>1. You have already downloaded the >flash2.hex inside 8252 and now you >can't overwrite with the new one ?.

yes

>2. At which COM port is attached your >mouse ?

my mouse is over PS/2 connect...

>What kind of downloader you use

TASMedit

>and what programming mode: serial or >parallel.

serial

>Which PC device the data comes from: >COM port or parallel port ?

COM

>Are you sure that write lock bits >haven't been enabled at the time when >you downloaded first time the >flash2.hex ?

no - i am not sure... this are my
first steps :-)

>And if they have been enabled, are >you sure that the first operation >which start the programming process >is Chip Erase ?

no too - not sure

>Since you use serial downloading >method are you sure you follow the >serial programming altgorithm in the >right sequence ?

i don't now :-(

You wrote:
If i make a reset of the 8252 the PC works

>the first step in serial programming >altgoritm is setting RST pin to high.

right...

>(Now I'm wonder how you set this by >hand, what the logic level you apply >to RST pin and how is wired the PC >command downloader to your target >device)

i have on my flash-board two pin's
for reset ... if the PC send data
to the 'COMM2' on my board the RST
is set automat.

>Your mistake is that you use P1 port >as flashing your bits in application. >The downloader use it too. P1.5 like >MOSI, p1.7 like SCK.

right - i have in the moment of sending
the code not think on this.....

>Maybe your downloader is unable to
>raise the RST pin to high and the >8052 is running your application as >time you try to download.

no - a) i can set the RST by hand AND
b) the board do it autom. .

>Change in flash2.asm the port P1 with >P2, compile, download serial the >program and see what happens. Just
>for test.

ok - i test it now...

>For future: [...]
thx for this!!


so --- my last 'exit' is to sending
data parallel ???

the 8252 never loss the program ???
(of curse without power)...???

cu
Thorsten