Microcontrollore Jobs

Project: USB HID Passthrough Firmware for Feather RP2040 with USB Host I am looking for an embedded developer experienced with USB firmware and the RP2040 platform. Hardware: Feather RP2040 with USB Host support Requirements: Develop or modify firmware so the board acts as a USB host for HID devices. Implement USB HID passthrough so connected devices (such as mice, keyboards, or other HID devices) are forwarded to the connected computer. Support at least 5 HID interfaces simultaneously. The USB serial number (iSerialNumber) must not be passed through from the connected device or changed. The firmware should work with generic HID devices without requiring device-specific drivers. Expected Result: Stable firmware running on the Feather RP2040. Reliable passthrough for multiple HID devices...

I need a plug-and-play USB dongle that quietly presents itself to the laptop as a standard HID mouse and then, without any host software, begins moving the pointer in truly random, human-like paths. Every travel should land on random points across the screen, never following a predictable grid or loop, and the velocity needs to ebb and flow so it looks as if an actual hand is guiding it rather than a script—variable speeds are essential. Because I will sometimes want to pause the motion or cycle through a couple of intensity presets, all adjustment must live on the device itself: a small tactile button (or a pair, if easier) that toggles the mover on/off and steps through, say, slow, medium, or fast randomness. No companion app, driver, or registry edits—just pure hardware con...

I need an experienced Beckhoff TwinCAT engineer who can take full ownership of PLC programming, HMI development, and overall system integration for a medium-scale manufacturing line now entering its pre-production phase. The hardware is already in place (CX and EtherCAT I/O), so the focus is on creating clean, modular TwinCAT 3 code, building a responsive HMI that operators can learn in minutes, and tying everything together with reliable communication to our existing MES. Scope • Develop and document TwinCAT 3 PLC logic for motion, safety, and process control. • Design the HMI (TwinCAT HMI or your preferred Beckhoff-compatible platform) with alarm handling, recipe management, and diagnostics. • Integrate third-party devices over EtherCAT and Modbus TCP, verifying det...

Project Title: KNX Programmer & UniFi Network Specialist for Luxury Smart Home (Remote Commissioning) Project Overview: I am completing a high-end period home renovation (15 zones) in Dublin, Ireland. The property features a fully centralized KNX smart home architecture. I have a registered, professional electrical contractor handling 100% of the physical installation, including cable pulling, containment, 21U rack building, hardware mounting, and electrical safety testing. I am looking for an experienced KNX Integrator to handle the software programming, logic creation, and remote commissioning via ETS6, as well as the configuration of our Ubiquiti UniFi network. The Hardware Stack: All hardware is already specified and ordered. The system consists of: The Brain: MDT KNX Power Su...

I am expanding the C language so it speaks directly to microcontrollers, specifically the ARM family on the ARM-v8 architecture. The goal is a clean, lightweight extension that lets developers toggle ports, poll sensors, drive LEDs or motors, and handle real-time tasks simply by touching the right memory-mapped registers. The finished tool-chain must compile down to code that runs fast, in tiny footprints, with deterministic timing. Think of the kinds of binaries you would drop into washing machines, automotive modules, or medical devices—only here the target is any ARM-based microcontroller. You will provide: • A documented language spec describing new keywords, pragmas, or intrinsics that expose registers, GPIO, interrupt vectors, and timing primitives. • A working ...

I am working on a compact RF application based on Silicon Labs’ SI4010 transmitter and now need a fresh set of expert eyes to get it production-ready. The hardware is already roughed-in and the core firmware skeleton is compiling, but performance still falls short of our targets in range, spectral cleanliness, and power efficiency. Your task spans three focused areas: • Schematic & PCB audit – flag layout, matching-network, or decoupling choices that could be detuning the front end. • Firmware tuning – refine register settings, timing, and wake-sleep sequencing in the SI4010 API so we hit our duty-cycle and current-draw goals without sacrificing link reliability. • Validation – document improvements with spectrum-analyzer plots, RSSI ver...

