Re: [Amforth] Development request

[Matthias T. <mt...@we...>]

Mikael,

>> >From checking your code, I can imagine a few things that would break
>> FF as well. ;)
> I am interested to know what that could be.

In flashforth.asm I found the following lines

        rcall   DOLIT
        .dw     dp_start
        rcall   FETCH
        rcall   TRUE_
        call    EQUAL
        call    ZEROSENSE
        breq    WARM_3
        rcall   EMPTY
WARM_3:

I read them as "if dp_start is -1, call EMPTY, otherwise
skip to WARM_3". This checks if the EEPROM got erased. Fine
so far (a common error if you forgot to flash the eeprom
hex file). But what if dp_start is something else?

I did not analyze (or even tested) this, but an invalid
turnkey action (e.g. assigning not an XT to turnkey) may be
sufficient (dp_start seems to be the turnkey vector). Than
you have no chance to recover the system automatically. (or
you have some more lines of defence...)

> I guess it can break but remarkably seldom.

Well, seldom is a relative number ;)

You check for errors, that already happened or are
possible. Its the same with security: You can do a lot
of things but someone will break in nevertheless. That
doesn't make your work bad, absolutly not!! I'm the one
who is lazy and ignorant I put all the burden to the
user ;)

Matthias