I am using the USRP and TV_RX in slot B to capture over the air signals.
understand the receive chain processing inside of the FPGA and was
get the complex 16-bit I and Q samples out at the debug IO pins. As a
run I tried connecting 12-bit the rx_a_b input to the debug IO pins and
could do so successfully by enabling appropriate registers and modifying
usrp_std.v. However, in the usrp_std.v I am unable to pinpoint the
that carry I and Q channels that come out of the receive chain. I tried
routing the bb_rx_i0 and bb_rx_q0 signals that come out of the
block. Since I am running 1rx and 1tx configuration only rx_chain_0 is
enabled, I guess. However I do not see any outputs when I connect these
signals to the debug pins using debug_0(bb_rx_q0),.debug_1(bb_rx_i0). I
a Basic RX and Basic TX in A slots to look at the outputs. I also tried
routing the signals labeled ch0rx, ch1rx to debug pins but still no
Then in my desperation I tried routing the rest of ch2rx to ch7rx to
pins with a new rbf file everytime but still no outputs. I could verify
the ddc0_in_i signals are toggling but the bb_rx_i0 and bb_rx_q0 do not
to toggle. I would like to look at individual I Q signals and then
eventually connect the interleaved I and Q that go to the USB.
Any help/guidelines appreciated.
assign ch0rx = counter ? debug_counter : loopback ? loopback_i_0 :
assign ch1rx = counter ? debug_counter + 16’d1 : loopback ?
assign ch2rx = bb_rx_i1;
assign ch3rx = bb_rx_q1;
assign ch4rx = bb_rx_i2;
assign ch5rx = bb_rx_q2;
assign ch6rx = bb_rx_i3;
assign ch7rx = bb_rx_q3;
wire [31:0] rssi_0,rssi_1,rssi_2,rssi_3;
.ddc0_in_i(ddc0_in_i),.ddc0_in_q(ddc0_in_q), .ddc1_in_i(ddc1_in_i),.ddc1_in_q(ddc1_in_q), .ddc2_in_i(ddc2_in_i),.ddc2_in_q(ddc2_in_q),