I’m building a suite of custom applications around the ESP32 and its BLE capabilities and need a skilled developer who can stay with me over the long haul on a part-time, as-needed basis. The work is a mix of firmware coding and light hardware design, so you should feel equally at home flashing code with ESP-IDF/Arduino C++ and laying out simple PCBs or reviewing schematics. Core task The boards will gather data from several sensors and peripheral modules, then broadcast or exchange that data over BLE with my mobile apps and back-end services. So far, the project roadmap includes: • Temperature sensors • Motion sensors • Humidity sensors • GPS, LoRa and RFID modules Your role – Extend and optimise the ESP32 BLE firmware to handle the data flow fro...

# Design two PCB Boards in EasyEDA for later JLCPCB manufacturing, including assembly. I am open to professional recommendations regarding peripheral components (sensors, power converters, connectors) and layout optimizations. However, the MCU selection for both boards is fixed as specified below. For Board 2, I prefer the CH32V003 but am open to other CH32 variants if there is a strong technical reason. ## Board 1: ESP32-H2 based BLE monitoring device prototype. - MCU: ESP32-H2-MINI-1-N4 (Internal 4MB Flash). - Sensors: LIS3DHTR (Accelerometer), GXHTC3 (Temp/Hum), MSM261DHT006 (I2S Mic Top Port). - Constraints: - Height: Max 5.0 mm (including components and PCB - Battery holder should be as low as reasonable like Keystone 3003). - Width: Max 25 mm. - Length: Any. - PCB ...

I already have a fully routed EasyEDA project built around an ESP32 running MicroPython. The first prototypes work, but the rest of the circuitry is over-engineered. I now want a fresh set of eyes to review and streamline every component except the ESP32 itself. The targets are clear: trim the bill of materials for lower cost, cut idle and peak current for better power efficiency, and, wherever possible, boost overall performance while reducing wiring complexity. That means analyzing every resistor, capacitor, connector, regulator, sensor and support IC on the board, justifying each part’s value, and proposing smarter substitutes or eliminations. After the review, I’ll need an updated schematic, a clean BOM, and a revised PCB layout ready for manufacturing export (Gerber, Pic...

I want a piece of wearable technology that creates a protective bubble just around my body, blocking or seriously attenuating incoming RF signals while also giving me the option to see what is trying to get through. In other words, it should both shield my own bio-signature from external probing and help me detect any active transmissions aimed at my immediate vicinity. The environment is highly personal—think a one-meter radius wherever I move—so the solution needs to travel with me rather than sit on a desk or in a wall. Comfort, size, and battery life therefore matter almost as much as raw shielding performance. What I imagine is a compact, self-contained module (belt clip, pendant, or similar form factor) that combines three core functions: 1. Real-time RF spectrum ...

I need a seasoned embedded engineer to design and implement a lean Time-Division Multiplexing protocol that funnels several high-speed ADC channels into a single, reliable UART stream. The end goal is clear: squeeze the maximum possible throughput out of the link without sacrificing data integrity. The work revolves around three core competencies—TDM protocol development, raw ADC data handling, and low-level UART communication—so fluency in each of these areas is essential. Our front-end hardware already produces digitised samples via a bespoke analog-to-digital conversion stage; your task is to move those samples efficiently over UART, interleaving them with tight framing, minimal overhead, and built-in error checking. Key deliverables • Well-documented C/C++ (or equi...

I’m building a custom handheld that plays original Game Boy Advance and Game Boy Color cartridges and I need the entire internal hardware engineered for it. I will be designing and manufacturing the outer shell myself, so your focus will be everything that sits inside the case: • A reliable GBA/GBC cartridge reader is the top priority; it must boot retail carts flawlessly. • Back-lit LCD (or IPS) screen driven at the correct refresh rate with minimal tearing. • Stereo speakers plus a small on-board amplifier and 3.5 mm headphone jack. • Rechargeable battery pack with USB-C charging and power-management circuitry (fuel gauge, protection, and safe-charge IC). • Responsive D-pad, A/B + L/R buttons, Start/Select, and volume control interface routed to a ...

PCB Design Brief Timeline Media Dock Controller Board This project requires a KiCad PCB design for the first prototype of a open source Media Dock. The dock is a hardware reader device used to interact with physical Media Volumes, which are media cartridges containing either storage media (SD card) or NFC identification tags. The board will be installed inside a dock enclosure and connected to a front display. Core Features The PCB must include support for the following components: Microcontroller ESP32 module (recommended) or equivalent microcontroller suitable for handling: SD card access NFC communication display control system logic NFC Reader The board must include an NFC reader chip (such as PN532 or equivalent) used to detect and read NFC tags embedded in Timeline medi...

