making USB cables

Started by divx dude in sci.electronics.design6 years ago 10 replies
USB

going to run some cat5 cable to use for USB cams.. how many USB can i make from the 8 wires? USB 1.0 used only 2 wires for signal and 2 for...

going to run some cat5 cable to use for USB cams.. how many USB can i make from the 8 wires? USB 1.0 used only 2 wires for signal and 2 for power but USB 2.0 apparently uses the connector chassis for a 5th connection. can that be shared? say for a double or triple USB gang? or must be completely isolated such that only two USB can be created with 8 wires. 3+3+2(power)


PIC16F1454/5/9 USB example

Started by Sonnich Jensen in sci.electronics.design2 years ago 3 replies
USB

Hi all I have been looking for any example for how to use USB - for the PIC16F1454/5/9 USB example - even just transferring a single byte....

Hi all I have been looking for any example for how to use USB - for the PIC16F1454/5/9 USB example - even just transferring a single byte. Can anyone point me to an example: 1) example of pic code/usb functionality 2) USB driver for PS (some ini file), what to put there and how to use it I am used to communicating to com port (usb act the same way), but the driver thing is new to me...


USB PORTS on the motherboard WORST INVENTION EVER.

Started by Skybuck Flying in sci.electronics.design5 years ago 89 replies

When USB was invented I thought what I stupid idea. Who the fok powers devices via a communication cable ?! Only a NUTCASE would have...

When USB was invented I thought what I stupid idea. Who the fok powers devices via a communication cable ?! Only a NUTCASE would have thought of that ?! And my feeling has become a reality. THE USB PORTS ARE DESIGNED SO RETARDLY that it is actually possible to connect the USB PLUGS wrongly very easily !!! As a result of the power flowing through the USB cables this will FRY the ...


most universal USB connector

Started by John Larkin in sci.electronics.design6 years ago 77 replies

I'm designing a series of small boxes that will use a USB connector for power, and some will go on to implement the a USB interface...

I'm designing a series of small boxes that will use a USB connector for power, and some will go on to implement the a USB interface for control. So, what's the most common USB connector, to put on the PCB of a slave device? Mini-B? Micro-A or Micro-B or Micro-AB? I think there a new european standard for using USB to charge cell phones. Anybody know what connector that is? -- ...


USB serial follies

Started by John Larkin in sci.electronics.design5 years ago 21 replies

I have a commercial usb-serial dongle that uses the Prolific chip. If I plug it into one USB connector on my PC, it comes up as COM4...

I have a commercial usb-serial dongle that uses the Prolific chip. If I plug it into one USB connector on my PC, it comes up as COM4 and works. If I plug it into a different USB connector, XP tells me the driver is bad and has to be reinstalled. If I plug it into my USB hub, it shows up (in device manager) as COM D and says that something's wrong. Makes no sense to me. Any ideas? ...


LPC1768 USB hangup

Started by John Larkin in sci.electronics.design5 years ago 22 replies
USB

We built a little picosecond pulse generator box with a USB interface. The USB is directly into an LPC1768 NXP ARM chip, and we're using...

We built a little picosecond pulse generator box with a USB interface. The USB is directly into an LPC1768 NXP ARM chip, and we're using the USB stack and inf file that Code Red provided. It enumerates as a serial port. It's "unsupported", which means it's *really* unsupported. Under Windows XP, there's a small glitch. I can plug/unplug the USB cable, and it always makes all the proper...


USB switch problem

Started by Power boy in sci.electronics.design8 years ago 1 reply
USB

Hi, All: I have a selfpowered spectrometer which needs 250mA from a USB 2.0 port, I also have a mcu to control everything including talking...

Hi, All: I have a selfpowered spectrometer which needs 250mA from a USB 2.0 port, I also have a mcu to control everything including talking to the spectrometer. I want to make life easier thus I use this following option: a usb 2.0 switch with pin rating +/-40mA working as a usb hub. Can I do that? I think the 250mA is from the power pins of USB port not from the D+/D-. P.S. Here is my...


Micro USB Power cable -- which are the power pins

Started by Anonymous in sci.electronics.design5 years ago 13 replies
USB

If this is a slightly off topic query, I apologize. Could some electronics guru please help ? I am not at all familiar with the micro USB...

If this is a slightly off topic query, I apologize. Could some electronics guru please help ? I am not at all familiar with the micro USB power cable, and here are some questions: 1. As I understand it, the USB cable has a micro USB connector on one end, and a regular USB connector on the other. The power is fed in via the regular USB connector, and the micro USB connector plu...


USB Withstanding Voltages

Started by Tim Wescott in sci.electronics.design4 years ago 13 replies
USB

I should look this up. But I'm lazy, and I know who to trust on this group. I'm writing a set of instructions for a board that has two...

I should look this up. But I'm lazy, and I know who to trust on this group. I'm writing a set of instructions for a board that has two physicaly identical connectors, one with RS-232 signals on it, and one with USB. I know that a user can plug USB into the RS-232 side with impunity -- what happens when a USB port gets -7V applied to it's D- input? Donkey shorn. -- Tim Wescot...


isolated USB

Started by Martin Riddle in sci.electronics.design8 years ago 4 replies
USB

So far I found a few, and The keterex box, which is about $100. Are there any others? Maybe a cable with a lump? This is a USB to USB isolator...

So far I found a few, and The keterex box, which is about $100. Are there any others? Maybe a cable with a lump? This is a USB to USB isolator I'm looking for. Thanks


USB power supply for charging

Started by Mike V in sci.electronics.design9 years ago 8 replies
USB

I've been asked to add 2 USB power outputs to a product to allow ipods, phones, cameras etc to be charged. Sounds easy. USB specs 5V, 500mA...

