Lab 11.7 - PS-side AXI-Lite BPSK bring-up

Lab 11.7 - PS-side AXI-Lite BPSK bring-up

Goal

Execute the smallest reproducible Processing System control sequence for the deterministic BPSK burst core:

PS / software -> AXI-Lite registers -> framed BPSK BER core -> AD9363 discovery burst

This lab bridges:

• Lab 5.11, which defined and verified the AXI-Lite register contract;
• Lab 6.3, which fixed the AD9363 gain and frequency discipline for the first RF run;
• Block 11 hardware handoff, where one short burst must be launched safely and reproducibly.

Engineering question

What is the minimum PS-side sequence that should succeed before longer RF measurements or BER campaigns are attempted?

Executable file

File	Purpose
blocks/block_11_integrated_sdr_project/python/lab_11_7_axi_lite_bpsk_bringup.py	reads AXI-Lite ID, programs burst registers, launches one run, polls busy/done, reads BER counters

Local mock run

Run from the repository root:

python blocks/block_11_integrated_sdr_project/python/lab_11_7_axi_lite_bpsk_bringup.py \
  --backend mock \
  --max-total-errors 0 \
  --max-payload-errors 0 \
  --json-out docs/assets/lab117_axi_lite_bringup_mock.json

Expected local behavior:

• the script exits with code 0;
• busy_observed and done_observed are both true;
• received_bits == frame_bit_count;
• total_errors == 0;
• payload_errors == 0.

Real board run

On the Zynq Linux image, run as root or through sudo. Use the actual AXI-Lite base address from Vivado Address Editor, exported headers, or board handoff notes.

You can inspect an exported Vivado handoff file directly from this repository:

python tools/inspect_xsa_memmap.py hardware/7020_ad936x_sdr/ps/ad936x_no_os_reference/system_top.xsa
python tools/inspect_xsa_memmap.py path/to/your_regenerated_design.xsa --find bpsk --require-match

The helper also understands vendor ZIP bundles that contain a nested system_top.xsa, for example:

python tools/inspect_xsa_memmap.py E:\7020\7020_AD936X_SDR\Vivado2021.1\Driver_PL_PS\AD936X_PS.zip --find axi_ad9361

The current ad936x_no_os_reference/system_top.xsa export contains axi_ad9361 and the two DMA windows, but it does not yet contain bpsk_zynq_ber_axi_lite. Until the custom modem IP is inserted into the block design and the XSA is regenerated, any --base-addr value below is only a placeholder example.

Vendor package note from E:\7020:

• the firmware bundle is Pluto-like and uses root / analog;
• the serial console guidance is 115200 baud;
• the bundled uEnv.txt sets ipaddr=192.168.2.1 and ipaddr_host=192.168.2.10;
• companion README files in the same bundle also mention 192.168.1.10.

That mismatch is exactly why the course flow should probe the active image first instead of assuming the vendor default IP.

Direct /dev/mem mapping:

sudo python blocks/block_11_integrated_sdr_project/python/lab_11_7_axi_lite_bpsk_bringup.py \
  --backend mmap \
  --base-addr 0x43C00000 \
  --frame-bit-count 281 \
  --preamble-count 25 \
  --start-offset 62 \
  --json-out reports/lab117_axi_lite_bringup.json

Fallback through the devmem utility:

sudo python blocks/block_11_integrated_sdr_project/python/lab_11_7_axi_lite_bpsk_bringup.py \
  --backend devmem \
  --base-addr 0x43C00000 \
  --frame-bit-count 281 \
  --preamble-count 25 \
  --start-offset 62 \
  --json-out reports/lab117_axi_lite_bringup.json

Host-side remote check over Ethernet, without copying the script to the board:

python blocks/block_11_integrated_sdr_project/python/lab_11_7_axi_lite_bpsk_bringup.py \
  --backend ssh-devmem \
  --ssh-host 192.168.40.1 \
  --ssh-user root \
  --ssh-password analog \
  --base-addr 0x43C00000 \
  --frame-bit-count 281 \
  --preamble-count 25 \
  --start-offset 62

Live board note on 2026-06-19:

• the stock course-clean image answered over IIO at 192.168.40.1;
• the live device tree declared mwipcore@43c00000 with compatible = "mathworks,mwipcore-axi4lite-v1.00";
• direct register reads to 0x43C00000 + {0x00..0x1C} returned Bus error, while ADI reference windows at 0x79020000, 0x79024000, 0x7C400000, and 0x7C420000 were readable.

That means the current board image is not ready for Lab 11.7 bring-up yet: the address is declared, but the loaded PL design does not expose a working slave at that window.

Backends

Backend	Intended use
mock	local CI-friendly self-check without hardware
mmap	direct Linux /dev/mem access on the board
devmem	fallback when /dev/mem mapping is inconvenient but devmem exists
ssh-devmem	host-side remote devmem access over SSH to a live Linux board

Register contract

This lab uses the same map as Lab 5.11:

Offset	Name	Meaning
0x00	CONTROL_STATUS	write bit 0 to start, read bit 1 for busy, read/write bit 2 for sticky done
0x04	FRAME_BIT_COUNT	total transmitted and compared bits
0x08	PREAMBLE_COUNT	preamble bits excluded from payload BER
0x0C	START_OFFSET	deterministic sample index for decisions
0x10	RECEIVED_BITS	recovered bits after the burst
0x14	TOTAL_ERRORS	all bit errors
0x18	PAYLOAD_ERRORS	payload-only bit errors
0x1C	ID	expected identification word 0x4250534B

First discovery-burst order

1. Probe the AD9363 context with Lab 6.3 or iio_attr.
2. Keep TX power at minimum and RX gain low/manual.
3. Disable AGC for the first burst.
4. Read ID first through AXI-Lite.
5. Program FRAME_BIT_COUNT, PREAMBLE_COUNT, and START_OFFSET.
6. Launch one short burst.
7. Poll busy and done.
8. Read BER counters and clear sticky done.

Generated artifact

The mock run writes:

docs/assets/lab117_axi_lite_bringup_mock.json

The JSON report captures the programmed configuration, observed status bits, BER counters, and a final register snapshot.

Report checklist

• [ ] Record the actual AXI-Lite base address used on hardware.
• [ ] Show one successful ID readback.
• [ ] Show programmed FRAME_BIT_COUNT, PREAMBLE_COUNT, and START_OFFSET.
• [ ] State whether busy and done were both observed.
• [ ] Record RECEIVED_BITS, TOTAL_ERRORS, and PAYLOAD_ERRORS.
• [ ] State whether the first run is discovery-only or already BER-grade.
• [ ] Link the run to the AD9363 settings table from Lab 6.3.

Engineering conclusion template

The PS-side AXI-Lite bring-up path is ready / not ready.
The core ID readback is ______, the burst status sequence is ______, and the BER counters are ______.
The next step is ______.