"Page, Curt S" <[EMAIL PROTECTED]> wrote in message
news:33818@palm-dev-forum...
>
> I have looked at some of the stuff handspring has posted. In my situation
I
> am not accessing any external ROM/RAM on the module, instead im looking to
> look directly at the data pins on the springboard connector. I have yet
to
> find a code sample or documentation that explicitly states how to directly
> read from the data pins. Actually I was kind of hoping that there were
> functions similar to InP( ) and OutP( ) for the palm OS. Perhaps Ive
> missed something in one of the SDK documents.
>
> Thanks for the suggestion, any and all help is greatly appreciated.
My understanding is that the data lines are directly connected to the
processor bus, and all I/O to a Springboard module is done through
memory-mapped I/O. The 68K doesn't have IN/OUT instructions, you just read
and write from specific memory addresses, and peripherals share the same
memory space that RAM and ROM use. This varies from the Intel chips which
have a separate I/O space. Those data lines correspond to D0-D15 from main
memory, with the address detection login on the Springboard module
responsible for making sure they aren't driven except when the module's
addresses are asserted. If you had a module that puts signals out on D0-D15
even when the addresses weren't selected, you could prevent running of any
code on the device by interfering with instruction and data fetch by the
processor.
--
Ben Combee
Veriprise Wireless <http://www.veriprise.com>
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