problem with 18f4550 and E-blocks

samux · Post by **samux** » Sat Mar 10, 2007 2:25 pm

Hello
Sorry but I don't speak english very good...
I have already program the 18f4550 with the board but I want to re-program the pis and I have the message "the voltage is too low". I ignore this warning and the board don't recognise the pic and I have the message "Could not ID the onboard chip assuring it is the one specified in the configuration screen, i.e PIC18F4550.
Somebody knows this problem ?
thanks in advance

samux · Post by **samux** » Sun Mar 11, 2007 11:09 am

sorry but my board is : HP-488-00-3

Post by **Benj** » Mon Mar 12, 2007 10:16 am

Hello Samux

Are you using a Power supply to power your HP488 or are you using the USB supply. If you are using the USB supply and the LVP mode has been disabled in the PICmicro then you will need a Power Supply to re enable the LVP mode.

samux · Post by **samux** » Mon Mar 12, 2007 5:11 pm

Thanks Benj for the answer
I use a Power supply with jumper J29 in position "PSU", J20 in position USB and a jumper in position I/O.
When I want to use the LVP mode windows says an error.

Post by **Benj** » Tue Mar 13, 2007 11:03 am

Hello Samux

What voltage PSU are you using. It needs to be between 12 and 14 Volts. Also have you tried replacing the PICmicro as it may have become damaged.

samux · Post by **samux** » Tue Mar 13, 2007 5:18 pm

Hello Benj
the voltage is 12 Volts. In fact I have already use the board at school with a computer (windows 2000) and at my house (with windows xp sp2), I don't arrive to program the 18f4550. I will can know if it still work at the school Thursday.

Post by **Benj** » Thu Mar 15, 2007 1:01 pm

Hello

I have had a similar problem with these chips.

I think that the Code Protect gets set automatically in the PPP configuration so if you program with this setting enabled then the PIC is no longer able to accept write instructions. I could be wrong about this but when I manually set this to disable the chips were lasting more then one program cycle without complaining.

samux · Post by **samux** » Tue Mar 20, 2007 5:19 pm

I have a bad news : the board died. We don't know why the board doesn't work any more but it was under garantee...

Post by **Benj** » Wed Mar 21, 2007 2:09 pm

There have been a few reports of the PPP chips blowing. The best thing you can do is to return it to the supplier you got the board from and then we can take a look at it and replace any parts that have stopped functioning.