Some firmware Q2E24 nand blasting results

Mitch Bradley wmb at laptop.org
Fri Dec 12 04:26:42 EST 2008


Gary C Martin wrote:
>
>
> Q2E24 general observation: First key press at ok prompt is dropped 
> (kept catching me out and making initial typos) not sure if this is 
> worth a ticket.
Here's my guess for what is causing the "loss of first key":

To get to the ok prompt, you have to type to ESC key.  That could be 
interpreted one of two ways:

a) Press and immediately release the ESC key

or

b) Hold down the ESC key until you are sure that OFW recognizes it.

In case (b), the keyboard auto-repeats the ESC char so OFW sees N 
repetitions.   The "type ESC to interrupt" handler takes the first one, 
and the next N-1 repetitions go to the normal OFW command line editor.  
ESC is a prefix char for editing commands like "delete word" - the 
editor generally follows EMACS conventions in that respect.  ESC-ESC is 
an unimplemented command, so nothing obvious happens for paired 
ESC-ESC.  But if N-1 is odd, the "left over" ESC puts the line editor in 
"waiting for the completion character for the ESC prefix" state.  So the 
first printable character you type is taken as the completion of the 
ESC-<whatever> command.  Even if that first character represents a valid 
editing command, you aren't likely to notice its effect, since the 
command line is empty at the time, so the editing command has nothing to 
do - no word to delete, no place to move forward or backward, etc.

I never have this problem because I don't hold down ESC, I just type it 
once.  As it turns out, the startup jingle is a good marker for when OFW 
is ready to accept the ESC - as soon as I hear the jingle start, I reach 
for the ESC key and type it once.

Mitch




More information about the Devel mailing list