This project is about building a physical “AI Secretary” system that combines a premium desk device with ultra‑simple wireless buttons people can stick anywhere to reach the same assistant. The goal is not just a gadget, but a coherent hardware family that makes interacting with my AI models feel tangible, fast, and effortless. At the center is the Desk Hub, a compact, high‑end box that lives on a desk like a small instrument. It has a small front display, a few physical buttons, a subtle light ring or LED bar, a microphone, and a speaker. Internally it runs on an ESP32‑class microcontroller with Wi‑Fi and Bluetooth. The Hub is always powered via USB‑C and always connected to my cloud backend, where all speech‑to‑text, language model processing, tools, and text‑to‑speech live. ...

I need an experienced FPGA programmer to assist with a data processing application. Key Requirements: - Proficiency in at least one of the following FPGAs: Xilinx, Altera, Lattice - Expertise in data processing applications - Familiarity with VHDL, Verilog, or SystemVerilog Ideal Skills and Experience: - Proven track record in FPGA programming - Strong background in data processing algorithms - Ability to work with various FPGAs and HDLs Please provide relevant experience in your bids. We need to develop ethernet hub in fiber optic 2 ports , and 16 SPI for chip led controller using data and clock . SPecia Ethernet protocol defined by us.

1: Simple Arduino device detecting a switch from a device 2: 2 RBG light strips with 16 LEDS 3: 4 input outputs for on and off

I am looking for an engineer or a small engineering team to help build a working prototype of a wearable smart ring that communicates with a thin wallet card device placed in a wallet. The purpose of the device is to prevent wallet loss by alerting the user when the wallet moves more than a short distance away from the ring. The system should provide two types of alerts: a vibration alert in the ring and an optional audio alert. The project goal is to create a fully working prototype that demonstrates the concept in real life. Experience with miniature electronics, wearable devices, Bluetooth communication, and prototype development is preferred.

I’m building a small arcade-style attraction made up of six identical stations. Each station will recognise when its hand-held controller is lifted by means of a magnetic sensor—or any other proper kind of sensor —then launch a three-minute countdown. Here is the user flow I need you to realise: 1. Controller is lifted → internal timer starts. 2. An OLED screen at that station immediately shows the remaining time, counting down in real time. 3. When the three minutes expire the screen simply replaces the countdown with a clear “Game Over, move to next zone ” message + a buzzer or light; 4. Once the controller is set back the system must reset itself, ready for the next player. Hardware thoughts so far: magnetic (reed or Hall) sensor to detect li...

I have a commercial IR-band Laser device with essentially two "Modes" - NORMAL and TRAINING, or restricted. Switching between the two can only be accomplished by accessing the Firmware via a proprietary 8-pin connection, for which I do not have a cable or interface. The candidate must either A) build a custom breakout to connect to the proprietary connector, or B) modify the OEM CONTROLLER pad and cable. Once the system is accessed, no custom coding, overwriting, or modification of the firmware will be required; the Candidiate need only identify the language, access the settings, and "flip the switch" between the two settings profiles. The hard part will be creating the connection. Something as simple as a POGO pin may be sufficient, but I am not qualified to say. T...

Hi everyone, I’m currently looking for a talented freelancer who has strong experience with Flowcode 10 and can create an amazing and efficient program for a project I’m working on. -Must be comfortable building programs in Flowcode 10 -Able to design clean, well-structured logic and functionality -Experience with microcontroller projects is a plus If you’re skilled with Flowcode and interested in collaborating, please comment below or send me a direct message with: • A short introduction • Your experience with Flowcode • Examples of previous work (if available) Looking forward to working with someone passionate about building great programs!

I need the internal circuitry of the KK-82MS scientific calculator documented so I can design a drop-in replacement PCB. Your job is to open the unit, trace every relevant signal, and give me a clear map of what connects where. The focus is on both LCD behaviour and the button-scanning scheme, so I expect you to show how each LCD segment is driven, which pins act as commons, how the microcontroller multiplexes them, and the exact keyboard matrix rows and columns the processor polls. Feel free to combine a logic analyser, multimeter, oscilloscope, or any other bench tool you trust; choice of instrumentation is up to you as long as the final data are unambiguous. Deliverables • High-resolution photos of the calculator fully disassembled, including close-ups of the flex cables and IC m...

