8255 manufacturer detection

[issalig]

Hi all, I am messing around with Amstrad Diagnostics and included some new functionality such as motor tape/disk, z80 cmos/nmos/flavor and rpm (not still working the shamelessly robbed code from Brice Rive's RPM)

I have read that 8255 manufacturer can be guessed but I do not know how and I would like to include it in the diagnostics.
 According to cpcwiki "It is possible to detect each version by writing and then reading from the ppi control i/o port. Each can give a different pattern of values that are read back. " <- https://www.cpcwiki.eu/index.php/8255


Any hint?

P.S: You can check my contributions in https://github.com/issalig/amstrad-diagnostics/

[Pollo]

I don't know but for info, this line was added to the wiki by Arnoldemu in 2011:  Difference between revisions of "8255" - CPCWiki