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0

i belive that what your looking for is a BadUsb or some variation of it, thn just customize the code a little to fit your needs.


0

In absence of specific reference designs for this IC in the documentation I'm using elements from CM108 design and Cmedia's FAQ. Will see how this plays out in prototype.


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You want a keyboard adapter or keylogger or man in the middle attack. A microcontroller or SOC that can do usb peripheral as a usb hid keyboard, and that can either do PS/2 reading or USB host for a usb hid keyboard. The PS/2 reading is much easier. Some modern usb keyboards still work with a USB to PS/2 physical adapter. A RPi can do it as it has usb host ...


0

The right sequence in assembly (for stm32l4) movw r9,#OTG_FS_L movt r9,#OTG_FS_H add r8,r9,#TX_FIFO0_STR ;(TX_FIFO0_STR equ 0x1000) mov32 r1,#(PKTCNT_CNT_1PACK+0x12) ;1pac size 18 str r1,[r9,#OTG_DIEPTSIZ0_B] ldr r1,[r9,#OTG_DIEPCTL0_B] orr r1,#(EPENA|CNAK) str r1,[r9,#OTG_DIEPCTL0_B] ;send prepare mov r1,#0x0112 ;len=18 +dev_id=1 ...


1

By using a multimeter and some common sense, we can: Ignore the colors. Check the expected pinout for the particular USB connector. Likely 1) +, 2) D+, 3) D-, 4) GND. Use a multimeter to tell which wire that happens to be connected to which pin, then connect them accordingly.


4

A lot of USB devices such as keyboards or mice have a captive cable which either has a custom connector is directly soldered to board. The Micro USB connector itself plays no role in the data transfer.


0

This is strange but probably the standard doesn't mandate the colours on the cable. However it mandates the cable specification. The two power cables (usually black and red) are of bigger cross section, while the data cable is a twisted pair. A simple multimeter on ohm or continuity will find the correct pairing. However if you simply hope to tie two cable ...


0

Are "ESP_EN" and "EN" connected? That aspect is needed for the truth table functionality of the two transistors to work.


5

In your case, yes. The CP2102N TXD is an output, and RXD is an input. The MCU you don't mention, but all MCUs I've seen so far have had MCU TXD is also an output, and RXD is an input. So since an output connects to an input, you connect RXD to TXD. Sometimes, the naming can be different, such as a pin is named TXD as input because it kind of says to connect ...


28

RX and TX cause all kinds of trouble because the naming is not totally consistent. In some cases, devices which are intended to be peripherals to a host will use host-centric naming. This means that the peripheral device will have an output called RX which is intended to connect to MCU RX input. And likewise it will have an input called TX which is intended ...


9

In general, you can't safely make assumptions either way, about the labelling of communication pins that swap meanings between partner devices. A pin named "TX" on some arbitrary "downstream" device might mean "connect this to TX on the upstream device", or "this pin is used for transmitting (connect it to RX on the ...


2

Power available from USB: 5 V * 2 A = 10 W. The monitor needs up to 18 W. So your monitor is likely asking for more power than the power bank can deliver. Is it too high of a power consumption to work with the converter cable. The cable is not just a cable, it contains a DCDC converter. You did not include any specifications of that DCDC converter so it is ...


0

am trying to build a circuit which provides 3.3V power to a micro-controller (Nordic Semi nRF52840). Absolute maximum range of voltage should be 1.8V to 3.6V. Maximum power consumption would be 140mA. It should use battery power when USB is not connected and use USB power when connected (ideally without resetting). Efficiency is not super critical because I ...


0

You need to be very careful when you find designs out there. The best option for you is to follow de hardware guides from the Manufacturer https://www.espressif.com/sites/default/files/documentation/esp32_hardware_design_guidelines_en.pdf You need to be able to differentiate the module and the IC though. Some circuitry is required if you want to build from ...


1

I decided to replace it in the next revision with a Type B connector, which is THT, thus providing greater mechanical support. This is quite weird decision. There are plenty of Micro B sockets with THT prongs on the shield, like this one, for example. It still has SMT signal lines, so there is no need to redesign board much, just add two or four mounting ...


4

The document you linked says this: - Does that help you? Can you place ground between or can you route on different layers separated by a ground plane? See also section 7.2 of that document.


