>PIC17C4X that loads a .bin file from serial, and put it on external RAM.

Miguel,

I hope your program is executing from a different part of memory.  The
PIC17 chips can program themselves using the table write commands.  You
need to have the external ram at a different address during this operation
for it to work properly.

Otherwise, you may be programming the internal ROM.  Just because Vpp is 5v
doesn't mean it won't try to program - it just won't program reliably!

>        I think that then RAM -100 -120ns that i'm using are too slow for
>PIC17C4X.

Microchip recommends 100nS chips for 20MHz part.  If you look at the timing
diagrams, they are 2 clock times wide.

Andy

==================================================================
                     Andy Kunz - Montana Design
          Go fast, turn right, and keep the wet side down!
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