hi all... i am working on a project where i have to use SMD 44 pin TQFP SST89E516RD2 microcontroller. i am using TTL converter to program this controller using RX and TX pins. but i am not able to program the controller. i am using flash magic to program. when i press start button from the software it says RESET TO ENTER ISP MODE. but when i reset the controller, nothing happens. i have checked all the connection and also the connectivity. connected RX pin to controller TX pin and TX to controller RX pin. also only TX led glows in TTL converter. i tried changing around 4 boards but non of them are working. but the same if i try programming the DIP package, it programmes without any error.
how can i compare the signal behaviour between both of the contoller (DIP and SMD). because SMD controller does not send any signal back to the TTL converter. what i have noticed that using DIP controller. when i press start button from flash magic software, the TTL converter send 'U' to the controller and controller acknoledge its back and then i have to press the reset switch from the controller to enter the ISP mode. but in SMD controller when i press start from the software, the TL converter sends 'U' to the controller, but controller does not responds to it and stays ideal and does nothing.