Hi Jan,
No it doesnt work,
I dont know why the method doesnt work. The characters recieved via UART are recieved at the part of ISP and at that point I just XOR it with a for the outside world unknown digit. The ISP first recieves it, or it is a command or ":" or other ASCII character, first of all i XOR it with a number, even then, the ISP is flashed into the LPC with flash magic, flash magic even verifies to type YES if want to currupt or modify the ISP-code. FM gives no errors and the program i run works. But after i enter ISP again, FLASHMAGIC should not communicate with the LPC because the protocol is now changed, so now if FM sends one character, the ISP should see it as a different character(XORed with a digit) and that does not happen, FM communicates perfect, and even flashes the program HEX perfectly. I dont know what else i should change, am flashing the ISP correctly, is there anything else i did not see?
here is the code i changed,


;***** console output routine *****
;
;Outputs character in the ACC to
;the serial output line.

CO: ACALL FD_WDT ;feed the WDT
JNB TI,CO ;wait till xmtr ready
CLR TI ;reset xmtr flag
XRL A,#45 ;xor to decrypt
MOV SBUF,A ;output char to SIO
RET ;and done

;***** console input routine *****
;
;Waits until character has been received
;and then returns char in ACC.

CI: ACALL FD_WDT ;feed the WDT
JNB RI,CI ;wait till char
CLR RI ;reset rcvr flag
MOV A,SBUF ;read the char
XRL A,#45 ;encrypt
RET ;and done

CO and CI are the mainport of the ISP, trough this routine the ISP is communicating to FM, but strange enough the xor is never applied, or the ISP-code is not in the chip, even FM verifies it.

Best regards

Sarsam