Questions tagged [rs232]
For questions regarding the RS232 serial interface standard - its control and usage.
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Why did Linux standardise on RTS/CTS flow control for serial ports
I've recently been working out how best to wire up a serial cable for a vintage plotter, and it's thrown me down the rabbit hole of RS-232.
As far as I can tell, many RS-232 devices which act as DTEs (...
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How to connect Elektronika BK-0010 to an RS-232 interface?
Does any one of you have an electronic diagram and description of connecting the RS-232 serial bus to the Lithuanian computer Elektronika BK-0010? I need a diagram of a device to make myself.
My ...
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What is the serial protocol commonly used over RS-232 (among other links) and where did it come from?
The RS-232 standard (and ITU V.24 and V.28, which as I understand it are basically the same thing) specifies connectors (DB-25), electrical characteristics (-15 to -5/-3 V for "mark," +3/+5 ...
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How can I install a driver for a digitizing tablet Genius HiSketch 1212 in a VMWare virtual machine running Windows 98SE? [duplicate]
I posted a question some time ago - How can I make use of a Genius HiSketch 1212 serial-port drawing tablet on a modern PC? - and I didn't found the solution, but the scenario now has changed. This is ...
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How can I connect a Psion Series 5 PDA to a 64-bit Windows PC?
I have inherited a Psion PDA Series 5, from 1997, along with a serial port RS232 cable, and power supply. It takes industry standard Compact Flash cards, which can be removed and used to transfer ...
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DOS serial printer formats
Assume a DOS machine with a serial cable, and a selection of one of Epson FX-80, HP LaserJet, IBM Proprinter. At the other end of the serial cable is a modern machine, e.g. running Linux. On the DOS ...
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9-pin vs 10-pin serial port ribbon cables
I'm (still) putting an old Pentium PC together. I just found that the connectors of my serial port's ribbon cable have one less hole than needed. The socket on the mainboard has 10 pins, but the 10th ...
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Why was RS-232 12V?
Is there a particular reason RS-232 uses 12V signals (well, sort of) rather than some (any?) other value?
It was formally defined in 1960, so that places it before the era of any standardized ICs like ...
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Advantage of RS-232 over 20mA current loop
According to https://en.wikipedia.org/wiki/VT52
Like other early DEC terminals, the VT50 series were equipped with both an RS-232 port as well as a 20mA current loop, an older serial standard used ...
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How can I send RS-232 serial data to a Tandy plotter reliably?
I recently rescued my Tandy CGP-115 plotter from the attic and had the idea to try and drive it from a modern machine.
I have a FTDI CHIPI-X10 RS-232 adapter and installed drivers on a MacBook.
I have ...
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What was the very first device to have an RS-232 serial port
I find the RS-232 standard fascinating as it's one of the standards in computing that's survived - and is still used - for well over 50 years. The only major development has been a change in voltage ...
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How to connect an HX-20 to a monitor via the RS232 port?
Using & Programming the Epson HX-20 Portable Computer by Eric Balkan has a tantalising passage on p. 172*:
T.L. Ronson of the HX-20 User's Group also notes that a monochrome monitor can be ...
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Early programmable calculators with RS-232
In the early seventies, companies like HP and Wang sold 'programmable desktop calculators' that were really personal computers in the time before what is usually thought of as the dawn of personal ...
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Parallel to serial conversion
Two very common connectors used in the eighties were the Centronics parallel port (particularly used for printers) and the RS-232 serial port (particularly used for mice and modems).
Suppose you have ...
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Did terminals (e.g. VT100) require a terminal driver on the host computer?
I'm wondering if terminals (like, e.g. the VT100) required the installation of a driver on the host system in order to work with that host?
I looked at the documentation of the VT102, and there is ...
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Basic test for a RS232 serial terminal
I have a serial terminal that is not working. It's a VT525 using an external monitor (of course) and PS/2 PC keyboard. The self-test passes fine; setup works fine. I can echo characters when local ...
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Cartridge modems - was the Vic-20 a special case?
'The Home Computer Wars' has this to say about the development of the cartridge modem for the Vic-20:
The size of the case was another problem. Most modems came in bulky rectangular boxes about 10 ...
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Serial Receipt Printer Garbage
I connected a vintage serial matrix receipt printer (Datamega DPN-233) via FTDI to my MacBook's USB.
It performs its own self-test without problems, prints an example and the RS 232 configuration (...
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9-pin port for both RS-232 and Atari joystick?
A 9-pin RS-232 serial port looks superficially quite similar to the Atari joystick port. I don't suppose you could just plug a joystick into a serial port and have it work, but suppose you took this ...
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RS232 Tape Recorder Emulator?
I need to interface between an older system that uses an RS232 port for reading/writing to a tape and a more modern computer that can manipulate the data and send it back. Is there a software+hardware ...
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DECNet physical connector
DECNet was a network system for DEC computers, introduced in the mid to late seventies. What physical connector did it use? Was it possible to connect to such a network using just an RS-232 serial ...
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Hercules to COM<->USB adapter - is it possible?
I have a 486 (also another 286 mainboard) with a Hercules card, the plug is the same as RS-232. Is it possible to connect the output with serial port USB adapter and simulate Hercules-compatible ...
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Creating a 'bridge' between a serial port and a Telnet session in Windows 98?
I maintain an older Pentium III running Windows 98 as part of my collection of vintage machines. I named the box "Bridgette" because it basically is used to bridge my older machines into the modern ...
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Examples of usage of secondary channel on 25-pin RS232 serial port
The RS-232 standard allows a secondary channel on a 25-pin connector. Are there any examples where this secondary channel is actually used, in computers resp. devices connected via the serial port? ...
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Does the 25-pin IBM PS/1 serial port connector contain two serial ports?
I got my hands on an IBM PS/1 computer and it provides a 25-pin serial port connector. Whith the help of an adapter I can get a 9-pin serial port on COM1 and transfer data that way. I would like to ...
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How do serial (user port) adapters achieve speeds above 1200bps in C64?
The information I have states that the userport' serial speed is about 1200bps, but there are some carts going up to 9600bps.
I would imagine that the 1200 is the limit, so I'm wondering how is the ...
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