AVR-Chat

Hi Guys,

I have a small hobby project (Model Railroad DCC Accessory Decoder for
signalling) that basically need to use 2 pins for comms and 4 pins to drive
3 or 4 single color LEDs or 2 bi-color (red/green) LED's - so I would like 6
I/O.

Now with the AtTiny85 I can get 5 I/O easily if I use the internal RC osc,
which is fine but I'm wondering about using the /Reset line for the last I/O
pin that would be "nice-to-have"

My real question is how easy is it in practice to configure the Dragon or
JTAG MkII to reconfigure the /Reset pin all the time using HV ICSP so I can
develop/debug the code while the /Reset line is used for I/O as well as
debugWire?

Is this a good idea or not? 

I could only use the /Reset pin for an infrequent use that I can live
without while developing and then re-enable when I'm done if that makes a
difference.

Comments?

Regards

Alex Shepherd

Alex, maybe you could use some analog switch for choose when you want 
to program or when you want to use it for I/O or even use just some 
jumpers to enable the HV ISP. It will be like a swicth....

I think that it would work fine...

Bruno


--- In AVR-Chat@yahoogroups.com, "Alex Shepherd" <lists06@...> wrote:
>
> Hi Guys,
> 
> I have a small hobby project (Model Railroad DCC Accessory Decoder 
for
> signalling) that basically need to use 2 pins for comms and 4 pins 
to drive
> 3 or 4 single color LEDs or 2 bi-color (red/green) LED's - so I 
would like 6
> I/O.
> 
> Now with the AtTiny85 I can get 5 I/O easily if I use the internal 
RC osc,
> which is fine but I'm wondering about using the /Reset line for the 
last I/O
> pin that would be "nice-to-have"
> 
> My real question is how easy is it in practice to configure the 
Dragon or
> JTAG MkII to reconfigure the /Reset pin all the time using HV ICSP 
so I can
> develop/debug the code while the /Reset line is used for I/O as 
well as
> debugWire?
> 
> Is this a good idea or not? 
> 
> I could only use the /Reset pin for an infrequent use that I can 
live
> without while developing and then re-enable when I'm done if that 
makes a

> difference.
> 
> Comments?
> 
> Regards
> 
> Alex Shepherd
>