"Programming FLASH ...
ERROR!  Address:0x000004  Buffer Data:0x72  Verify:0x70
Programming  ...Failed"

[McArti0]

Bad chip?
To fast write?
Bad connect?
Bad programmer?

[unay]

chip is 256k, 16k bios can write without any errors.
only 32k dual parados bios cant write.

[eto]

chip is 256k, 16k bios can write without any errors.
only 32k dual parados bios cant write.

The file has 0x72 at address 0x00004. So if your programmer writes a 72 but then reads a 70 then it's a problem with the Eprom or your programmer but it can't be a problem of the file.

What chip is it exactly? (exact model number)

Was the Eprom properly erased between programming attempts? Can you program other 32K files properly?

I also assume it's inserted directly into the programmer without any adapter?

[unay]

The chip number is M27C256B.
I was trying some various ways, eventually it works.
Dont ask me how

Thanks.

[Bryce]

The chip number is M27C256B.
I was trying some various ways, eventually it works.
Dont ask me how

Thanks.

Probably just a bad connection between the EPROM Pins and the programmer. Happens often with older EPROMs.

Bryce.