Problem setting up Red Pitaya with old ecosystem

[chrispwkoe]

Hello Nils, Hi everyone,

Recently I have downgraded the ecosystem of my redpitaya to version 0.93.
I have done this, because I wanted to use the axi_adc program
and as far as I understood, it is incompatible with newer versions of the ecosystem.

However, I have some serious trouble when I attempt to run simple C programs,
like the digital_led_blink example.
I have compiled them on a host system and send them to my RP via scp.
I try to run it, typing

redpitaya> LD_LIBRARY_PATH=/lib ./digital_led_blink

but I keep getting errors like:

-sh: ./digital_led_blink: not found

I tried entering other paths for the library, but still the same error.

I thought, maybe I did something wrong when I compiled. So I attempted to download the repository to the
RP and building it on the board but it doesnt work at all and I get similar errors:

redpitaya> git clone some_stuff
-sh: git: not found
redpitaya> sudo apt-get install git
-sh: sudo: not found


I have no idea what these errors are supposed to mean
and it is almost impossible to google this, because the terms are very general.

I'm terribly sorry, if this is actually a really dumb problem, but I'm not that experienced
with linux.
Can someone help me with this issue? Thank You!

Kind Regards
Christian

[Nils Roos]

Hi,
the problem is that between 0.93 and 0.94 the target architecture for compilation of everything was changed from soft-float to hard-float. Binaries are incompatible between the different architectures unless the system has multi-arch support - and the Red Pitaya OS does not. Trying to execute an incompatible binary leads to the somewhat misleading error message you got.
In 0.93 compilation on the target was not yet possible and neither was adding packages, with apt-get or otherwise. To build for 0.93 you'd need to get the linaro toolchain as described in the README.md from that version.

But all this is moot because you can compile and run the axi_adc code under 0.96 just fine. The only thing you need to do is to load the right fpga bitstream before running your program. The 0.93 bitstream from the release is not the right one, by the way, this one is. There's a bug with transferring data in the official one.

[chrispwkoe]

Hi again,

and thanks for the fast reply.
I have tried the modified bitstream today and it seems to work perfectly.

Nice work!

Just out of curiousity: does this mean, that old code (compiled for 0.92 or 0.93) will still run on the new ecosystem?
And, btw, what is the deal with the "Bicycle Repair Man"-signature?

Thank You very much!

kind Regards
Christian

[Nils Roos]

Just out of curiousity: does this mean, that old code (compiled for 0.92 or 0.93) will still run on the new ecosystem?

The compiled executables from old versions can't be used on the newer ones, but if you compile the sourcecode again in the new system, it will at least start. If the code relies on specific fpga features, it may be neccessary to load the appropriate bitstream first in order to make it function correctly.

what is the deal with the "Bicycle Repair Man"-signature?

That's one of my favorite quotes from Monty Python's Flying Circus. Look it up on youtube if you never heard of it^^