[aprssig] TNC220 ok for UI-DIGI ?
ron.stordahl at digikey.com
Fri Mar 11 14:29:28 CST 2005
Mark et al
Does the Tiny-2 allow one to address the entire 27C512 as does the
MFJ1270C with appropriate jumper settings? Or do you have to bend pin 1
of the eprom out and wire it to pin 16 on the Z80 SIO chip? This is
done to allow the entire address space to be used when using The/Net
X1J4 firmware which outgrew the space of a 27C256. It's something I am
wondering about as I am speculating that someday this might be
required. Perhaps UIDIGI will outgrow the 27C256 for example. Or since
the source to The/Net X1J4 has been released, perhaps it could be made
into a 'new paradign' digi plus node.
I do believe the Tiny-2 has jumpers to permit you to select the lower or
upper half of the 27C512, so that for example you would have the
factory software in one half, and UIDIGI in the other. This is useful
because UIDIGI does not have a CAL function.
Mark Earle wrote:
> At 05:04 AM 3/12/2005 +1000, you wrote:
> >Whats constitutes a TNC2 Clone ?
> These days, that would be:
> 1. Genuine TAPR TNC-2 (almost impossible to find)
> 2. Pac-Comm Tiny-2 or Mark-2
> 3. MFJ 1270 series.
> We've used the Pac-Comms with good success. I prefer them over MFJ,
> because the MFJ has a "tuneable" modem, and may drift at sites with
> wide temperature variations. The modem chip used in the Pac-Comm is
> crystal referenced.
> ) ) de WA2MCT Mark
> ( (
> ) ) You will be assimilated... oooh, coffee!! EL17HQ
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