rf_port_select does not work

On the Pluto, only the A Balanced inputs are used.

Therefore the other settings are locked - please see here:

https://github.com/analogdevicesinc/linux/blob/master/arch/arm/boot/dts/zynq-pluto-sdr.dtsi#L248

You should be able to control the RX/TX LOs using altvoltage0 or altvoltage1.

When you iio_device_find_channel() you need to make sure that you look for an output channel...

-Michael

Hi mhennerich 

Thank You for the assistance. I will follow the indication.
I have further questions.
I want to reread the attribute.
A list of what happens:
1. iio_channel_attr_read( phy_chn_tx, "rf_port_select", (char*)txcfg.rfport, 10 )  -> -10014
2. iio_channel_attr_read_longlong( phy_chn_tx, "rf_bandwidth", &txcfg.bw_hz ); -> -22
3. iio_channel_attr_read_longlong( phy_chn_tx, "sampling_frequency", &txcfg.fs_hz ); -> 0
4. iio_channel_attr_read_double(   phy_chn_tx, "hardwaregain", &txcfg.gain_db ); -> 0 but gain = 2600000
5. iio_channel_attr_read_longlong( phy_chn_tx, "frequency", &txcfg.lo_hz); -> -2
6. iio_channel_attr_read(          phy_chn_rx, "rf_port_select", (char*)rxcfg.rfport, 10 ); -> -5
7. iio_channel_attr_read_longlong( phy_chn_rx, "rf_bandwidth", &rxcfg.bw_hz ); -> -10053
8. iio_channel_attr_read_longlong( phy_chn_rx, "sampling_frequency", &rxcfg.fs_hz ); -> -10053
9. iio_channel_attr_read_double(   phy_chn_rx, "hardwaregain", &rxcfg.gain_db ); -> -10053
10. iio_channel_attr_read_longlong( phy_chn_rx, "frequency", &rxcfg.lo_hz); -> -2

The attributes were written previously with return code 0.
I suppose I should reread the same values. What happens?
Where are the return codes ?
Thank You

Pietro

Can you provide a simple example in just C?

-Travis

Hi Travis

The initialization appears correct ..
The readout is totally out of order.

printf("* Initializing streaming channels\n");
tx0_i = iio_device_find_channel(tx, "voltage0", true);
if (!tx0_i)
tx0_i = iio_device_find_channel(tx, "altvoltage0", true);

tx0_q = iio_device_find_channel(tx, "voltage1", true);
if (!tx0_q)
tx0_q = iio_device_find_channel(tx, "altvoltage1", true);

// Up to here it is correct

// Now I want to read and nothing works

struct stream_cfg txcfg_read;

{
txcfg_read.rfport = " ";
txcfg_read.bw_hz = 0;
txcfg_read.fs_hz = 0;
txcfg_read.gain_db = 0;
sz = iio_channel_attr_read(tx0_i, "rf_port_select", (char*)txcfg_read.rfport, 10);
int err2 = iio_channel_attr_read_longlong(tx0_i, "rf_bandwidth", &txcfg_read.bw_hz);
err2 = iio_channel_attr_read_longlong(tx0_i, "sampling_frequency", &txcfg_read.fs_hz);
err2 = iio_channel_attr_read_double(tx0_i, "hardwaregain", &txcfg_read.gain_db);
}

Thank     You

Pietro

It looks like you reading channels from the wrong device.

For Pluto there are 3 relevant IIO devices...

Can you start with the iio_info command?

Is this the outcome?

This example is working for streaming it does the initialization without any problem. I just add the lines of code for reading what is already written. 

Can You modify the example for streaming and show this  API work?

