I am programming AT89C2051 in uVision2. I am using programmer PG302. When I flash controller with hex file created using Assembler, everything is OK. But when I flash controller with hex file created using C51, I get message "Device not equal to file" (in PG302). I don't know what to do, please help if you know how. (My C51 code is OK, error is probably in created hex file, because it is about 3 times bigger than file created using Assembler (for the same function)).
Are you using the free Evaluation tools? If so, did you read the Limitations: http://www.keil.com/demo/limits.htm
If not the Eval tools, do you use printf?