help Blow it not working

Thread Starter

mani_ps2

Joined Jun 28, 2008
1
i assembled the "blow it" programmer as in "board.jpg" in the ZIP file downloaded from http://www.geocities.com/dinceraydin/8051/.

and when blowing in real mode it shows as blowing even if the 89c2051 is not inserted in the socket.

this version uses BC548 instead of BC547. I have no idea to resolve this problem, can anybody help me. thanks in advance
 

bertus

Joined Apr 5, 2008
22,270
Hello,

I do not have any practical experience with this, but in my oppinion the BC547 and BC548
only differ in maximum voltage.
Perhaps the HFE (gain) of the transistor is to low.
There is nothing said about the HFE of the transistor, an C type has a higher HFE than the B or A types.
See datasheet.

Greetings,
Bertus
 

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beenthere

Joined Apr 20, 2004
15,819
All the transistors are doing is pulling a line to ground. Almost any NPN transistor with a beta of 100 or above should do as well as the type shown.
 

SgtWookie

Joined Jul 17, 2007
22,230
The "Blow-It" board and software is rather simplistic. It has no provisions to check whether or not you've actually installed the uC to program; it simply sends the commands to the board.
 
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