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Re: Automatically determining the A2 slot of a specific card.

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Hi Alex,

>Is is ok to poke each peripheral slot in an attempt to determine a cards id=
>entity?
>Does this have the potential to screw up the setup on other slotted cards (=
>I'm thinking about I/O cards because poking will be driving physical extern=
>al devices)?

The only thing I know for sure is that there are opposite opinions on
this topic.

My personal opinion:

The Cx?? space is supposed to contain ROM. So you are supposed to be
allowed to read from that area without fearing to cause unwanted side
effects. In contrast the C0x? space is supposed to contain I/O ports.
So even just reading from any of those 16 addresses can potentially
cause any side effect including e.g. destroying the content of an
attached mass storage device.

An example:

None of the three known Ethernet cards (LANceGS, Uthernet, Uthernet
II) supported by IP65 has ROM allowing to cleanly identify it. So my
strong opinion is that a program needs to ask the user for the slot of
the Ethernet card to use - and then IP65 can differentiate between the
three Ethernet cards by accessing their C0x? space - because all three
Ethernet cards are well known to tolerate those accesses.

Anyhow, in contrast ADTPro runs those IP65 accesses to the C0x? space
"blindly" on all slots. In a discussion on the topic David Schmidt
told me that he has never heard of those C0x? space accesses causing
any issue.

Regards,
Oliver

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Thread

Automatically determining the A2 slot of a specific card. Lukazi <lukazi@hotmail.com> - 2021-10-02 22:26 -0700
  Re: Automatically determining the A2 slot of a specific card. qkumba <peter.ferrie@gmail.com> - 2021-10-03 09:02 -0700
  Re: Automatically determining the A2 slot of a specific card. ol.sc@web.de (Oliver Schmidt) - 2021-10-03 19:56 +0000
  Re: Automatically determining the A2 slot of a specific card. Charlie <charlieDOTd@verEYEzon.net> - 2021-10-03 20:44 -0400
    Re: Automatically determining the A2 slot of a specific card. Michael J. Mahon <mjmahon@aol.com> - 2021-10-04 19:15 -0500
  Re: Automatically determining the A2 slot of a specific card. R.Kiefer.SPAEM@gmx.de (Ralf Kiefer) - 2021-10-05 14:54 +0200

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