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· Hardware
#BRIDGE/EMS
7 messages in this thread
I had the opportunity to borrow an emm card, and I discovered the
same thing (no 2nd serial port). I'm pretty sure it's due to the fact that
the serial port IRQ's and I/O port addresses are used in a non-standard
way… notice that when the bridge boots and reports on # of serial &
parallel ports the address given to LPT1 is listed as $278, which is really
the address for LPT3. The really wierd thing is that although COM1 is listed
at $3F8, running ATITEST or similar equipment test routines report a serial
port at $2F8, which is COM2's address. I think the problem is that CBM
planned to do serial port emulation and abandoned it without restoring things
to normal. If this is the case, there may be a software fixfor this. If it's
that they needed an IRQ for something else, they should have used IRQ2, which
is generally unused in an XT. Sure wish CBM would post a listing of any I/O
addresses, etc they are using!
I believe that someone from CBM posted a message that they are using
the COM2: interupt for JANUS (the PC <–> Amiga interface).
Wish I saw that message! It is my under standing that the keyboard
and serial emulatin are tied together, and are controlled by the same
register(s) that enable/disable parallel interface emulation. What doesn't
make sense though is that in the Bridge info I have (taken from the
A2000/500 tech manual) if you have one, you _SHOULD NOT_ have the other, so
if the keybd/serial mode is enabled, why does a parallel port show up?
Maybe if there is a JANUS upgrade, things will get straighteded out. Still
feel they should have used IRQ2 though. As an aside…do you know if the
new Lattic C package or MANX's latest have the JANUS stuff? Mark
No idea on Manx having JANUS library routines in them…I've got
Lattice v4.0 and don't see anything in there about them. JANUS 'says' that
there's a printer there….the program LPT1 'plugs it in'. It's the same
thing as if you had a parallel port on a PC but nothing plugged into it.
The port is there…the printer isn't. I've got my expansion board set as
LPT2: and it works fine that way.
No idea on Manx having JANUS library routines in them…I've got
Lattice v4.0 and don't see anything in there about them. JANUS 'says' that
there's a printer there….the program LPT1 'plugs it in'. It's the same
thing as if you had a parallel port on a PC but nothing plugged into it.
The port is there…the printer isn't. I've got my expansion board set as
LPT2: and it works fine that way.
Wish I saw that message! It is my under standing that the keyboard
and serial emulatin are tied together, and are controlled by the same
register(s) that enable/disable parallel interface emulation. What doesn't
make sense though is that in the Bridge info I have (taken from the
A2000/500 tech manual) if you have one, you _SHOULD NOT_ have the other, so
if the keybd/serial mode is enabled, why does a parallel port show up?
Maybe if there is a JANUS upgrade, things will get straighteded out. Still
feel they should have used IRQ2 though. As an aside…do you know if the
new Lattic C package or MANX's latest have the JANUS stuff? Mark
I believe that someone from CBM posted a message that they are using
the COM2: interupt for JANUS (the PC <–> Amiga interface).