I have a stable FreeRTOS-based firmware that currently compiles only under my portable Arduino IDE 1.8.13 setup for the SAMD51 MCU. I now want the project to build and run cleanly in the latest Arduino IDE without carrying along any of those version-specific hacks, board package pin-tweaks, or legacy library work-arounds. Once the codebase is modernised, the next step is to extend it with new sensors. You will receive the present firmware, board-support files, and the partial sensor drivers at project start.

Hello, **We only consider the QC from China only** I have a consignment of electric Product - Mosquito Diffuser that will be ready to leave the factory in Chengdu, Sichuan, and I need an experienced quality inspector on-site before it ships out. The task is strictly a pre-shipment check focused on two areas: visual inspection of workmanship and packaging, and functionality testing of the finished units. You will visit the factory on the agreed date, work alongside the production team without disrupting their flow, and provide an independent report that lets me decide whether to release the balance payment to the supplier. Scope of work • Visual inspection – confirm cosmetic finish, labeling, accessories, and carton integrity meet the approved golden sample. • Functio...

Looking for an Engineer with strong experience in industrial automation, control systems, and OT infrastructure. Freelancers should be proficient in following: ----->>> Configuration, maintenance and troubleshooting of HMI (C300, C300PM, UOC, HBM) ----->>> Support and troubleshooting of PLC systems and SCADA integration ----->>> Expertise in Control loop tuning and basic advanced control (PID) I am looking for experts from Pakistan only.

Hi, I'm looking for an experienced PCB designer to create a custom carrier/breakout PCB for a compact handheld device. No firmware or software needed — design only. Core Module: LILYGO TTGO T-Call V1.3 (ESP32 + SIM800L GSM) — mounted on the PCB via pin headers Components to integrate on PCB: OLED Display (SSD1306 128x64, I2C, 4-pin): Mounted above the PCB using standoff spacers — 4 mounting holes required Height will be adjusted with standoffs 4-wire cable from display soldered directly to PCB pads Buttons: 1x membrane switch connector (2-pin) for main button 2x additional button footprints connected to spare GPIO pins (for future use) Buzzer: Passive buzzer mounted directly on PCB Connected to designated GPIO via NPN transistor + flyback diode driver circuit ...

I need a complete hardware-and-firmware solution that blends a PIC microcontroller with Arduino-compatible modules on a custom-made PCB. The end goal is to streamline several industrial processes, and I also want the design flexible enough to drive lighting, heating & cooling, and security subsystems that resemble home-appliance automation. Here is what I envisage: • Schematic and PCB layout ready for fabrication, including a clean separation between the PIC control core and any auxiliary Arduino shields or sensor breakouts. • Embedded C / Arduino-style firmware that handles real-time control loops, sensor inputs, and actuator outputs for an industrial environment. • A concise BOM with component part numbers that are actually in stock. • Production-ready Ger...

I’m building a microcontroller-based system around an stm32 and need compact, reliable embedded-C firmware that lets me read multiple sensors and move their data cleanly through standard communication channels. The core of the job is classic microcontroller programming: bring up the chip, initialise the peripherals that the sensors require (typical I²C, SPI or simple GPIO timing), perform periodic reads, apply any basic filtering the devices recommend, then expose the results over the communication protocols we agree on—UART is mandatory; CAN or USB-CDC would be a welcome extra if time allows. You will be working with the latest STM32CubeIDE tool-chain, so please be comfortable with HAL and, where efficiency demands, direct-register work. I’ll supply full pin-outs, ...

We are a climate-tech company based in Coimbatore, India, seeking an experienced Electrical Control Panel Engineer or UL/CSA-certified Fabricator to design and build a compliant industrial control panel for export to Canada. The panel must meet UL 508A (USA) and CSA C22.2 No. 286 (Canada) standards. The system will power and control our environmental air-purification unit integrated with IoT/PLC components. Scope of Work: Design, fabricate, and document a complete industrial control panel using UL/CSA-certified components. Include a Main Power Cord (SOOW or SJTO type) and a UL-listed Circuit Breaker (Type C or D curve) for primary overcurrent protection. Integrate a DIN-rail mounted SMPS (24VDC output) to power either a PLC (Allen-Bradley/Siemens) or a custom PCB-based controller. Pr...

