Pdm decimation filter. 06 dB overall, bandwidth is 21.

Pdm decimation filter. 557557098602e-07 ]; filtered_signal = zeros(1, length(pdm_signal)); for i = 1:length(pdm_signal) filtered_signal(i) = myFIRfilter(pdm_signal(i), impulse_response); end num_stages = 4; % Number of CIC filter stages differential_delay = 1; % Differential delay cic_filter = dsp. After that, it goes to infinite loop caused by watchdog. This method improved the alias rejection more than the original sharpened comb filter. In addition, the simulation part illustrates how to verify the results of a design, and finally, deploy it onto a specific FPGA hardware platform 1. For computational efficiency, the filtering is sensibly combined with a decimation stage to reduce the sample rate to one suited to the finished audio. This is to check which instruction caused that . CICDecimator(decimation_factor, num_stages, differential_delay); The data coming from the microphone is sent to the decimation process, which consists of two parts: a decimation filter converting 1-bit PDM data to PCM data, followed by two individually configurable IIR filters (low pass and high pass). Mar 10, 2020 · The filters (float numbers!) are stored inside the mat-files together with the PDM and PCM sampling rates. At 1/32 decimation (green trace), 96 kHz of bandwidth is available. Decimation filter In order to convert the incoming data stream into PCM audio samples, a decimation filter is included in the PDM peripheral. Processing complexity: PDM signals cannot be used as-is as audio and require a decimation filter (process to remove high-frequency components). The embedded decimator is designed to be 24-bit, so it is recommended to use the 24-bit mode. The decimator-filter function The second function of the digital/decimation filter is the decimator. The PDM2PCM library has the function to decimate and filter out a Pulse Density Modulated (PDM) stream from a digital microphone, to convert it to a Pulse Code Modulated (PCM) signal output stream. Again, all of this work was not in real-time. Jul 9, 2023 · At the moment we are only interested in analog to PDM and PDM to analog conversion with a low pass filter as digital to analog converter. The decimation filters are designed to filter out this noise, leaving the baseband audio signal intact. For the 16-bit mode, utilize the right shifter and the saturation configurations to protect from rollover while maintaining 16 bits by downshifting by 8. Note the rise in the noise floor starting just below 30 kHz. 有哪位老兄来帮忙解释一下decimation filter的工作原理呢? Thanks you in advance. In practice, to keep the data rate compact you may also want to perform decimation. pdm_mic_decimation_1. The dsp. The output of the decimator is a PCM audio stream at the baseband (non-oversampled) rate. I use CIC decimation filter. Each filter in the pipeline is implemented with the Amaranth HDL as an amlib library. 0) works? Collection of miscellaneous tools for PDM signals generation, acquisition and decoding - siorpaes/pdm_playground The CIC decimation filter is conceptually given by a single rate CIC filter, H (z) which is a lowpass anti-imaging filter, followed by a downsampler. Jun 2, 2025 · This is known as oversampling. Low pass cutoff is decided based on what highest frequency you want to keep in the resulting PCM. To get to our original sampleFrequency we need to ultimately use one sample out of every 64 we see in the PDM pulse train. The decimation filter decimates the bitstream by ABSTRACT This application report helps system designers demonstrate and understand the technique of directly feeding a MEMS mic output PDM stream into the Inter-IC Sound (I2S) lines of a C5515 EVM. This is the noise shaping of the sigma-delta modulator in the microphone. Use a terminal program on your PC to observe the data. This article demonstrates one such FPGA PDM-to-PCM conversion system using Cascaded Integrator-Comb (CIC) filters and Finite Impulse Response (FIR) filters, implemented on an Intel Arria V GX FPGA by our group. Common settings that balance these tradeoffs are presented. This decimation filter is implemented in the codec or DSP to which the PDM microphone is connected. EasyDMA is implemented to relieve the real-time requirements associated with controlling of the PDM slave from a low priority CPU execution context. A sinc filter (e. The CIC decimation filter decreases the sample rate of an input signal by an integer factor using a cascaded integrator-comb (CIC) filter. It consumes 12 multipliers when 24-bit width Abstract: A digital decimation filter applied to audio Sigma-Delta ADC is designed. I found the STM32U5 has hardware-based digital filtering using a peripheral called Multi-function Digital Filter (MDF) which I was optimistic about until it dawned on me that the decimation filters are SINCx. 