Thank You

Pietro

So Michael was referring to the IIO devices that you reference for pulling back information. You can use iio_info and iio_attr to examine what is available. First I would start with iio_attr to list the devices as so:

iio_attr -u ip:pluto.local -d
IIO context has 5 devices:
	iio:device0, adm1177: found 0 device attributes
	iio:device1, ad9361-phy: found 18 device attributes
	iio:device2, xadc: found 1 device attributes
	iio:device3, cf-ad9361-dds-core-lpc: found 0 device attributes
	iio:device4, cf-ad9361-lpc: found 0 device attributes

The devices cf-ad9361-dds-core-lpc and cf-ad9361-lpc are the controls for data streaming and DDS control. You can tell since they have scan elements (that's an IIO concept for buffer management):

iio_attr -u ip:pluto.local -s -c cf-ad9361-lpc
dev 'cf-ad9361-lpc', channel 'voltage0' (input, index: 0, format: le:S12/16>>0)
found 6 channel-specific attributes
dev 'cf-ad9361-lpc', channel 'voltage1' (input, index: 1, format: le:S12/16>>0)
found 6 channel-specific attributes

iio_attr -u ip:pluto.local -s -c cf-ad9361-dds-core-lpc
dev 'cf-ad9361-dds-core-lpc', channel 'voltage0' (output, index: 0, format: le:S16/16>>0)
found 4 channel-specific attributes
dev 'cf-ad9361-dds-core-lpc', channel 'voltage1' (output, index: 1, format: le:S16/16>>0)
found 4 channel-specific attributes

The ad9361-phy is where all the main control attributes for the transceiver live:

iio_attr -u ip:pluto.local -c ad9361-phy .
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'external', value '0'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'fastlock_load', value '0'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'fastlock_recall', ERROR: Invalid argument (22)
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'fastlock_save', value '0 183,183,183,183,183,183,183,183,183,183,183,183,183,183,183,183'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'fastlock_store', value '0'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'frequency', value '2450000000'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'frequency_available', value '[325000000 1 3800000000]'
dev 'ad9361-phy', channel 'altvoltage1' (output), id 'TX_LO', attr 'powerdown', value '0'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'bb_dc_offset_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'filter_fir_en', value '0'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'gain_control_mode', value 'slow_attack'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'gain_control_mode_available', value 'manual fast_attack slow_attack hybrid'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'hardwaregain', value '71.000000 dB'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'hardwaregain_available', value '[-3 1 71]'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'quadrature_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rf_bandwidth', value '18000000'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rf_bandwidth_available', value '[200000 1 56000000]'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rf_dc_offset_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rf_port_select', value 'A_BALANCED'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rf_port_select_available', value 'A_BALANCED B_BALANCED C_BALANCED A_N A_P B_N B_P C_N C_P TX_MONITOR1 TX_MONITOR2 TX_MONITOR1_2'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'rssi', value '114.25 dB'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'sampling_frequency', value '30720000'
dev 'ad9361-phy', channel 'voltage0' (input), attr 'sampling_frequency_available', value '[2083333 1 61440000]'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'filter_fir_en', value '0'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'raw', value '306'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'rf_bandwidth', value '18000000'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'rf_bandwidth_available', value '[200000 1 40000000]'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'rf_port_select_available', value 'A B'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'sampling_frequency', value '30720000'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'sampling_frequency_available', value '[2083333 1 61440000]'
dev 'ad9361-phy', channel 'voltage3' (output), attr 'scale', value '1.000000'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'external', value '0'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'fastlock_load', value '0'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'fastlock_recall', ERROR: Invalid argument (22)
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'fastlock_save', value '0 230,230,230,230,230,230,230,230,230,230,230,230,230,230,230,230'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'fastlock_store', value '0'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'frequency', value '2400000000'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'frequency_available', value '[325000000 1 3800000000]'
dev 'ad9361-phy', channel 'altvoltage0' (output), id 'RX_LO', attr 'powerdown', value '0'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'filter_fir_en', value '0'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'raw', value '306'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'rf_bandwidth', value '18000000'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'rf_bandwidth_available', value '[200000 1 40000000]'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'rf_port_select_available', value 'A B'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'sampling_frequency', value '30720000'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'sampling_frequency_available', value '[2083333 1 61440000]'
dev 'ad9361-phy', channel 'voltage2' (output), attr 'scale', value '1.000000'
dev 'ad9361-phy', channel 'temp0' (input), attr 'input', value '30702'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'filter_fir_en', value '0'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'hardwaregain', value '-10.000000 dB'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'hardwaregain_available', value '[-89.750000 0.250000 0.000000]'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'rf_bandwidth', value '18000000'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'rf_bandwidth_available', value '[200000 1 40000000]'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'rf_port_select', value 'A'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'rf_port_select_available', value 'A B'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'rssi', value '0.00 dB'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'sampling_frequency', value '30720000'
dev 'ad9361-phy', channel 'voltage0' (output), attr 'sampling_frequency_available', value '[2083333 1 61440000]'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'bb_dc_offset_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'filter_fir_en', value '0'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'gain_control_mode_available', value 'manual fast_attack slow_attack hybrid'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'offset', value '57'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'quadrature_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'raw', value '1255'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'rf_bandwidth', value '18000000'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'rf_bandwidth_available', value '[200000 1 56000000]'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'rf_dc_offset_tracking_en', value '1'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'rf_port_select_available', value 'A_BALANCED B_BALANCED C_BALANCED A_N A_P B_N B_P C_N C_P TX_MONITOR1 TX_MONITOR2 TX_MONITOR1_2'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'sampling_frequency', value '30720000'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'sampling_frequency_available', value '[2083333 1 61440000]'
dev 'ad9361-phy', channel 'voltage2' (input), attr 'scale', value '0.305250'
dev 'ad9361-phy', channel 'out' (input), attr 'voltage_filter_fir_en', value '0'