The original schematics and firmware sources for my existing motherboard are no longer available, yet I still need to keep the product alive and solve a series of recurring hardware failures. The immediate objective is to reverse-engineer the board in detail so I have a complete, accurate picture of how every power rail, I/O interface, and embedded controller is wired and programmed. Once that knowledge is captured, I want a refreshed design that removes today’s failure points and is ready for a short production run. Work starts with non-destructive teardown, high-resolution imaging, net tracing, and firmware dumping via JTAG/SWD or any other proven technique. From there the task moves into schematic recreation (Altium Designer or KiCad preferred), BOM generation with current compon...

Project Overview This project aims to develop a small WiFi gateway that connects to a Danfoss EKC 202C refrigeration controller via Modbus RTU (RS-485) and provides a local web interface. The system should allow monitoring of key controller values and limited control via a browser. The first version is a local-only solution without cloud connectivity, but the architecture must allow future expansion to cloud services. Hardware Assumptions • ESP32 or similar WiFi-enabled microcontroller • RS485 interface module for Modbus RTU communication • Connection to Danfoss EKC 202C controller (via Modbus adapter) Setup Flow • On first boot the device starts its own WiFi Access Point • User connects via smartphone or laptop • User opens configuration page at • Use...

I’m putting together an all-terrain rover that pairs a Raspberry Pi 5 with an Arduino. The Arduino will sit close to the hardware, polling and driving everything from temperature-humidity probes and distance sensors to an IMU (pitch/yaw/roll, altitude, compass), ESC-PWM motor controllers, speed-over-ground tracking and battery-management read-outs. All of that raw data needs to flow up to the Pi, where it is bundled, logged and pushed over a 4 G link. The Pi also runs the user interface on an onboard touchscreen. I want that interface to launch straight into a clean dashboard with drag-and-drop style widgets so I can rearrange or resize gauges, graphs and buttons while in the field. On the software side I need: • Firmware for the Arduino that publishes every sensor value pl...

I want to build a persistence-of-vision LED system that mounts on a standard bicycle wheel and shows crisp, full-color static images whenever the wheel reaches riding speed. The image should appear only at higher RPMs—cruising or sprint speeds—not while I am moving slowly or stopped. Core functionality • An addressable 256 LED spoke mounted strip driven by a small micro-controller (ESP32, Arduino-compatible, or similar) and powered by a lightweight, wheel-mounted battery. • Firmware that stores and renders static bitmaps in correct perspective as the wheel spins, synchronizing via hall-effect or magnet sensor. • A simple phone app that lets the rider pick any image, crop it to a wheel-friendly template, and wirelessly push it to the controller. There is no...

I’m building an automated live-play poker table and need the complete RFID hardware blueprint that will let software read every chip on the felt in real time. The table will hold well over 100 tagged chips at once, and I want reliable High-Frequency (13.56 MHz) reads at a maximum distance of about 10 cm from the antennas under the layout. Your task is purely on the hardware side: define an architecture that can see each chip as stacks move, bets slide, and pots grow, then pass clean data to the software team through a simple API or wired interface of your choice. Key expectations • Robust HF antenna array layout sized for a poker table, including multiplexing strategy to handle >100 simultaneous tags without collisions or dead zones. • Reader, controller, and MCU/FPG...

I need a compact 2-4 channel analog MEMS microphone array built around an XMOS processor. The board must perform real-time beamforming, echo-cancellation and noise-suppression, then expose a clean audio output through straightforward header pins so it can be patched into downstream hardware without fuss. Size matters here: the smaller the PCB, the better. I’m expecting you to handle the full hardware cycle—schematic capture, PCB layout, component selection and a ready-to-order BOM—plus the XMOS firmware that brings the DSP features to life. Your code should compile and run on the free tools from XMOS; please include any scripts or tuning utilities you rely on. Deliverables • Production-ready Gerbers, pick-and-place file, annotated schematic • BOM with supp...

I’m building a small-footprint PCB around the ESP32 that will serve as the core of several IoT devices. The board must expose reliable Wi-Fi, Bluetooth, and flexible sensor headers so it can drop straight into prototypes and low-volume production runs. Here is the scope I have in mind: • Schematic capture for the ESP32 module with stable power-management, antenna clearance, and USB-to-UART programming interface. • PCB layout (2-layer is fine if performance allows) that remains within 50 × 50 mm, ready for standard SMT assembly. • Breakouts or onboard footprints for common environmental sensors; I haven’t finalised the exact parts, so leave room on I²C and a couple of ADC/GPIO lines for temperature, humidity or motion modules. • Production...

