On 05/31/2021 09:07 AM, Alexey Silyuk wrote:
Thanks for the answer, so what is the order of pushing samples to the
mock buffer? if i want to ensure that i am receiving correct data i
pushed after calling recv() using float or double type?
The ordering on the "wire" is IQIQIQIQ, and similarly on the
converted-to-host-format side.
пн, 31 мая 2021 г. в 15:44, Marcus D. Leech <[email protected]
<mailto:[email protected]>>:
On 05/31/2021 08:30 AM, Alexey Silyuk wrote:
> HI everybody, I am new at mailing list.
> These days I am writing an emulator for emulating tx/rx streams
based
> on uhd 3.15LTS
> I am using device usrp2 device from uhd/lib.
> As I saw in examples (rx_samples_to_file), I am creating a mock
> streamer ( taken from uhd tests ).
> and now i want to push samples inside the buffer.
> I see that i can define type of samples, if am using 'short'
type of
> samples, I am creating uint32_t variable, 16 MSB i put real part of
> sample, and 16 LSB i put imaginary part of sample (i am using
little
> endian)
> After that i am calling usrp->recv() and i get samples as i
defined (
> spp is 2000)
> (0,0)
> (2,2)
> ....
> (1999,1999)
> as expected, according to data I push to the mock buffer.
>
> now while i want to use type 'float' i am using for example
> float real = 1.5
> float imag = 2.5
> and trying to push sample to the mock buffer, i am doing:
> buffer[0] = (uint32_t)real;
> buffer[1] = (uint32_t)imag;
>
> and expecting to get after calling usrp->recv()
> (1.5, 2.5)
> but i get incorrect result (convertor settings: cpu_format "fc32",
> otw_format "sf16" )
>
> i am printing real and imag parameters as bitset<32> and see in
real
> part, in 16 LSB part of result, my 16 MSB bits from sample value
1.5,
> and in imagine part zeros, in next sample i see in 16 LSB part of
> result, 16 MSB bits of sample value 2.5. I mean one sample i
push to
> buffer uses whole sample after calling recv()
>
> P.S i set scale factor to 1.0
>
> What am I doing wrong to use the type 'float' and 'double' for mock
> samples?
> I am new at usrp so I don't understand what samples I should
use, will
> be glad to get references.
> Thanks
>
>
Your OTW format is still SC16 -- normally only the *HOST* side uses
floating-point and no actual USRP devices that I'm aware of can
support floating-point *ON THE WIRE* (OTW).
_______________________________________________
USRP-users mailing list -- [email protected]
<mailto:[email protected]>
To unsubscribe send an email to [email protected]
<mailto:[email protected]>
_______________________________________________
USRP-users mailing list -- [email protected]
To unsubscribe send an email to [email protected]
_______________________________________________
USRP-users mailing list -- [email protected]
To unsubscribe send an email to [email protected]