I've been asked to add 2 USB power outputs to a product to allow ipods, phones, cameras etc to be charged. Sounds easy. USB specs 5V, 500mA max per output. So the obvious solution is a 5V 1A regulator driving 2 USB connectors in parallel. But is it that easy? Do USB peripherals need to talk to the power supply? Do the outputs need to be independant:? What else don't I know? I'm getting ...


USB protocol, couple of questions on low level stuff...

Started by Brane2 in sci.electronics.design4 years ago 2 replies
USB

I am plowing my way through available USB1/2 literature, but I still have a few holes on actual implementation. 1. if everything on USB has to...

I am plowing my way through available USB1/2 literature, but I still have a few holes on actual implementation. 1. if everything on USB has to be carefully timed, how does USB hub cope with the consequences of bit-stuffing as part of NRZI coding ? I mean, when doing IN transaction, USB HUB can not know in advance how much bits will some packet actually have on wire as that will depend on ho...


Embedded USB-to-serial converter

Started by Peabody in sci.electronics.design6 months ago 22 replies

I could use some help thinking through what options I may have, if any, for embedding a CP2102 USB-to-serial converter into a MSP430...

I could use some help thinking through what options I may have, if any, for embedding a CP2102 USB-to-serial converter into a MSP430 microprocessor project, so that updating the flash could be done with just a USB cable. The processor would be a MSP430G2231. This function is built into Arduino boards, which have more powerful processors with dedicated pins for all the USB and serial stu...


PIC24 USB suspend current

Started by Sylvia Else in sci.electronics.design3 years ago 1 reply

I've posted this on a Microchip forum, but I thought I'd see whether anyone here knows the answer. I'm using a PIC24FJ64GB004 family...

I've posted this on a Microchip forum, but I thought I'd see whether anyone here knows the answer. I'm using a PIC24FJ64GB004 family MCU. Is there any way of getting this MCU to consume no more than its maximum allowed 2.5mA when in USB suspend mode? If I leave the USB module off, but set the system clock to the lowest value it would be permitted were the USB module in use (16MHz), ...


Rugged USB card?

Started by Joerg in sci.electronics.design6 years ago 49 replies
USB

Hi Guys, Does anyone know of a super-rugged USB card with four or more USB downstream slots? PCI-e or PCI would be nice. External hub not so...

Hi Guys, Does anyone know of a super-rugged USB card with four or more USB downstream slots? PCI-e or PCI would be nice. External hub not so much, but would be ok if nothing else is available. Main drawbacks of literally every card I've seen: USB tied into board but not into the PC chassis. No common mode chokes. Both of this is causing ESD failures galore. Price is not too important ...


Formatting Corrupted WD HDD

Started by David King in sci.electronics.design3 years ago 19 replies
USB

Please excuse me for restarting this thread, but the other was quite long and there has been a slight delay from my side due to...

Please excuse me for restarting this thread, but the other was quite long and there has been a slight delay from my side due to personal circumstances. I have done as Jan suggested, which is to connect the HDD to my Linux machine and enter DMESG. This is what shows: [ 66.672060] usb 1-1: new high-speed USB device number 2 using ehci-pci [ 67.100075] usb 1-1: new high-speed USB d...


Reverse IDE to USB adaptor?

Started by _ in sci.electronics.design9 years ago 25 replies

Toying with the idea of replacing an HD with a usb stick, to reduce power usage, weight, heat, size, etcetera. There are lost of adaptors...

Toying with the idea of replacing an HD with a usb stick, to reduce power usage, weight, heat, size, etcetera. There are lost of adaptors that let you plug a drive into a usb port; is there an adaptor that does the reverse? The board in question (Series 1 Tivo) has no USB port, just an IDE connector.


Why put a type-A USB connector on a peripheral device?

Started by Peabody in sci.electronics.design7 months ago 17 replies

I've been looking at USB-to-UART adapters, and find that a lot of them have type-A USB connectors. And I'm curious why that would be done...

I've been looking at USB-to-UART adapters, and find that a lot of them have type-A USB connectors. And I'm curious why that would be done instead of a mini or micro USB connector. Assuming the other end of the cable is plugged into a computer, then that would require a tyoe-A to type-A cable, and I don't remember ever owning one of those. What would be a use case where using a type-A ...


USB Power

Started by John Devereux in sci.electronics.design9 years ago 11 replies
USB

Hi, It seems the specification allows USB devices to draw up to 100mA (for a "low power" port) and 500mA (high power port). Does anyone...

Hi, It seems the specification allows USB devices to draw up to 100mA (for a "low power" port) and 500mA (high power port). Does anyone have any idea of the incidence of high power ports? Especially on laptops. For a design with USB control, I am trying to decide if it is worth including an option to take all the power from USB, rather than a wall-wart type adapter. It would be grea...


USB CDC device works on laptop, but not on WinBook tablet

Started by P E Schoen in sci.electronics.design2 years ago 14 replies

I have a USB device that I designed several years ago, using the Microchip PIC18F2550, and it has worked mostly OK on various laptops. It has...

I have a USB device that I designed several years ago, using the Microchip PIC18F2550, and it has worked mostly OK on various laptops. It has four DC-DC converters driven by the USB 5V power and it is configured for the maximum 500 mA current draw. The actual current is 350 mA. The 5V USB supply connects to a 47 uF 16V aluminum electrolytic and a 1 uF 16V MLC capacitor. The 5V logic supp...