Main Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - Francesco

I found the problem. The psen pin was not joninted with the iron, i found it only with the dvm as you suggested. I am sorry. Thank you very much for your support. I just started yesterday to enjoy my first 8051 based circuit.
Thank you again.

Francesco Fontana
No way, I followed the instructions in the errata sheet about P89C51Rx2 page 3 i guess, title:


I did the connection as shown in the two circuits. Vpp pin connected to +5 throw a 3,3 K resistor and to ground throw a 10 uF capacitor. And i connected Psen pin to +5v throw a 10 uF capacitor and to ground throw a 3,3 K resistor. The circuit of the the reset pin is the same of the an461 i only used a 4148 diode instead of the one used in the circuit. The cristal is a 12 MHz. In the meantime i "burned" another chip with a program that make the led blinking just to be sure that the circuit is running the program loaded. Should i increase the value of the two 3,3 K resistor to a 33 K as i read somewhere in the forum. May i send you the schematic of the circuit i am using?

Thank you

Francesco Fontana
Old Topics / ISP problem with P89C51RC2BN and Flash magic
November 21, 2004, 05:21:32 AM
I managed to download a simple program in a   P89CRC2BN using Flash magic but now I can