Ah, yes — that’s a **URL-encoding issue**. `%20` is the encoded representation of a space, so SpeedupAI is apparently interpreting the pasted text as a URL or encoded input.

Try this version **without the code block**. I’ll also remove formatting that can sometimes trigger the encoding problem.

Copy from **PROJECT:** through the end:

PROJECT: Production-grade solar smart-agriculture IoT proof of concept. Design THREE coordinated devices: 1) cattle smart eartag, 2) soil NPK/soil-health probe, 3) solar LoRaWAN gateway/edge processor. Generate an engineering-ready circuit architecture first, with enough detail to later produce verified schematics, BOM and PCB layouts. DO NOT treat the targets below as proven facts; validate them and flag conflicts.

CRITICAL RULE: MINIMIZE ASSUMPTIONS. Never invent MPNs, specifications, datasheets, lifecycle status, sensor accuracy, radio capacity or certification. Use current manufacturer datasheets/product pages for component selection. Give exact MPNs where verified; otherwise mark UNVERIFIED and explain what must be selected. Prefer active or recommended-for-new-design parts and provide alternatives for critical parts. Distinguish component capability from complete-system performance.

SYSTEM GOALS:
Eartag: HR target ±5 bpm, GNSS <5 m outdoors, >2-year life, 3–5 days without useful sun, IP67, thin/rounded, livestock-safe.
Soil probe: NPK target ±10%, moisture ±3%, EC ±0.1 mS/cm, >3-year life, IP67, modular/replaceable sensing head, 3–5+ days without useful sun.
Gateway: ≥10,000 registered devices. This MUST be supported by an actual traffic/capacity model. Target <100 ms local preprocessing, <5 W average under defined conditions, >5-year design life, ≥7 days autonomy, IP65, pole-mountable.
Initial BOM targets: eartag <$20, probe <$50, gateway <$200. Treat these as targets, not guaranteed.

EARTAG:
Architecture: dry electrodes → protected ECG AFE → low-power MCU → motion/artifact detection → LoRa → periodic GNSS → solar/energy harvesting + storage.
Investigate TI ADS1292R for ECG, ST IIS2DLPC-class accelerometer, current u-blox M10-series GNSS, SX1276-class LoRa and BQ25570-class energy harvesting. VERIFY every exact MPN and lifecycle before using it.
Challenge dry-electrode ECG. Cattle hair, anatomy, motion, dirt and contact pressure may make ±5 bpm unrealistic in all conditions. Design signal-quality and lead-off detection. Return HR + confidence + INVALID when unreliable. Validate against an independent reference using MAE, RMSE, bias and 95% confidence or agreement limits.

SOIL PROBE:
Architecture: stainless-steel or appropriate electrodes + ISE/electrochemical sensing + optical spectroscopy + capacitive moisture + temperature + EC → low-power MCU → sensor fusion/calibration → LoRa → solar/storage.
Investigate AD5940-class electrochemical AFE and verify the exact part. DO NOT assume optical spectroscopy directly measures NPK. Treat it as a model input.
Calibration must account for sand, loam, clay, organic and saline soils, moisture, temperature, ionic strength, electrode aging and drift. Store sensor ID, calibration coefficients, calibration date, revision and soil-class/model metadata.
Validate against laboratory reference samples. Report MAE, RMSE, R², bias, confidence and independent test performance. If ±10% cannot be demonstrated in field conditions, say so.

GATEWAY:
Architecture: LoRa concentrator such as SX1302/SX1303-class + compute such as RISC-V U74/K510 or current alternatives + LTE/Wi-Fi/Ethernet + solar MPPT + LiFePO4.
DO NOT call ordinary LoRaWAN a mesh network. Model the actual LoRaWAN architecture and capacity.
For 10,000 devices calculate reporting interval, payload, spreading-factor distribution, airtime, channel utilization, collisions, retries, downlinks, packet delivery ratio, backhaul and CPU/RAM load. If one gateway cannot meet the traffic target, calculate the required gateway count/density.
Do not assume RISC-V is automatically lower-power or better than ARM. Compare objectively.
Edge processing should include packet validation, deduplication, timestamps, confidence/error flags, local aggregation and sensor-quality preprocessing.

POWER AND SOLAR:
Create a power tree and energy budget for every subsystem: sleep, sensing, MCU, GNSS, LoRa TX/RX, optical/ISE sensing, regulators, storage leakage and backhaul.
Calculate Wh/day, peak current, usable battery energy, solar input and autonomy.
Include conversion efficiency, battery aging, temperature derating, solar degradation and cloudy-weather margin.
Never claim 3–7 day autonomy without calculations.
Flag conflicts such as <10 mW soil sensing versus spectroscopy, <5 W gateway versus LTE/edge compute, and thin eartag versus battery/solar area.

PCB AND HARDWARE:
Provide circuit-level architecture with separate or controlled analog, digital, RF and switching-power domains. Keep noisy/high-current paths away from ECG and electrochemistry. Use a continuous ground strategy. Provide 50-ohm RF routing, antenna keep-outs, matching network and RF test access. Provide ESD, surge and reverse-polarity protection on external interfaces. Provide gateway thermal management, programming/debug interfaces, production test points, modular soil sensor connectors and a realistic 4-layer or greater stack-up where required. Include DFM/DFA, enclosure/IP interfaces and serviceability.
Do not claim IP65 or IP67 from PCB design alone; enclosure sealing must be engineered and tested.

SAFETY AND COMPLIANCE:
Consider applicable regional LoRa frequency/RF rules, EMC/ESD, RoHS/REACH, battery safety including IEC 62133-2 where applicable, environmental qualification and livestock welfare.
No sharp edges, unsafe exposed conductors or excessive surface heating.
Do not claim certification without testing.

REQUIRED OUTPUT:

1. System block diagram and interfaces.
2. Assumptions, unknowns and confidence level.
3. Exact verified component/MPN table with manufacturer, MPN, function, package, key limits, lifecycle, source and alternative.
4. Circuit architecture for all three devices including critical values, interfaces and protection.
5. Power tree, Wh/day and autonomy calculations.
6. RF architecture and quantitative 10,000-device capacity model.
7. Sensor calibration and data-quality strategy.
8. PCB placement, routing and stack-up guidance.
9. Preliminary BOM and cost at prototype, 1k, 10k and 100k where meaningful.
10. Validation plan with measurable acceptance criteria for sensor MAE/RMSE, ECG HR error, GNSS accuracy, packet delivery, latency, power, thermal and environmental tests.
11. Risk register with probability, impact, mitigation and validation.
12. Requirement traceability matrix.
13. Clearly label every TARGET CONFLICT or UNVERIFIED claim.

ENGINEERING RULE:
Do not optimize for making every original target appear achievable. Optimize for a defensible design. If requirements conflict, quantify the conflict and propose the minimum necessary change.
Separate LAB performance, controlled field performance and expected real-world performance.
Do not silently substitute components, architectures or assumptions.

IMPORTANT: Produce a circuit architecture suitable for later schematic and PCB generation. Do not prematurely generate a PCB based on unverified assumptions. Flag anything that requires engineering validation before schematic lock.

**If SpeedupAI still converts spaces to `%20`, tell me what appears in the field after you paste it (or send me a screenshot), because that would indicate the website is processing the input as encoded text rather than ordinary text.**