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???
01/02/12 10:35
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 		 #185247 - Your schematic is wrong
Responding to: ???'s previous message
Remove the transistor switch in the VCC line. Or turn it on permanently.
Copy the RESET circuitry from the data sheet. e.g. capacitor between RESET and VCC, resistor from RESET to GND.

Alternatively use a proper external RESET supervisor chip.
There are several ways of wiring an 8051 RESET. Copy an existing proven design.
I doubt that your schematic would work reliably.

The AVRISP-2 should program a AT89S52 just fine.

Connect all 6 ISP wires to the relevant AT89S52 pins.

The AVRISP-2 will use the active-high RESET. You should read signature successfully with ISP frequency of 200kHz or less.

David.

List of 32 messages in thread
TopicAuthorDate
AT89S52 and ISP problem            01/01/70 00:00      
   Quick Schematic Obversation            01/01/70 00:00      
      hmm            01/01/70 00:00      
         Your Reset Input            01/01/70 00:00      
            Thanks!!            01/01/70 00:00      
   Your schematic is wrong            01/01/70 00:00      
   The AT89S52 needs a reset chip!            01/01/70 00:00      
      The AVRISP-2 is a USB device            01/01/70 00:00      
   what an AWFUL design            01/01/70 00:00      
      Isn't mine!            01/01/70 00:00      
         Compare several schematics            01/01/70 00:00      
            Thanks!!            01/01/70 00:00      
               Sink or source? Does matter a lot!            01/01/70 00:00      
                  Not granted            01/01/70 00:00      
                     Processor can be used            01/01/70 00:00      
                        Yeah..            01/01/70 00:00      
                     cure for ignorance            01/01/70 00:00      
         you forgot the quotes            01/01/70 00:00      
         well            01/01/70 00:00      
            Funny            01/01/70 00:00      
               RC resets are evul            01/01/70 00:00      
                  So?            01/01/70 00:00      
                     Not necessarily,,,            01/01/70 00:00      
                     I guess you are a student / hobbyist            01/01/70 00:00      
                        Oh..            01/01/70 00:00      
                        Even or better just then...            01/01/70 00:00      
                           Where to apply 100nF?            01/01/70 00:00      
                              Shortest possible distance            01/01/70 00:00      
                        especially not for a hobbyist            01/01/70 00:00      
                  RC RESET worked fine for years ,,, but ...            01/01/70 00:00      
               no, not "will" but "is likely to"            01/01/70 00:00      
                  an added IMPORTANT comment            01/01/70 00:00      

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