Questions tagged [max232]
Anything related to the MAX232 integrated circuit. The MAX232 IC is used to convert serial communication signals using TTL levels, such as those produced by UARTs ICs, from and to standard RS-232 line signals.
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PHD ULTRA syringe pump communicate with Arduino
I have a PHD ULTRA syringe pump from Harvard Apparatus. I want to establish communication between an Arduino and the syringe pump. The company provided me with a Python code, but Arduino does not ...
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Is it normal for a MAX232 chip to test positive for continuity between T1OUT and R1IN when powered?
I have noticed, on my MAX232 chip, that when the IC is powered, a continuity test between the T1OUT and R1IN pins tests positive. But not when it is not powered.
Is this normal?
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RS232 isolated communication via MAX3250
I have a two diffrent boards. One of the board is send the SoC and other things to Charger Board. While charging progress starts I want to isolate this to device because battery ground is isolated to ...
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Odd behavior using the MAX3323EEPE to translate RS232 output to TTL logic levels
simulate this circuit – Schematic created using CircuitLab
I am using the MAX3323EEPE Maxim IC in order to attempt to take RS-232 output from a peripheral and shift it down to TTL logic levels ...
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Configuring SPI circuit design for use in 485 transceiver for long range data transmission (50 meters plus)
So quickly getting out of things I have previously done in trying to send SPI controller signals across long ranges using either 18 AWG cable or based on all the recommendations we have been reading, ...
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MAX3232: Switch between RS-232 and TTL levels
Sorry in advance, electronics noob here!
I need to make a proof of concept to get some data out of third party system which handles both RS232 and TTL levels.
The computer/raspberry/arduino shall - I ...
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MAX232 IC does not convert to and form RS232 levels
I made a simple circuit to read data from RS232 lines and print data on different RS232 lines. This is the IC I am using: MAX3232EIDWG4. The IC fails to convert the CMOS to RS232 level logic.
I am ...
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RS-232 Crossover, and Protection against shorting two TXD lines
I'm in the process of designing a USB to RS-232 converter for communication with some existing boards, and I ran into two problems.
First Question
I need a way to programmatically reverse the TXD and ...
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Max232 to DB9 connection confusion
The picture shows standard connection between 8051 and DB-9 via MAX232. 14th pin is the translated output of the transmitted data by 8051, so this should be connected to the receiver pin of DB-9, ...
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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 ....
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MAX233 problem with receiving data
I need to make serial connection between regular PCs and a 3.3v TTL device, I using the Maxim 233 which has internal capacitors.
I have the PCs incoming TD connected to R1_IN and RD T1_OUT.
The ground ...
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Is it possible to use a MAX232 to convert 0 to 5V PWM to 0 to 12V PWM to input to a motor driver requiring 0 to 12V PWM logic?
I'd like to drive a 16kHz PWM signal at 0.5mA into the input of a motor driver expecting logic levels of 0V for LOW and 12V for HIGH, and expecting a PWM signal around this frequency. The PWM signal ...
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3.3V TTL to other formats and impedance matching [closed]
I am trying to convert a 3.3V 50 Ohm Impedance TTL Pulse-per-second into other formats (GPIB, USB, RS-232, etc.). I've found some format adapters/convertors like the MAX232, but I am either ...
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Ultrasonic dual transmitter-receiver circuit
I am building an ultrasonic flow sensor, based on piezoelectric actuators from cheap HR-SR04 modules. I need to measure the speed of sound back and forth. Schematic like this is good to send pulses:
...
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Interfacing stm32 with MAX232
I am interfacing MAX232 with STM32F030k6. I have very recently found out that Max3232 would be a better choice, because it works with 3,3 volt. But I am eager to know if UART reciever pin of the ...
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Why use 100E resistor in max232 ic in serial pins 13 and 14?
serial pin 13(RxD) use 100E -pin 13 to male connector pin 2(RxD),
serial pin 14(TxD) use 100E -pin 14 to male connector pin 3(TxD)
Why 100E used?
I have attached image and mention clearly for your ...
