[Flashforth-devel] FlashForth V3.6 PIC18F4550

[R. M. H. <in...@ib...>]

Hello Mikael,

here my answers for your latest questions. The
history of choice for a Pic18f4550 was the hardware
interfaces for A/D, PCM, I2C and at this time USB.
Flash, ram and eeprom seemed adequate. No time to
lose and a cheap C-compiler(sourceboost) on the
hand – quick start.


* Have you tried many different chips or just one ?
Yes, I have used about 30 different pieces of 4550.
Their are 12 working systems as prototypes since
last weekend by the customer ( limited function).

* Have you tried other UART speeds 4800 9600 19200 38400 ?
No, because I didn't ever see the special characters,
you describe under “Problems”. To me, the problem
seemed not the data transfer(input buffer/processing)
but rather the compiling process as it works. One source
give always the same result (with or without any
transmit delay in TeraTerm). The basic functions of
the hardware (all implemented at the begin of flash)
will always work as intended.

* Have you tried to blank the chip and reflash FF ?
Yes, some times without any problems. In the begin
of prototyping I didn't understand the ESC start
(lot of ESC no cr) right and therefore I used reflash
in my desperation.

* What is your clock speed ?
24MHz internal / external oscillator 24Mhz or 12MHz

* Have you tried lower/higher clock speeds ?
No, because their was in the time of debuging
of the basic hardware no reason and now I can't
see the mechanism of impact at the Problem.


Gruss - Robert