Questions tagged [db9]

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DB9 male or female Connector in Board

In my design I am using RS232 with DB9 connector in my PCB. idea is to log the data in PC and for programming via serial. Which connector I need to use in my board , it is male DB9 or female DB9. Q1) ...
4Mhz Crystal's user avatar
4 votes
2 answers
51k views

How do I do the 6 pin RJ11 to RS232 female serial adapter wiring?

I'm new to wiring and I have this RJ11 to DB9 RS232 adapter, and I'm not sure how to correctly insert the RJ11 wires into the DB9 female end. http://www.blackbox.com/Store/Detail.aspx/DB9-RJ-11-...
Jeremiah Malina's user avatar
3 votes
3 answers
6k views

Can I connect a "J1708" port to my computer?

This question is related to another question I posted here on the new Reverse Engineering site. I'm working with a small public transit agency on a neat open-source project that will help us to offer ...
drewbug's user avatar
  • 133
3 votes
1 answer
346 views

Capacitors for MAX232

I want to use this chip (ST3232CDR) as an RS232 transceiver. The problem is that I want to power the chip using 2 levels of voltage (3.3V and 5.0V) using a simple jumper, but in the datasheet (http://...
A. Kier's user avatar
  • 77
3 votes
0 answers
783 views

RS232 using a MAX3232 chip problems [closed]

I am trying to use RS232 to TTL convertor much like this: https://www.amazon.com/MAX3232-Female-Serial-Converter-Module/dp/B00BXX2OU2 I am not sure if the chip is authentic MAXIM or some knock off. ...
Greg S's user avatar
  • 39
2 votes
5 answers
11k views

Questions about wires in a DB9 cable

I stripped a DB9 extension cable which I will use to connect to a DB9 connector on one end and an RJ45 on another. I need to make connections to pin 2, 3, and 5 on the DB9 side. When I stripped the ...
200ok404notfound's user avatar
2 votes
1 answer
235 views

Is there any standard which defines that a particular connector or header on PCB has to be male or female?

Is there any standard which defines that connector (DB9, DB25, USB or header) type has to be MALE or FEMALE while choosing one to use on circuit board? I am designing a microcontroller circuit board ...
Osaid's user avatar
  • 569
2 votes
1 answer
548 views

How can I use a serial port to listen to if a toggle is switched?

Using a PC and writing some software I want to detect if a user toggles a small electric switch with as little external hardware as possible. I was thinking that maybe I could use a USB to serial ...
Andy's user avatar
  • 265
2 votes
2 answers
6k views

CAN bus DB9 pinout standards

There are two standards for DB9 pinouts when it comes to CAN bus. This seems to be the industrial version. I've seen it in PLCs and VFDs. 7 - CAN-H 2 - CAN-L 3 - GND 6 - GND 9 - VBAT This seems to ...
vini_i's user avatar
  • 7,108
2 votes
2 answers
4k views

What could be the reason for this RS422 wiring?

I usually follow the following wiring scheme for RS422 wiring: As seen above R+ to T+; R- to T-; T+ to R+ and T- to R-. So for each point to point wire R and T coupled but the signes are same i.e + ...
floppy380's user avatar
  • 1,845
2 votes
2 answers
2k views

Is my SparkFun RS232 Shifter SMD faulty?

Product Link I am connecting this to an Arduino. (once Arduino programmed I removed the USB connector as it shares the serial comms with Pin0&1) RS232<->Arduino VCC <-> 5V GND <-> GND ...
Richard Freedman's user avatar
2 votes
2 answers
4k views

Voltage Conversion In PC Serial (DB9) Port

First of all, I am not even a noob when it comes to electronics. I don't even know what I am asking is possible but here it comes. At first glance, it may seem as an computer-related question, but ...
SercioSoydanov's user avatar
1 vote
3 answers
4k views

Changing DB9 Gender: Crossover or Straight? [closed]