My drone refuses to finish its latest firmware update and is now stuck in an endless restart loop. I need an experienced developer who has already dealt with drone firmware quirks to track down the root cause, flash the correct binaries if necessary, and get the aircraft flying again. The work is strictly troubleshooting: no new features or redesigns—just a clean, stable fix. While the main symptom is a failed firmware load, I’m open to your testing any related areas such as connection hand-shake or crash logs if you suspect they’re part of the problem. Deliverables • Diagnose the exact point where the firmware update fails • Apply or guide me through the corrective procedure (new build, bootloader tweak, or safe-mode flash) • Verify that the dr...

I’m integrating a NEMA-17 stepper into a small robotics prototype and need reliable position feedback. My current hardware stack is an Arduino Uno, a standard A4988 driver, and an incremental rotary encoder mounted on the motor shaft. What I need from you is a clean, well-commented sketch that: • Drives the stepper using the A4988, • Reads the encoder in real time, • Reports absolute position (in steps or degrees) over Serial, and • Lets me set a target position via Serial and have the motor move there, stopping within one encoder count. Please include a brief wiring diagram (hand-drawn or Fritzing is fine) so I can replicate your setup, and note any libraries you rely on beyond the Arduino core. I’ll consider the job complete once the code compi...

I have a multi-rotor nanodrone running ArduPilot that must fly semi-autonomously via GPS waypoints. The core of the job is to configure the ArduPilot stack so the craft can: • Accept a pre-loaded waypoint flight plan • Accept inject, delete, or reorder waypoints in real time through a long-range data link • Provide the FC ready to integrate: on-board camera, LiDAR, other UARTS devices • Execute a dependable Return-to-Home routine triggered by failsafe, low battery, or a command from the ground station I already have the flight controller, ESC, batteries, motors, associated wiring, and drone frame What I need is the firmware configuration, leveraging COTS Ardupilot and MAV-link. At power up, the drone shall arm and launche with minimal manual intervention, besides the...

PROJECT SUMMARY: I need an experienced RF/NFC hardware engineer to design a compact, modular 4×4 NFC sensor array board. The board will be used to detect and identify NFC-tagged objects placed on a flat surface (e.g., industrial tray, logistics sorting grid, or interactive tabletop application). Multiple boards (up to 6) will be tiled together to cover larger surfaces. Each board must detect and report the UID of ISO 14443 and ISO 15693 NFC tags placed on any of its 16 positions, within 500ms scan time for the full array. This is not a greenfield project. I have an existing but non-functional 6-layer PCB design (EasyEDA source files available) that attempted this with an ST25R3916B, STM32L476, analog multiplexers, P-MOSFETs, and PIN diodes simultaneously. The design is overenginee...

We are seeking an experienced Hardware Development Engineer to lead the end-to-end hardware development of a consumer-grade embedded system. The role involves system-level architecture, component selection, schematic design, PCB layout, and hardware validation in collaboration with the firmware engineer. The engineer must strictly adhere to the milestone plan and deliverables outlined below. Key Responsibilities: - System-level hardware architecture and design freeze. - Component selection (MCU/SoC, power ICs, storage interfaces, wireless modules). - Schematic design and PCB layout (high-speed + mixed-signal, EMI-aware). - Power integrity, grounding, shielding, and DFM/DFA compliance. - Prototype fabrication support and manufacturer Q&A. - Hardware bring-up support and validat...

I aim to develop a solution that will facilitate data communication between an Arduino UNO and a SIM7600E using AT+COMMAND. The primary data in focus will be temperature sensor readings. Key Responsibilities: - Setting up a reliable connection between Arduino UNO and SIM7600E - Implement AT+COMMAND for effective communication - Design a protocol for transmitting temperature sensor data Ideal Skills: - Solid knowledge of Arduino - Proficiency in handling SIM7600E - Experience in implementing AT+COMMAND - Understanding of sensor data transmissions. Please ensure you can efficiently deliver on these requirements, and provide the mentioned sensor data communication before placing your bid.