1 Goal Find the optimal setting for the PDM-DECIMATION audio path. Measurements are without A-Weighting or AES-17 filter unless otherwise noted. Design guidelines are provided with the aim to simplify the design of the constituent decimation filters in the multistage chain. Pass the generated data structure and the base address to the associated pdm_pcm driver function in the application initialization code to configure the peripheral. g. However, the results I am obtaining are not as expected. The current system can process data coming from two PDM digital microphones at the same time and output PCM data using GPIO pins. Sinc filters are a subclass of FIR filters that have a specialized, computationally efficient implementation. Cascaded-Integrator-Comb (CIC) filters are by far Feb 19, 2025 · Part Number: PCMD3180 Tool/software: Hi, We're considering using the PCMD3180 in our system, but we have some questions: 1. 048MHz/128 = 16kHz. , 16-bit samples at a 16 kHz sample rate), the PDM signal must be processed by a decimation filter. The sigma-delta architecture of the PDM microphone implies a filtering and a decimation of the bitstream at the output of the microphone bitstream. Is this code correct? void LowPassFilterWithDecimation (uint8_t *pdm1, uint8_t Jun 2, 2021 · It documents the filters used the decimation ratio at each of the three stages and the performance of each stage of filtering and overall. 请问什么是decimation filter ? 2. Sep 4, 2022 · Does anyone have advice on efficient CIC Decimation filter implementation. Mar 26, 2020 · After describing a few applications of CIC filters, this blog introduces their structure and behavior, presents the frequency-domain performance of CIC filters, and discusses several important practical issues in implementing these filters. 5 BRAMs Previously, Low pass decimation filter structure (FIGURE 3) widely used for decimation before appearance of the CIC decimation filter (Adams 1994). The output of this filter gives data at a lower sample rate, typically between 16 and 48 kHz. HW decimation filters Selectable ratio of 64 or 80 between PDM_CLK and output sample rate The PDM module illustrated below is interfacing up to two digital microphones with the PDM interface. out_ptr PDM to PCM Conversion The PDM task performs decimation and low-pass filtering to convert the raw PDM data into high-quality PCM (Pulse Code Modulation) audio samples. The values set by an output buffer in the function PDM_Filter (). examples/gsd_butterstick. Input data size for one PDM_Filter is 'Output data * 64 / 8' The 64 is decimation factor. Hence, the implementation of a resource-eficient CIC decimation filter is very much important in signal process-ing. application of a low pass filter 在开始处理前必须至少调用一次PDM_Filter_setConfig(),以设置可配置参数 此外,由于PDM2PCM 库在STM32 设备上运行,因此必须使能并重置CRC HW块。必须分配静态和动态参数结构。在pdm2pcm_glo. Feb 19, 2024 · Hello everyone, I am currently attempting to convert PDM data (from a MEMS CMM-4030DT-26354) to PCM data using the libPDMFilter_CM7_IAR_wc32 provided by STM32Cube. I am not able to understand that I should set the value to output_samples_number. If it's helpful, I did a presentation at AES a few years back on FIR filtering which demonstrated some of the techniques used to efficiently implement a PDM to PCM converter. Sep 20, 2024 · mems数字麦克风大致都一样，VDD和GND，时钟脚CLK，左右声道选择L/R，数据线DATA，当然这是输出PDM数据的麦克风，也有I2S接口的数字麦克风，他会多一个引脚，就是WS。 . Overview The MCUXpresso SDK provides a peripheral driver for the Microphone Interface (PDM) module of MCUXpresso SDK devices. PDM-to-PCM conversion requires a decimation filter to suppress high-frequency noise. In a PDM signal, specific amplitude values are not encoded into codewords of pulses of different weight as they would be in pulse-code modulation (PCM); rather, the relative density of the pulses corresponds to the analog signal's amplitude. I tried to integrate this libr Feb 17, 2021 · Hello, I am trying to understand how the PDM_Filter () function works. Are there some resources where I can read about the type of filtering and what\\u0026#39;s the difference between 16x decimation ratio and 32x decimation ratio. Aug 24, 2024 · Hi, \\n I am looking at the ADAU7118\\u0026#39;s datasheet and am hoping to know a little bit about what happens inside the \\u0026quot;Digital