I have a USB-DB9(Male) that needs to communicate with a device that has a DB9(Male) port. Do I connect both DB9(male) ports together using a null modem (crossover) cable or a straight through cable? ...
Nyxynyx's user avatar
  • 1,151
1 vote
3 answers
1k views

PS/2 keyboard with RS232 (DB9) workstation port

I'm currently awaiting for dispatch/delivery of a 1995 PS/2 Model M keyboard w/attached flat cable but a missing PS/2 plug It seems those flat cables were not very sturdy. (Yes, I checked the model ...
Groucho's user avatar
  • 53
1 vote
5 answers
874 views

How should I mount DB9 Connector?

How do I mount that DB9 Connector on this GPB? Any tricks?
MaNyYaCk's user avatar
  • 1,468
1 vote
1 answer
971 views

Does this wiring pattern for a DB9 cable exist as a standard cable?

I have a scientific instrument that uses a DB9 cable to connect to the standard RS232 port on a computer for communication. I've deconstructed one of the cables as I needed to make another one but I ...
test's user avatar
  • 121
1 vote
3 answers
1k views

Db9 shield connection? in plastic hood!

at my work there are a network of identical devices each of which control some 50 location-guidance light units. These devices or controllers are all linked together and then to a main server/computer ...
Peter Kovacs's user avatar
1 vote
2 answers
4k views

How to Make DB9 F/F serial RS232 mini gender changer?

I want to connect My "USB to RS232(Male end)" to my NanoVolt Meter having RS232 male port. To make both communicate i need to make DB9 F/F serial RS232 mini gender changer. Any Circuit or suggestion ...
Bhavesh Gohel's user avatar
1 vote
1 answer
59 views

Two devices on Y 9pin Serial cable to 25pin printer input - Data Corruption

I have't been able to find a solution, and was hoping for some clarity. I have 2 machines (one is a bill counter, one is a coin sorter) that both support printing over DB9 serial connection, and one ...
CaffeineZombie's user avatar
1 vote
2 answers
4k views

Straight vs Null Modem Serial cable confusion

I have a cable having a DB 9 male at one end and a female at another end. I will be using this cable to connect BeagleBoard Xm ver C1 to the serial port of my PC. I understand the pins with respect ...
gpuguy's user avatar
  • 1,638
1 vote
1 answer
89 views

CAN communication on tms320f28377s using usbToCan driver with db9 connector

I am using launchpad xl f28377s. It has a CAN transceiver which is intagreted. How can I connect this card to usbToCAN ixxat driver using db9 connector ? Thanks, Regards.
Furkan Yumbul's user avatar
1 vote
1 answer
9k views

Pin assignment on rj45 when using rs232

I am having a problem creating a cable to connect with two devices. The first devisce is an Intellivue MP70 that I want to connect to the RS232 port using an RJ45 end. On the other side there should ...
FewWords's user avatar
  • 113
0 votes
3 answers
3k views

Is it common practice to connect power supply to a DB9?

I got a project where many sensors which uses CAN were connected to a DB9. And sensor power (24V and GND) too. I want to connect the DB9 terminal to power however how can I do it in a safe way? If I ...
pb772's user avatar
  • 133
0 votes
4 answers
6k views

What is a 3 wire type cross linked serial cable?

I'm trying to use a controller which uses Serial communication with the PC. The documentation says I need to get a 3 wire type cross link serial cable. Is this a null modem cable? The following ...
Joshua's user avatar
  • 235
0 votes
3 answers
2k views

How to mount a DB-9 adapter to an enclosure

I have a DB-9 connector that needs to be mounted to an electronics enclosure. This hole for the DB-9 connector will be manually cut out. Question: How can the DB-9 connector be secured to the ...
Nyxynyx's user avatar
  • 1,151
0 votes
1 answer
542 views

