Null rs 232c to usb data cable

And just in time for Thunderbolt 3 and 4. Where transfer speeds can reach as high as 40Gbps. Even having a 3 prong laptop power supply is no guarantee your laptop itself will be grounded.

I measure no continuity from the negative output to the power supply ground. Seems like a handy thing to have in a toolbox, just in case. Apple computers with Firewire had the ability to boot as an external drive and network over Firewire, both of which should definitely have been standard features in USB. Better yet, my iMac has the ability to act as an external display over displayport — which should be a feature in HDMI-connected AIOs and botebooks, imo. Have you tried using your iMac as a DisplayPort-display?

It a hardly-supported mode and only works with a handful of Apple-computer on the other end of the cable. It was intended to allow you to make use of the very nice display in an iMac once the iMac itself was getting old. Given that my 10 year old imac is Only now nearing replacement but still has more poke than my new windows laptop , that was probably over engineering….

FireWire was peer to peer. So if at least one of the two ports being connected together with a typical e. Thanks to this, USB has been as useful as it was. Nowadays it is becoming more simplified then ever, but back in the days…. You can make a fairly nice one of these from a couple of cheap serial adapters and jumper wires, you probably already have everything you need just lying around the junk pile. No blocked ports, no firewall issues etc.

Oh yeah dialup-bbs-tnc-gateway to internet you appreciate the value of a fast and ready null-modem in best form available, wars get won that way and shiat, ]:o great project…. I believe they route the data through the network stack vs this design being two serial ports. Both would have advantages in certain applications. If you really want to transfer data this way you are much better served by two USB to Ethernet adapters and a cat5 cable, also solves the electrical isolation issues nicely.

They bypassed the transformer and connect directly to the chips. The chip blew up when I move it directly to the USB port and the higher than expected voltage closer to 5V blew up the chip. If only they actually used a zener and diode. Not to say that the tolerances and proper loading of the zener diode would be done properly either. That being said, a pass transistor can be had for 3 cents, and a real requlator for a dime so yeah, you should probably use better regulation in a real design.

Well the thing died after becoming so hot the plastic case started to droop. I did it because I had a specific application where I needed serial. Ahh, the joys of asynchronous serial communications. So many ways for it not to work. I used to have a box full of null modem adapters for different applications, plus some that had pin breakouts for custom wirings. No support for Mac OS, no support for Linux, etc.

Something I never had to deal with. Reminds me of the time I tried to decipher the one-wire serial signal of Sony Ericsson walkman phones that were used for complex add-on devices, from about 15 to 20 years ago.

Flow control should be implicit too. There is something to be said for the potential to moot baud rate and word format issues. You could use two chips that implement the CDC protocol that ignores the baud rate set on the USB side, but use a standard and very high baud rate over the isolation barrier.

That would mean using a microcontroller and a software implementation of CDC. Very doable, but just buying the Cypress Semi chips is vastly more convenient. We had side-by side machines on each network with something like this in between as the only link. The files moved over the serial link via an old-school serial file transfer program running on each machine. And, indeed, there are still Linux and FreeBSD drivers that can be used with those chips to make point-to-point network interfaces.

I went with CDC for this use because I specifically needed them to be serial ports for my application. So yeah, good idea. I would be tempted to have the two sides connect via ethernet so files can be transferred faster. Also appreciate the comments around isolation. Probably better than my strategy of just using an old cheap laptop :. Worst case you can do a bit of piping and use cat. Worked as advertised, but 1 gig of data moves really slow over USB 1. Not many people had home networks then, and wifi was pretty exotic and still as slow as USB, so I thought I was pretty slick.

But I would have thought the shield on the USB cable would have balanced that before the internal pins connected, no? Reading between the lines, it sounds like you used TP Ethernet. The magnetics that are on each end of the TP line offer galvanic isolation, so you were good.

System of Measurement. End Type. Connection Type. End Shape. Shield Type. Cord OD. Cord Length. USB Connection Type. USB Standard. Housing Material. View catalog pages 3. Send Cancel. How can we improve? D-Sub Cords. Length, ft. Create a Support Ticket.

When you need immediate help, call us! You'll be connected with the nearest support center. See Your Options. Learn More. If you have an account on tripplite. If you have questions about any Tripp Lite product or service, please contact us. We're always glad to help! It was later adopted by the personal computer industry so PCs could connect to modems, peripherals and data acquisition devices such as lab test equipment, GPS receivers and point of sale terminals.

By specifying the voltage, signaling, pin wiring and control data between a host device and a peripheral, the RS standard ensured that devices from different manufacturers could communicate with each other. A serial port was standard on personal computers until the late s, when it was mostly replaced by the Universal Serial Bus USB.

It is still common on legacy devices that use serial communications for data capture, configuration and control. What is the difference between RS and RS? It specified the same DB25 connector as the original RS standard. RS is also found on professional video broadcasting equipment. The RS standard was published in and is substantially similar to the earlier RS standard.

The big difference is support for multiple transmitters and receivers, allowing devices connected on an RS network to "talk amongst themselves" in half-duplex mode over inexpensive twisted pair cabling. RS describes the electrical characteristics of the drivers and receivers but does not specify a communication protocol.

RS has been widely used as the physical layer for standard and proprietary protocols in industrial control systems, including Modbus and Allen Bradley DH Point-to-Point — a connection between two devices in which bits are transmitted sequentially, one at a time. Multidrop — a type of bus in which multiple devices are connected at the same time. Through a process of arbitration, one device sends and other devices listen for data packets intended for them. Unbalanced vs.

Balanced — A balanced transmission requires three wires, two signal wires and a ground. Both signal wires carry the same signal, with one signal the inverse of the other this is referred to as Differential Signaling.

In an unbalanced transmission, the signal is carried on one conductor and a second conductor is used for ground. The D-Subminiature or D-Sub connector is named for the D-shaped metal shield that protects the pins and ensures the correct orientation.

First introduced by Cannon in , the D-sub form factor was adopted for the RS serial communications standard. The pin D-Sub was the only connector specified in the original RS standard. The 25 pins handled the data transmission, control signaling and grounding required by the relatively simple applications and devices of the time. Many serial devices did not implement all 20 control signals in the original RS specification. Smaller, simplified connectors with fewer pins, like the DB9, quickly emerged.

It was also used as a serial connector for game controllers e. The RS standard defines voltage levels for logical 1 and logical 0. Devices, such as computers and printers, use control signals to synchronize the transmitting and receiving of data. These signals indicate the status of Sender and Receiver ready, busy, transmitting and receiving and control the flow of data. For example, the signals supported by a DB9 connector are:. A standard serial port transmits at Kbps. This may be faster than the connected device can handle.

Using flow control RTS and CTS , the device can temporarily stop the flow of data from the computer so it can process the data in its buffer.

RS cables can be simple parallel wires or twisted pair up to 15 m 50 ft. For all serial communication, there is an inverse relationship between cable length and data transmission speed. At the maximum length of 15 meters 50 feet , an RS port will support a data rates up to 20 Kbps. Greater distances can be achieved with a slower data rate and shielded CATx cable see RJ45 serial adapters.

Computer peripherals such as printers have also adopted the USB interface or gone wireless. However, some network switches, routers and serial devices still use a serial interface, including lab equipment, barcode readers, industrial controllers and data gathering sensors.

When a host computer boots up, it assigns a port address to each device including any USB adapters connected to the bus and determines the type of data transfer the device wants to perform. Once the adapter is registered, it looks like a USB peripheral device to the host computer.