Since you don't specify in your code how "tx" is created, our guess is that its not from ad9361-phy.

-Travis

Hi Travis

I changed the call to the read this way

err2 = iio_channel_attr_read_bool( iio_device_find_channel(phydev, "voltage0", true), "rf_bandwidth", &pluto_ad9361_phy_attrib.voltage0_out.filter_fir_en ); // wrong
iio_strerror(err2, buf2, 200);
err2 = iio_channel_attr_read(iio_device_find_channel(phydev, "voltage0", true), "rf_port_select", pluto_ad9361_phy_attrib.voltage0_out.rf_port_select, 20 ); // wrong
iio_strerror(err2, buf2, 200);

Now all of the readings are working. But the difference is the channel is inlined every time rather than recycled from a variable. It should not make any difference but ... That's it.

Thank You

Pietro

Reusing a channel pointer or re-creating it does not matter.

-Travis

Thank You for this support. I am trying to learn  just doing.

I have a different behaviour or the command 

iio_attr -u ip:pluto.local -c ad9361-phy

I get 

dev 'ad9361-phy', channel 'altvoltage1', id 'TX_LO' (output), found 8 channel-specific attributes
dev 'ad9361-phy', channel 'voltage0' (input), found 15 channel-specific attributes
dev 'ad9361-phy', channel 'voltage3' (output), found 8 channel-specific attributes
dev 'ad9361-phy', channel 'altvoltage0', id 'RX_LO' (output), found 8 channel-specific attributes
dev 'ad9361-phy', channel 'voltage2' (output), found 8 channel-specific attributes
dev 'ad9361-phy', channel 'temp0' (input), found 1 channel-specific attributes
dev 'ad9361-phy', channel 'voltage0' (output), found 10 channel-specific attributes
dev 'ad9361-phy', channel 'voltage2' (input), found 13 channel-specific attributes
dev 'ad9361-phy', channel 'out' (input), found 1 channel-specific attributes

I do not access the attributes of the channels. How to get the same result You have?

Thank  You'

Pietro

I am trying to get the channel attributes but I do not get.
Is there a different version?

Thank You

Pietro

You are missing the dot "." at the end of the command. Needs to be:

iio_attr -u ip:pluto.local -c ad9361-phy .

-Travis

You are missing the dot "." at the end of the command. Needs to be:

iio_attr -u ip:pluto.local -c ad9361-phy .

-Travis

Yes.. 

That's it

Thank You