Decimation Filtering\\u0026quot; block. Dec 2, 2020 · For this purpose, it first reviews the state-of-the-art decimation filter design methods and proposes an algorithm to design decimation filters optimizing area and power consumption. We've utilized the CIC filter as a primary component and provided source code support for flexible input parameter adjustment. Dec 27, 2022 · I am trying to decimate a PDM signal in order to obtain a PCM signal. The calculated volume is sent over the UART. The 8 is for bits. 0). The Minized has very few resources so we won't be able to take very large samples but it will help us to debug our system. PDMmic provides a simple PDM microphone interface. Please refer to the TRM to check how many hardware channels are available. At 1/512 decimation, only 3 kHz bandwidth is available (blue trace). Apr 30, 2024 · 我在使用STM32WBA55G-DK1板子调试SAI接口，SAI连接了一个数字麦克风，数字麦克风提供的是PDM信号，ST提供了一个 PDM2PCM 库进行转换，但是我的工程发现转换出来的PCM数据都是0，为了验证是不是我的PDM数据有问题，我从这个官方提供这个板子的Demo工程里获取SAI获取的 Abstract - The purpose of this paper is to present several filter topologies used for decimation of sigma delta modulated digital signals in order to choose the optimised filter architecture with regards to an efficient implementation. 06 dB overall, bandwidth is 21. This filter attenuates low frequencies that add offset to the conversion. Chebychev type 2). Q: Is there a decimation rate I should use? Normally the decimation rate to Dec 31, 2022 · Hi, PDM can simply be low pass filtered to get the PCM. Decimation: Reduces the sampling rate of the signal. Does that mean if i set the PDM CLK manually, and provide a FSYNC and BCLK, then it would set the division ratio . CIC is a filter structure which will perform FIR + decimation. The data coming out of the microphone is sent to the decimation process, which consists of three parts: a CIC decimation filter converting 1-bit PDM data to framed data, followed by two 2:1 half band filters and an FIR filter in the final stage eliminating the high frequency noise generated in the sigma delta modulation process in the Microphone. I'm confused at this point: What should be the data type in the filter input? This is why decimation is also typically done during PDM to PCM conversion, because the bandwidth is being chopped way down and no longer needs the high PDM sample rate. Functional APIs can be used for PDM initialization, configuration, and operation for the optimization and customization purpose. 为何需要他?3. 以PDM方式作为模数转换的接收端，需要用到抽取滤波器（Decimation Filter），将密密麻麻的0和1代表的密度分量转换为幅值分量，即PCM格式。 故一般单片机的PDM接口实际上是一个PDM格式转PCM格式的功能。 为了将PDM流转换为PCM样本，需要对PDM流进行滤波和抽取。 May 15, 2016 · Overview of how to interpret a PDM audio stream from a MP45DT02 microphone using the I2S hardware on a STM32F407 MCU. 1 dB and stopband attenuation of 120 dB Input sampling rate and PDM clock frequency 3. May 19, 2017 · Hi, We don't have any full examples yet. A decimation filter is defined as a filter that bandlimits an input signal prior to downsampling to prevent aliasing, ensuring that the output signal retains the shape and energy of the original signal within a specified frequency range. 0. Aug 31, 2023 · However, as the ΣΔMs output a PDM signal, sensors require either built-in or external high-order decimation filters to demodulate the PDM signal to a baseband multi-bit pulse-code modulated (PCM) signal. The PDM/PCM hardware block is also configured to enable a high-pass filter. Using the functional API requires the PDMmic provides a simple PDM microphone interface. An IIR filter will have many fewer taps for the same transition bandwidth: you probably will want a flat-passband filter like a Butterworth or Chebyshev Type 2. hypothesis: 1) using a library not for Cortex-M33 / M4 should work also , but to check secure / non secure parts 2) Initialization is missing some hardware configuration 3) used library for PDM not ready for H5 Oct 3, 2016 · Learn how to implement signal decimation on an FPGA with Xilinx CIC and FIR compilers. The decimation ratio defines the relationship between the PDM clock frequency and the baseband rate. A MEMS microphone package is unique among semiconductor devices, in that there is a hole in the package for the acoustic energy to reach the transducer element. The word “decimate” was originally used by the Roman army to mean the killing of every tenth man of a group that was guilty of mutiny. Jan 2, 2025 · Simple hardware configuration: PDM is often used for low-cost microphones with simple wiring. 