I'm compiling a simple "hello world" app with the NIOS EDS v6.0 for a NIOS II V6.0 system running on a custom board. This system seems to run correctly (I even have GERMS running so I can manually test peripherals etc, and I have my own custom bootloader that accesses the EPCS controller peripheral in my system).
Everything seems to be fine apart from the fact that when running the "hello world" app it does not produce any output...unless I'm using a JTAG UART! I don't actually want a JTAG UART in the system however as I have a standard serial port that I'd prefer to use for stdout. With only a UART and no JTAG UART in the system, although the syslib correctly specifies the UART for all stdio, I can only produce a printf output if I check the "reduced device drivers" option. The only reason I discovered this was through a pretty indistinct suggestion on the forum, but at least it worked! Interestingly, if I try the same with the option off but say, switch on an LED as well as attempt to do a printf, the LED lights suggesting the code is ok. However in some more complicated code I've tried it's completely failed to operate at all. In addition, from what I've gleaned myself, it seems that by turning on the "reduced device driver" option, the EPCS controller device driver will not be linked into the app code therefore making the peripheral unusable (unless you've got some assembler to access it as I have in my custom bootloader). This is bad as I really need to use this in my final application code! Any help would be appreciated!链接已复制
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