Extra 2 DB9 pins connection

Many DB9 symbols have 2 additional pins other than the 9 signal and GND pins that they are known for. How and to what are these 2 pins connected ? Pins 10 and 11. Is it connected to chassis ground or ...
Board-Man's user avatar
  • 1,929
0 votes
2 answers
746 views

12V/5A power through DB9

Required to use a DB9 connector to pass DC to unit requiring 12V/5A supply. An easy way to do that is using a DB-9 to Terminal Block adapter. But most DB-9 to TB adapters I see have 3 A or less ...
eecs's user avatar
  • 165
0 votes
2 answers
3k views

Making a DB9 Cable

I need to make a DB9 cable due to the need to have a custom pin out. I will get a few StarTech.com DB9 Serial Male D-Sub Crimp Connector (C9PCM) to get started. What crimping tool do I need to ...
Nyxynyx's user avatar
  • 1,151
0 votes
1 answer
279 views

Using DB9 connectors for LVDS signals

Has anyone utilized 9-pin DB9 connectors for driving and receiving LVDS signals? I wanted to use Micro-D connectors on a board I am developing but they take too long to get. Since DB9 connectors are ...
Daniel Lin's user avatar
0 votes
1 answer
643 views

Serial DB9 to Serial 3.5mm over HDMI cabling

Good afternoon everyone. I am trying to control a Samsung TV via Serial from a remote processor and I am trying to use spare installed HDMI cabling to do it. Samsung does not have an open API for IP ...
eto.ttnflt's user avatar
0 votes
1 answer
38 views

What do the different LED lights indicate on a DB-9 tester and what can I infer from them? [closed]

I have a machine with an RS-232 port. When I power ON the machine and connect the DB-9 tester all the machine's troubleshooting guide requires is to check if the RTS light is green. I see there are ...
Sachin 's user avatar
0 votes
3 answers
522 views

Help wiring a Raspberry Pi and odd DB9 connection

I need to send a signal from a Raspberry Pi 4 to a PC running software that listens on a COM port and I'm having some trouble understanding the necessary wiring. Here is the documentation I have for ...
Mike Buss's user avatar
  • 103
0 votes
1 answer
367 views

RS485 Pinout when using PyModbus

I am trying to control a RS-485 RTU device (Love 16C-3) using a Python script (pymodbus library) that runs on a Windows 10 PC. The hardware is connected to the ...
Nyxynyx's user avatar
  • 1,151
0 votes
0 answers
202 views

Can0 return no data, but with no error

I'm actually trying to get data from a CAN on vehicle connected by DB9 on my raspberry. The DB9 provides also energy to the raspberry (here the material that i'm using). I've followed every of these ...
wajisan's user avatar
0 votes
0 answers
367 views

How to wire RJ12 to db9f modular adaptor?

I have a RJ-12 to DB9f modular adapter. There are 6 wires that come out of the adaptor (White, Black, Red, Green, Yellow Blue) - these, as I gather from pin out diagrams, correspond to the 6 jacks of ...
user8244's user avatar
  • 183
-1 votes
2 answers
1k views

3.5mm to DB9 connector (differences) [closed]

I have 2 different type of connectors of 3.5mm to DB9 that I use to send RS232 commands from device to a screen. The 3.5mm is attached to the device on the serial port and the DB9 to a serial cable ...
Zaid's user avatar
  • 11
-1 votes
1 answer
106 views

Doubts about Max232 IC chip

I have a Max 202 Ic and Max 232 Ic I currently want to make a USB to RS232 Serial Db9 converter i have the db9 male port, a max 232 and max 202 , usb female port and bunch of other passive components ....
swagdevotee008's user avatar
-2 votes
2 answers
4k views

What's the difference between a null modem cable and a gender changer? [closed]

Please ignore this question. It doesn't address the problem I was trying to solve (XY problem) and my edits have been reverted. Because it has answers, I can't delete it. It should be closed as off-...
Agi Hammerthief's user avatar