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why use of 1uf capacitors in max232 ic, why does not use 10uf capacitor in max232 ic.?
I have use 1uf capacitor in max232 circuit
c1=1uf (pin 1 and 3)
c2=1uf (pin 4 and 5)
c3=1uf (pin 2 and vcc)
c4=1uf (pin 6 and gnd)
c5=0.1uf (pin vcc and gnd)
why this type of values used?
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Less noisy version of max232
After (mentally) banging my head at the wall wondering why my own circuit is glitchy after the PC communicates with it, I read some posts, and noticed others had very similar problems. All because the ...
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Comparing MAX3232 vs MAX232 for line length
Which parameter in the datasheets of the line drivers MAX3232 and MAX232 can tell about the maximum length of the line for their correct operation if all else is same for the two circuits, that is ...
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Transmission from atmega32 to PC using max232 not working
Transmission from atmega32 to PC using max232 not working. When I checked the data from the Tx pin (in the realterm software) of atmega32 it was fine. But there was no output data from max232, when I ...
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Can I use 10\$\mu\$F caps in a MAX232?
this is just a quick and dirty question. I don't understand the purpose of the 1 \$\mu\$F caps in the MAX232 circuit. What do they do, exactly? Can they be skipped? Can they be swapped with 10 \$\mu\$...
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MAX232 vs TRS202EC Line Drivers
I have used MAX232 as UART serial line driver using 5V power supply. Now I have come across TRS202 chip in a circuit. It also run with 5V power supply. Does this chip has some special difference or is ...
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RS-232 interface chip problem - why is the voltage level so wrong?
1. What I want to do:
I have a PCB with an AVR microcontroller (ATmega16U4) on it. I want the microcontroller to communicate with my computer through an RS-232 cable.
2. What I did:
I added an ...
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Can a MAX232 IC be used for RS-232C standard?
I have a GT01 Panasonic LCD which it's interface is RS-232C.
I have read that the difference between RS-232 and RS-232C is their voltage level which it's ±5 V in RS232C.
Can I use a MAX232 IC to ...
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max232 charge pump problem
I have a problem with my MAX232 chip and can't find the solution. The schematic of the chip is in the attachment. The chip is soldered on to a PCB.
I've checked all the connections, the supply ...
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Can I use a MAX232 to communicate between a PIC and a Raspberry Pi?
I would like to send serial data at 9600 baud between a PIC and a Raspberry Pi.
Both circuits are powered by a 5V wall charger. The distance shouldn't exceed 15cm. They don't currently share a ...
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Why all the other ultrasonic sensors are getting triggered when only one so actually triggered?
I have an ultrasonic sensor, HC SR04, connected to the atmega 8 controller along with an LED for the indication purpose.
Let me discribe about my project with some anology.
Say I have 20 rooms( ...
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Capacitors in MAX 232
Out of curiosity, can I replace the electrolytic capacitors in the circuit with non-polar ceramic capacitors? Will I get the shifting in level?
MAX232 datasheet: LINK
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Connect unused inputs/outputs on RS232 line driver/receiver Chip
What is the safest (and reliable) way to deal with unused input/output pins of serial comm. chips like MAX232, ST3232, etc..
So far i'm familiar with these three options:
Input and Output Not ...
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What TVS diode should use for MAX232 and MAX485, whether uni or Bi-directional?
What TVS diode should use for MAX232 and MAX485 driver, whether to use unidirectional or Bi-directional TVS diode? if any reason why?
Also, Please tell me what clamping and standoff voltage to use.
...
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Raspberry Pi ver 2.0 UART connection with PC and Xbee
I am trying to connect Raspberry Pi ver 2 with my PC using UART.
Connection of my board is
Raspi Tx -> Rx RS232toUSB PC
Raspi Rx -> Tx RS232toUSB PC
Raspi GND -> GND PC
Problem I am facing ...
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Circuit guidance to output -14V from 12V supply
Good day to all potential problem solvers!
I would love some assistance with a particularly tricky circuit. I have an Arduino board and a particularly elusive green/black 128x128 GLCD screen I came ...
