Problem ISP 89lpc921

[Chance]

I am using 89lpc921 without revision number and Flash magic ver.1.81.
New device is going into ISP mode by means of 3 pulses on the RST pin.
But after programming without erasing the Boot loader area (0xC00-0xFFF)
hardware entry to ISP mode not operate.
Only enable the break detect in my code and then sending Break Condition
forced device into ISP mode.
What's wrong of the LPC921?
What if is situation when the device is not operating properly or the serial connection is not reliable?
Help me.
Thanks.



Post Edited (11-09-03 22:04)

[Chance]

Hi, Andy!

My problem is not interesting for you probably (?).
I by itself has solved it's.
The minimum value for '/RST HIGH time' in ISP entry waveform after programming is not 1 microsec.

My tests showed (on-chip RC oscillator mode):

for lpc932 is 2 microsec
for lpc921 is 3 microsec

Regards

[Chance]

Hi, Andy!

How to calculate 32-bit CRC result?

Thanks.



Post Edited (11-11-03 01:17)