Hi, I'm using an 89C51RD2 chip and an Texas Instruments TL16C754B Quad UART chip for serial communication. At power-on, a random character gets transmitted on all 4 channels of the UART. Can someone please tell me why this may be happening and how to prevent it? Thanks and warm regards, Sundeep
A invertor is connected between the uC and the ADM709 circuit. That, I believe is your problem. As the Power is ramping up a supervisor behaves in a predicatble way, an inverter behaves any which way it wants till its minimum operating voltage is reached. I have seen this design resulting in too short and/or erratic reset pulses. Get a reset high supervisor and use it. Erik
Thanks Erik. I think this is the problem too. -Sundeep