[Flashforth-devel] FF37 USB on 18F14K50

[Mikael N. <mik...@pp...>]

Hi Attila,

It should be possible to make FF3.7 run on the 18F14K50.
Propably the USB lib must be recompiled.
I did not publish the USB lib source, since it has the
Microchip copyrights on it.

A different ram memory map must be defined in the linker
file. And some addresses in the FF3.7 assembly source
must be changed to match the new HW.
At least the dual port USB ram is at a different address.
Also the Forth variables and UART buffers, which are now located above 
the USB ram in 2550, must be relocated back to $f060-$f200 area.
The USB ram will be at approx. $f200-$f230. So actually
some the Forth variables and UART buffer can better be placed at 
$f230-$f2ff.

I remember running a BG task blinking a LED on a USB FF3.7. That
was without a USB connection. But I am not quite sure
if it works now or not. I dont have any HW for that right now.
Maybe you can just try it.

You could also make a turnkey word which revectors key key? emit
to rx1 rx1? tx1. Then you can use the UART.

Cheers /Mike


 > From: attilaherman
 >
 > Hello Mikael!
 >
 > Thanks for the FF37!  I am using it successfully on 18F2550 with USB. 
 > It is fast and stable.
 > However I have two questions:
 > - I would like to use FF37 in USB mode on 18F14K50, but currently it 
 > is not supported.
 >  I know that, its 16kB memory is a bit slim, but it seems enough for 
 > some simple applications.
 > - Sometimes would be nice to use a controller (with FF37 in USB mode) 
 > without permanent USB connection to PC.
 >  Is it possible?
 >
 > Regards
 > Attila