048MHz with an Over Sampling Ratio (OSR) of 128, the targeted sampling rate is 2. Extracting the audio from it merely requires a suitable low-pass filter to reject the noise. Jan 30, 2016 · PDM Decimation Our PDM signal has a sampling frequency of 64 × sampleFrequency or 65. This filter, usually implemented in hardware on the codec, is what reduces the high sampling rate used for the PDM data to the baseband audio sampling rate and converts the 1-bit PDM data stream to a multi-bit data word of usually at least 16 bits. The digital filter also removes out-of-band frequency components (for example: quantization noise or unwanted signal), and reduces the data rate by decimation. The filter is suited for data conversion and measurement applications. PDM-to-PCM conversion requires com-plex high-order filtering and high values of decimation factor, which hardly fit resource constraints for in-sensor comput-ing [12], [13]. I set, decimation_factor = PDM_FILTER_DEC_FACTOR_64. Pulse-density modulation (PDM) is a form of modulation used to represent an analog signal with a binary signal. The codec’s PDM data inputs are connected to a decimation filter block in the codec IC. 6 kHz, minimum working frequency is 10 MHz. While most converters have one sample rate, the DS con HW decimation filters Selectable ratio of 64 or 80 between PDM_CLK and output sample rate The PDM module illustrated below is interfacing up to two digital microphones with the PDM interface. This paper proposed CIC decimation architecture with the bit-pruning method and also partitioned the decimation factor into two parts. The current hardware-based PDM-to-PCM converters uses cascaded integrator-comb (CIC) based and finite impulse response (FIR) filters, which result in high hardware utilization to achieve a high Feb 4, 2018 · Hi STCommunity, I'm using a Nucleo F446RE and I have to convert a PDM bitstream from a pair of mems microphones (CCA02M1 eval board) intoPCM. Bits in PDM stream can be encoded as 1=> +1 and 0=>-1 and this corresponds 2bits signed number (S2. May 12, 2023 · The output from a digital Micro-Electrical- Mechanical System (MEMS) microphone in the form of PDM often needs to be converted to PCM before further processing, as PCM signals are easier to analyze. Higher PDM frequencies allow wider audio bandwidth but increase power consumption, while lower ratios filter more noise but may require higher PDM frequencies. Example with a PDM rate is 2. Aug 18, 2000 · CIC decimation filters decimate the signal by D CIC and convert the PDM signal in PCM at the same time. 1 Delta-sigma modulation converts an analog voltage signal into a pulse frequency, or pulse density, which can be understood as pulse-density modulation Feb 22, 2012 · Before this PDM data can be further processed, it needs to be decimated to a lower sample rate that other devices, such as codecs and DSPs, can handle. Each time the PDM_Filter function is called it will convert Input date and produce output date. We assume that a more efficient implementation could be realized using IIR filters at the cost of potentially inaudible phase distortions close to half the sampling frequency (e. The filter input is a two-channel PDM serial stream (with left channel on clock high, right channel on clock low). I designed a basic 4th order CIC filter with a 64 decimation ratio in C (below). This document is intended for audiences familiar with Digital Signal Processing, decimation and filtering techniques. Functional APIs target low-level APIs. The output of a 1-bit DAC is the same as There is a filter structure that combines the sinc filter together with the decimation called the Hogenauer CIC sinc filter. The decimation filter decimates the bitstream by Apr 21, 2021 · 0 In order to convert the PDM stream into PCM samples, the PDM stream needs to be decimated. Nov 29, 2024 · Hi, I am struggling to make PDM2PCM library work. If the signal bandwidth is quite narrow, you can get away with a reasonable-sized FIR filter. The filter adopts the design of multi-stage and multi-rate down sampling structure, in-band ripple of decimation filter is less than 0. The data coming from the microphone is sent to the decimation process, which consists of two parts: a decimation filter converting 1-bit PDM data to PCM data, followed by two individually configurable IIR filters (low pass and high pass). The decimation factor, endianness, and bit order are now configured once at the PDM_Filter_Init() function call Decimation factor, demodulation loop size and digital gain can be changed on-the-fly using PDM_Filter_setConfig() function Jan 15, 2002 · pdm decimation filter