1

Most of these USB to UART devices has ability to operate a variety of features for RS232 systems. They are used to send signals or receive signals back from devices for proper operation. You wont need them if you are using it to program a ESP32 module. For that, you will only need RX(Receive Data), TX(Transmit Data), RTS(Request to Send), DTR(Data Terminal ...


1

Since the product came with standard USB type A plug, the fifth wire would be connected to the metal chassis frame shield of the connector.


0

The 5th pin is the ID (or "sense") pin. Look HERE. It's purpose is to select which device is host and which is slave. This is often called OTG or On-The-Go. Here is an example. The type-A connector is on the right.


2

I'll try to shed some light here. This question is nothing but a can of worms. USB specifications do not define nor approve any passive/inductive/capacitive components along the USB transamission lines. The line must maintain 90-Ohms DIFFERENTIAL impedance over all essential frequencies to be useable and have a certifiable eye diagram. So-called "...


1

Commonly these kind of small coils and ferrite beads meant for data and power supply filtering all have their rated impedance measured at 100 MHz. The fact that a part suggested for 90 ohm differential signal happens to have 90 ohms impedance at 100 MHz can be pure coincidence for example reasons, as commonly parts like these are available at various ...


0

Common mode chokes manufacturers' write all data in the datasheets. The most important data in this case is Z as function of frequency. One should look at the graph Z(f) when selecting a choke. To answer your question: Manufacturers, to summarize the performance of their chokes, decided to use 100 MHz as a reference frequency. Why 100 MHz? Maybe because it's ...


2

My guess (or how I would do it) is that there are multiplexers on the data lines of both USB ports, and then check which port is being connected to the computer using power sensing in order to switch the multiplexers from each USB port to the correct pins on the USB2422. Those look like they could be multiplexers:


-1

You may use NXP's LPC17XX or LPC18XX devices. They are ARM based micro controllers. There are many examples for both USB host and device modes. Some examples were written from Keil. I used USB host and device of LPC2388 and LPC1778 and I got no problems at all. I was able to read and write flash drives. I was able to attach my board, as a hard drive, to my ...


-1

You can achieve that with some PIC32 devices which have 2 USB ports. The Microchip Harmony stack, however, is not properly tested/working (despite what advertized) when working with both ports at the same time in host/device configuration. You may need to implement your own USB stack or use some that are available online. In my case, I used Harmony stack for ...


0

I understand each track can be 45 Ohms so differential is 90 Ohms. A coplanar differential raises the diff impedance while lowering Zo with adjacent grounds so it needs a thinner height of dielectric. (5mil prepreg) But in your case if using a 10 mil dielectric; Impedance is almost constant ratiometric to the conductor geometry ratios if <2:1 ratios for ...


0

RS485 is the right answer for your problem. It's master-slave interface meant for fairly high speed (up to 10 Kbyte/s) and long distances (up to 1 km). Slave devices can be wired in parallel. It requires a UART interface on the microprocessor. All microprocessors have at least one. It requires a very simple software stack that you may find by googling: "...


0

If you want to multiplex your devices using the USB interface, make sure you: Have an external USB hub or The data collector system has USB hub on-board USB is a 1:1 peer-to-peer interface. ou can't just wire in parallel the extarnal devices.


1

The picture is correct. M means minus (-) and P means plus (+) so this is not the issue. Data+ must be connected to Data+, and Data- must be connected to Data-. It seems that the downstream and upstream ports are the wrong way though.


1

Looking at the specifications of that Dremel it seems to have a battery voltage of 4.8V using NiMH technology. Which sounds like 4 cells in series to me at a nominal 1.2V. Now nominal voltage is not charge voltage to fully charge it the battery voltage should reach closer to 1.6V per cell or 6.4V for the device. The included adapter was probably unregulated ...


1

Yes, but no. The leads are very thin, so you need to accommodate some form of stress relief, if not they will break if you sneeze in the room next-door. This stress relief will probably need as much, if not more, real-estate on the board as a connector. Secondly most USB leads isolation are made of PVC plastic that will melt as you solder. This will almost ...


