I'm using 89C51RD2 in my circuit. When i power on the device, the device functions properly as desired. But when i give a manual reset to the device, without switching off the power, although it functions properly but some erratic behaviour is observed periodically.
Can anyone tell what could be the problem or if i'm missing anything in initialising the device.
You need to elaborate your problem. What kind of erronous behaviour do you get ?
It can be that your reset circuit is not set up correctly.Check out the Image I am posting showing an example of reset button with 89c51.
Also the 'unusual behaviour' could be due to the fact that your microcontroller is damaged.
Hi,
try to monitor RESET line and power supply. In my previsious design I've used a MAXIM (MAX691 if I remember correctly) dedicated IC to generate reset pulse and monitor vcc line and I solved all my problems.
For example if a spike increase vcc, 89C52 will do strange things!