I design a decimation filter(in verilog) for a 1-bit oversampled sigma-delta ADC. From what I understand a cic filter is built on the concept of an average moving window. I am currently testing this on a Sharc SC The PDM audio stream used in the Table 4was generated by the APx525 PDM Module, with a 5th order noise shaper. CICDecimator System object decimates an input signal using a cascaded integrator-comb (CIC) decimation filter. We need to make sure the Division ratio in the decimation filter >=128. The filter's gain is adjusted to preserve the values of the samples that will be kept during the downsampling process. -3. The digital/decimation filter then takes this sampled data and converts it into a high-resolution, slower digital code. AI generated definition based on Feb 5, 2025 · 本文从抽取（Decimation）讲到 Moving Average，再由 Moving Average 讲到 Sinc Filter，其硬件实现叫做 CIC Filter。 Dec 10, 2009 · 1. The rest of the audio system can natively process this The sigma-delta architecture of the PDM microphone implies a filtering and a decimation of the bitstream at the output of the microphone bitstream. We also added an Integrated Logic Analyzer IP block. Does anyone know how the latest PDM2PCM library (rev. Mar 2, 2022 · I tried to use the PDM2PCM library in the STM32L432. If not library will not work. Index Terms—A/D converter, CIC, cyclotomic, comb, decimation, decimation filter, multistage, polynomial, sigma-delta, sinc filters. A second order 1-bit sigma delta modulator will be considered as the front-end A/D PDM demodulators c) and d), which are proposed in [19] and in [14] respectively, present a cascade of three different type of filters in a filter chain fashion, that is, a CIC decimation filter A PDM-based architecture differs from I2S and TDM in that the decimation filter is in the receiving IC, rather than the transmitting IC. We must use values in the output buffer (= PCM data stream) as uint or int ? 2. 536 kHz. The PDM will take a bit stream (in out buffer stored in bytes so this is the /8 The first processing stage is a 4th order CIC decimator with decimation rate of 32 or 64, followed by an half-band decimator and DC-offset canceller using floating point arithmetic. It consumes 12 multipliers when 24-bit width The Component generates the configuration structures and base address described in the Global Variables and Preprocessor Macros sections. I have some questions about PDM2PCM library. The filter implementation has a strong influence on data output resolution and quality. If I am using 48Khz with a decimation factor of 64 and a output samples = 16 If 本文从抽取（Decimation）讲到 Moving Average，再由 Moving Average 讲到 Sinc Filter，其硬件实现叫做 CIC Filter。 根据 Sinc Filter 频谱通带窄、硬件成本低的特点，通常用于从数十到几千 Hz 的低频输入，对应如温度、压力、人体生理等缓慢变化的传感器应用。 Sep 2, 2015 · The client is converting the PDM signal to a PCM signal in the following way: > > /* Buffer PDM signal for further processing and decimation */ > for (i=0;i<N;i++) > { > tmp=0; > for (imod=0;imod<16;imod++) > { // Decimation factor 16 > tmp+= ( (pdmSignal [i+imod]>>2)&1); > } > > k++; > buffer [k]=tmp; > } > > > /* Low-Pass Filter Signal To Types of Digital Filters In general, there are three basic types of digital filters: finite impulse response (FIR) filters, infinite impulse response (IIR) filters, and sinc filters. CIC Filter Applications CIC filters are well-suited for anti-aliasing filtering prior to decimation (sample rate reduction), as shown in Figure 1 (a); and Apr 18, 2022 · Seemingly the only MEMS microphones that are up to par have PDM output so now I am learning about PDM->PCM conversion. In the decimation circuit, the Feb 27, 2023 · I would like to convert PDM (Pulse Density Modulation) microphone data into PCM (Pulse Code Modulation) data. PDM-based architecture differs from I2S and TDM in that the decimation filter is in the receiving IC, rather than the transmitting IC. The output of the source is the raw high sample rate modulated data, such as the output of a Sigma-Delta modulator, rather than a decimated data, as it is in I2S. Once the peripheral is initialized, the application code can perform run-time changes by Oct 6, 2023 · I started with a data set that I collected using a logic analyzer, started playing around with elementary filters (eg, running window), and eventually found my way to CIC filters for decimation. Ideally, the audio wave captured should oscillate around zero. PDM driver includes functional APIs and transactional APIs. I implemented a crude filter in Python, and the data output looked great. I am expecting a 1000 Hz sine