1

Here is Intel's recommendation. Common-mode chokes degrade the signal but may solve an EMI problem. Finding a common mode choke that meets the designer’s needs is a two-step process. A part must be chosen with the impedance value that provides the required noise attenuation. This is a function of the electrical and mechanical characteristics of the part ...


1

Drivers impedance is generally lower than the USB cable impedance giving some tolerance to DCR for the CM choke. But a higher impedance CM choke like 500 Ohms with 5 Ohms DCR will greatly improve CMRR and should not interfere much with signal integrity yet give better immunity. This should improve signal damping as well but may limit BW on the fastest USB3. ...


1

Solved it. I just cut the wire, soldered a 3.5mm jack, plugged into my phone and it did work. Very low volume tho. But that's another issue. cheers!


0

If it’s an obsolete Kaliber product ( not on their website) call for tech support. Toll Free: 866-9-IOGEAR (866-946-4327) Local: 949-453-8782


1

Simply, you need a step down voltage converter. One common one is called LDO, those are device are dropping the voltage at a set value by dissipation. The advantage is that they are small, you only need a single component and they are cheap. However, the conversion efficiency is low as the energy is wasted. Another are called step down buck converter. Those ...


1

Dual-role USB ports were introduced in so-called "On-The-Go" (OTG) supplement to USB specifications. (still cannot figure out what OTG means). The role swap came at the expense of introducing one extra pin - ID pin. Therefore originally only mini- and micro-USB ports can provide the swap function, and Type-A can't provide the swap. Additional ...


4

Encoding of characters into digital data streams is rather older than Apollo. Émile Baudot's system was patented in 1874, about the time when Jules Verne was writing of the US sending a ship to the moon in the immediate postbellum period. The USB communication system used for the Apollo mission integrated a bunch of different data and analog streams. Digital ...


4

Dig in here: ftp://ssh.esac.esa.int/pub/ekuulker/Apollo15/The-Apollo-Guidance-Computer-Architecture-and-Operation.pdf And here: https://arstechnica.com/science/2020/01/a-deep-dive-into-the-apollo-guidance-computer-and-the-hack-that-saved-apollo-14/3/ tl; dr: a bespoke binary stream format for telemetry uplink and downlink.


0

This differential driver has outstanding balance so the CM emissions are limited only by the imbalance of the cable. If you had a spec. for short field emissions, which was critical, you could use a Raised Cosine LPF filter on the Tx data with zero ISI.


2

Yes, they usually have a lightning bolt symbol next to them: This symbol isn't in the USB spec, but it's a common convention: The USB charging port is on the front panel, and can be identified by the lightning bolt icon … This port follows the USB-IF’s USB Battery Charging Specification v1.2 (USB BC 1.2) … Charging Downstream Port (CDP) CDP is not only ...


0

It is not clear from the question if the LVDS line is full-duplex or half-duplex. In the first case simple full-duplex transceiver (like SN65LVDS179) connected to TX/Rx of the USB-UART adapter is all you need. In the second case you'd need M-LVDS transceiver (something like SN65MLVD206B). The DE/!RE lines can be connected to handshake/flow control pins of ...


0

You can convert the USB dongle's TTL signals to LVDS levels using a conversion IC such as this one: https://www.ti.com/lit/ds/symlink/sn65mlvd200a.pdf Note: LVDS isn't 'current loop' per se. It works on voltage. You could also set aside some pins in your FPGA that convert from TTL to LVDS, assuming you follow the voltage standard banking rules. When you're ...


5

Typically an UART does not include a PHY, and thus any external PHY can be used for implementing the communication bus. So feel free to select any suitable PHY for this, there are a lot of PHYs that implement low EMI by using a differential connection or limiting the slew rate. The PHYs include RS485, CAN, in addition to LVDS of course.


0

I recall this was an issue with some recent Samsung phones which was corrected with a software and/or firmware update. Check with Samsung on if there are any updates for your phone. The other possibility for your problem is that the phone requires a Quick Charge power adapter for more than a trickle of charge by USB-A chargers. Check what kind of charger ...


1

USB C does use an active cable which I assume arbitrates connections preventing any electrical damage. USB-C does not require active cables. I assume one of three things could happens. Nothing at all An error "don't do this" or something like that A connection is established with one host submitting as a device to the other host. (seems ...


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