hello dear Mikrocontroller.net users, i am a dutch student in electronics and currently working my practical year/exams, my assignment is to make a controller for a Digital Sound Processor, for amplifier racks in Professional Audio. in such a rack there are four DSP's who'm constantly need to be checked if current setting is the right one therefor i needed to create a network of multiple uC's the network of uC's is simply controlled with 5 buttons and a LCD. now come's the tricky bit(for me that is), also custom settings should be loaded to the DSP's this happens through the master uC's UART on to SPI to selected Slave in LCD menu, the slave then sends it using its uart to the DSP.. and this won't work. i have tested the UART it self and the SPI and both (seem to) work, i have pulled out my signalscoop and measured all variables but my output signal just isn't there. i simply used the examplary codes from Datasheets for testing purposes but this didn't work either. how ever it clearly works seperatly.. the network master is an ATmega8515 the 4 slaves are ATmega8's there is also an SPI EEprom chip to store all the presets to. my programming language is Assembly. if any of you have some working code and/or scheme's i would be helped a lot.