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Voltage level too low for MAX232
I'm trying to connect TI's MAX232 to my Arduino so that I can communicate with my PC. I have connected it exactly as the picture shows:
Tx/Rx are not connected because I just wanted to see if I can ...
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May I use CD4066 instead max 232, to convert rs232 UART(USART) level
As in the title, Is it possible to use the CD4066 as level driver through RS232 and TTL(USART)?
If it's possible how this work.
Thanks.
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MAX232 circuit not working
I am designing a circuit using a MAX232. I have connected Tx and Rx of the MCU to the 11th &...
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LEDs on 3.3V serial and sd card select lines
How would i go about connecting indicator LEDs to the serial lines from my MCU(a Parallax Propeller) to a MAX3232 and the chip select line for a SD card? I want the LEDs to light up when the lines are ...
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Electronic switch with negative and positive voltage
I want to use a micro-controller to send data through a max232 that will convert the 0v/5v signals into -12/+12v signals. The problem with this IC is that when there's no signal, it sends a +12v ...
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Flashing Hex File to AT89C51
I have a USB to Serial breakout which has CP2102 and MAX232 chips on it. I wrote a program in Keil and generated the Hex File. How do I flash this hex file onto the AT89C51 (which is also another ...
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Max232 TX working but Rx not working
I have two PCB which has PIC32 as a Controller and two serial port. I tested the 1st PCB and serial port was working fine. I was able to send and receive data. But ...
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xmega serial communication using MAX3232
Hi I am trying to talk to send a character to the PC using the xmega128a1 and the MAX3232 USART to Serial converter chip. Here is my setup and "send char" function below:
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RX/TX LED for MAX232
I want to use two LEDs to show send and receive on my max232 RS232 to TTL (5v) converter. I have seen this method as the most conventional way to power an LED for max232:
I tested it and the LED ...
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How does the MAX232 double the voltage?
MAX232 Datasheet
Hi, I am currently a student so bear with me please!
I'm currently using a powering the MAX232 with 5V DC, and when I measure from VCC to lets say, pin 3, I am getting a voltage ...
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UART - getting gibberish data from MAX232 with PIC16F877A mcu
I have created a serial communication between my laptop and 16F877A mcu. I have used MAX232EPE IC as level converter also. According to my code If I send a character to the MCU, MCU will return a ...
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How to program an ATMega328 using a Serial Port without using programmers such as USBasp
I am currently learning electronics. I recently bought an ATMega328 and an USBasp programmer to begin my learning. But I couldn't use the USBasp to program my chip. So I researched on other ways to ...
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Questions about an atmega32 serial-bus to RS232 with converter and different logic levels
I have an atmega32 and a FUM DCF-U atomic clock (signal receiver and decoder) of HKW-elektronik. The µ-controller works with 5V and the module on 3.3V.
I have to build a converter, because the µ-...
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Max232 giving incorrect values at pins
Background:
I'm trying to connect a Compact Logix PLC -> MAX232CPE Maxium chip -> arduino.
Currently my PLC does communicate modbus RS232 with a request for data from the arduino. I can see this by ...
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Do we need MAX232/ADM3203 for UART communication with PIC32MX795F512L [closed]
I am trying to communicate UART with PIC32MX795F512L. I am really confused with this thing that we should use MAX232/ADM3202 or pins will directly commnicate. Because in some microcontroller, it is ...
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PIC MCU to PC Serial Communication Problem
I was just trying to send continuous stream of letter 'G' from my PIC MCU (PIC18F452) to my laptop.
Here is my assembly code that i am using :
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Additional TX and RX pins for FT232RL Microcontroller Interface
I'm designing a board that needs to be programmable via USB and external TX/RX pins. I decided to use FT232RL ( http://www.sparkfun.com/datasheets/DevTools/Arduino/FTDI%20Basic-v21-5V.pdf ) for the ...
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Can I use MAX232 instead of a ICL7660 to make a split power supply?
For an opAmp rails I need positive and negative voltages i.e. Vcc, Vee.
I look for a good IC which is commonly used for creating split power from a single power supply. Many recommends ICL7660. I ...
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