wave tone, but instead, I am getting what appears The I2S microphone contains all of the digital circuitry that a PDM microphone has, as well as a decimation filter and serial port. However, as the ΣΔMs output a PDM signal, sensors require either built-in or external high-order decimation filters to demodulate the PDM signal to a baseband multi-bit pulse-code modulated (PCM) signal. py is a running example using LiteX on Greg Davill's ButterStick board. h" #define CONFIG_PDM_BUFFER_SIZE_SAMPLES 320 // <o> PDM Decimation Filter Gain <0x00… Mar 31, 2021 · Output of a PDM microphone @ 3. Important the CRC unit must be enabled. Through my research I keep coming back to the topic of cic filters for high rate decimation. Nov 4, 2014 · Finding the signal The PDM signal contains two components: an audio signal, and a high frequency noise. 1. 072 MHz bitrate. CIC is efficient as there’s no mult involved in the operation! CIC has two parameters M and N The DS converter’s primary internal cells are the DS modu lator and the digital/decimation filter. zip Sep 12, 2023 · I was told, by the manufacturer, that I need to implement a decimation filter, which includes at least a 4th order low pass filter. h头文件中定义其类型。分配示例: The size of your decimation filter will depend on how wide the transition band can be. The reconstructed audio is in 16-bit pulse-code modulation (PCM) format. In this project, we implement a simple PDM to PCM converter (PDM2PCM) based on the Migen FHDL library and LiteX toolbox. The project cofigure the PDM2PCM filter. Requires Decimation and Filtering: To convert the 1-bit high-frequency PDM stream into a usable multi-bit PCM audio format (e. It eliminates the need for the data buffers and has a very cool way of un-wrapping data that has wrapped around in an open-loop cascade of integrators. , \ (\text {sinc}^3\)) is commonly used, but its group delay and computational cost scale with filter order. The implementation of PDM to PCM filter pipeline is based on Tom Verbeure's articles for PDM to PCM conversion. 请问什么是decimation filter ? ,EETOP 创芯网论坛 (原名：电子顶级开发网) Jul 26, 2024 · Dear @Nagarajan , can you please have a screenshot on the Hardfault location and trace/log of the stack when at Hardfault while (1) . Dec 19, 2012 · hi,, i am doing a project on SOFTWARE DEFINED RADIO in which i am using a CIC filter which is implemented in FPGA. This structure has M Multipliers which make the large number of computation whereas new structure of decimation or CIC is multiplier less in terms of minimizing hardware and computational. My projects build without issues, but when I upload them to the board , program executes until it reaches PDM_Filter_setConfig function (tested with breakpoints). I cant seem to find any info on this in the datasheet, as it states its automatic. 3. Oct 18, 2021 · A FIR lowpass filter with 3500 taps with transition from 12kHz to 16kHz, passband ripple of 0. Decimation filter In order to convert the incoming data stream into PCM audio samples, a decimation filter is included in the PDM interface module. 55kHz sample rate with minimal aliasing Final resources: 2 DSPs 3. 125 MHz You just downsample the filter output by 96 to end up with 32. But here is some code to get you started: #include "nrf_drv_pdm. The performance results are limited by the measurement equipment and not the design. In the case of the digital/ decimation filter, the “decimation” of the digital filter’s samples is much more dramatic. I understand that there are 2 steps in this process. And hence i need to write a verilog code Contribute to VictorTagayun/STM32_PDM2PCM_PDM-Stream_to_PCM-Processing development by creating an account on GitHub. A filter with a narrow passband does usually require a large number of coefficients with a FIR filter, but there's no driving rule of how long it has to be. Sigma-Delta Modulation (SDM) [中文] Introduction ESP32-S3 has a second-order sigma-delta modulator, which can generate independent PDM pulses to multiple channels. But I don't have any idea to verify it. The internal DS modulator shown in Figure 1 coarsely samples the input signal at a very high rate into a 1-bit stream. Could anyone give me a hand? Thanks a lot! Each PDM data pin must be assigned to either the PDM_CLK0 or PDM_CLK1 clock sources, using the decimation ratio and PDM clock mapping controls register (DEC_RATIO_CLK_MAP), to ensure compliance with timing specifications. This process must be implemented programmatically, which increases the burden on software. bnik 1y 0wp2 lhykftb cnaw6 ulf fn8v u7c lh3dk ywvox