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p89v51rd2 security

Started by lambros sirivlis, June 29, 2004, 08:41:08 AM

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Andy Ayre

Version 2.01 is now available that allows you to program the device even though security bit 1 is set. Thanks for pointing this out!

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lambros sirivlis

Thank you Andy.
it sounds great!!!
many thanks to you and to Eric for help.
Regards
Lambros

lambros sirivlis

hi andy.
2.01 works fine.

A small observation:

IF  clock bit was previously set and security bit unset

and you select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and 6 clocks/cycle
then  flash magic does not  set security bit.

You have to select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and "uncheck" 6 clocks/cycle.
Then  flash magic   sets security bit.

Can flash magic "first read" and then write  if a bit is not set?

Regards
Lambros Sirivlis

Andy Ayre

I tried this and I cannot reproduce it. When you choose "Read Security Bits..." from the ISP menu, does it show security bit 1 as being set?

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lambros sirivlis

1) select in step 4 of flash magic
verify after programming,
fill unused flash,
6 clocks/cycle
After reset magic flash shows correctly that
security bit is unset and clock bit set(6 cycles)

2) select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and 6 clocks/cycle
then flash magic does not set security bit.
(security bit is "unset")

3) select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and "uncheck" 6 clocks/cycle.
Then flash magic sets security bit.
Now security bit is set and clock bit is set.


Andy i'm not very shure about this cause i done this 3 steps only
one time with a single chip.
I'll try it again tomorrow.



regards
Lambros Sirivlis

lambros sirivlis

1) select in step 4 of flash magic
verify after programming,
fill unused flash,
6 clocks/cycle
After reset magic flash shows correctly that
 clock bit set (6 cycles)
security bit 1 is "unset" (correct)
my program runs ok

2) select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and 6 clocks/cycle
Message: Operation failed(programming security bit )

I read :
 clock bit set (6 cycles)
security bit 1 is "unset"  (wrong)
my program runs ok


3) select in step 4 of flash magic
verify after programming,
fill unused flash,
set security bit 1,
and "uncheck" 6 clocks/cycle.

I read :
 clock bit set (6 cycles)
security bit 1 is set  (correct)
my program runs ok

Maybe  flash magic (in my 2nd step) quits because has to set
an already programmed bit (clock bit)

lambros sirivlis

Andy,
if i'm not asking too much
can you add an  option to serial number window?

A box to check that says:
"Always use the same serial number".
And if you check this box flash magic after programming
automatically sets this serial number.
Serial number works like password so you can use the same
number  always.
(it's easier to remember it  if you want to unlock the device later)

Regards
Lambros Sirivlis

Andy Ayre

It appears the device is switching baud rate, so I've sent the problem to Philips for analysis.

I'll add your suggestion to our to do list. Thanks.

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lambros sirivlis