Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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.

0
votes
3answers
62 views

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 ...
0
votes
2answers
55 views

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 ...
2
votes
1answer
106 views

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 ...
4
votes
2answers
413 views

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 ...
1
vote
1answer
185 views

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 ...
0
votes
1answer
210 views

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 ...
-1
votes
1answer
83 views

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( ...
7
votes
1answer
864 views

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
0
votes
0answers
133 views

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 ...
0
votes
0answers
244 views

Sending Data with HC05 Bluetooth module

I have set of data that i want to send them via h-05 Bluetooth module.But data has variable baud rate and i don't know the baud rates.How can i do it?Is there any Bluetooth module that don't care to ...
1
vote
1answer
894 views

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. ...
0
votes
1answer
112 views

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 ...
0
votes
2answers
308 views

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 ...
0
votes
2answers
283 views

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.
3
votes
2answers
3k views

MAX232 circuit not working

I am designing a circuit using a MAX232. I have connected Tx and Rx of the MCU to the 11th &...
-5
votes
2answers
209 views

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 ...
1
vote
4answers
1k views

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 ...
0
votes
1answer
3k views

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 ...
0
votes
1answer
414 views

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 ...
0
votes
1answer
479 views

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: ...
2
votes
1answer
3k views

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 ...
0
votes
1answer
2k views

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 ...
2
votes
1answer
5k views

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 ...
-2
votes
2answers
445 views

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 ...
0
votes
3answers
562 views

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 : ...
1
vote
1answer
263 views

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-...
0
votes
3answers
7k views

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 ...
1
vote
1answer
615 views

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 ...
2
votes
2answers
929 views

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 ...
2
votes
1answer
749 views

Unpowered MAX232 - input 'leaking' into Vcc

My PC is connected to a MAX232 through a USB-to-serial cable. When everything is powered, there are no issues. However, when I turn off the power, the MAX232's \$V_{cc}\$ has a voltage of -0.5 V (...
1
vote
1answer
3k views

Interfacing barcode scanner with arduino using RS232

I want to connect a barcode scanner with Arduino. I used MAX232 to convert the levels. I have taken only 3 pins: 2(RX), 3(TX) and 5(GND) from the DB9 cable and given them to pins of MAX232 as shown in ...
10
votes
2answers
2k views

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 ...
-1
votes
3answers
375 views

MCU cannot communicate with Bluegiga WT12 module

I have the evaluation kit EK-WT12 for Bluegiga WT12 module being controlled by a TI Launchpad. I have used the evaluation kit to communicate to a computer with SPP profile and I have sent and received ...
1
vote
2answers
926 views

Speed problems in homemade RS232-to-TTL converter board

I'm still trying to debug this RS232-to-TTL converter board that I've made, shown below. Now I think I've narrowed down the problem to speed: it works fine at 57,600 baud; but it inserts some ...
7
votes
2answers
8k views

Problems with homemade RS232-to-TTL converter board based on TI's MAX232

I've designed an RS232-to-TTL converter board based on TI's MAX232 IC that I plan to use to program a few custom Arduino boards that I have. However, I'm having trouble with the board and I'm hoping ...
1
vote
2answers
1k views

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 ...
0
votes
1answer
1k views

Connecting 4 devices on RS232

I have two PCs (very old, without usb but rs232 port) that talks via RS232. They send to each other very small bit of info ( one character every 10sec). Now I need to connect additionally two sensors ...
1
vote
2answers
969 views

Is it possible to construct a USB to UART bridge using MAX232 or TUSB3410 IC?

I am trying to build my own Arduino board. But for connecting it with a PC a USB to UART bridge was required. Even though I can buy it from sparkfun, I wanted to build my own bridge using some sample ...
1
vote
1answer
396 views

Connecting UART of ATmega16 to XBee

I am using the UART of ATmega16 for transmission. It is connected to XBee using a development kit which already has a MAX232 IC. How can I use the UART of ATmega16 with XBee? The other XBee is ...
-2
votes
1answer
2k views

3.3 v TLL to RS232 (To Connect Pic with PC)?

Is there any ic like MAX232 that can level shift 3.3v TLL to RS232? I need it to debug a pic running on 3.3 V with my pc.
1
vote
0answers
392 views

Error reading characters over serial on ATmega8 using CVAVR (USART)

I am trying to program ATmega8 for testing purposes using CVAVR as cross compiler and avrdude GUI as burner. Though I am able to burn the program, I think I am missing something in the coding part. It ...
5
votes
1answer
2k views

How to connect RS232 (“Opto-RS232”)

--Background-- I'm setting up a pretty standard RS232 interface from a digital caliper to a microcontroller, via a MAX232 chip (or in my case, MAX3222, which is the 3.3V-supply variant with 2 ...
6
votes
1answer
1k views

Why MAX232 works without any capacitors?

I was playing today with a very simple setup of pic16f876 and max232 connected to the COM port of a PC running a terminal emulator. I was just testing (the uc simply echoes anything it receives) when ...
0
votes
1answer
109 views

pinning of MAX232

I just want to ask if there is ever a connection between pin 2 and pin 3 of MAX232. I did a continuity test between those two pins. One of my MAX232 has shorted pin 2 and pin 3. My other IC does not ...
4
votes
1answer
874 views

Interfacing a PIC microcontroller to different logic levels

I'm planning on interfacing a PIC microcontroller to two devices which operate on two different logic levels and I'm wondering what the best way of approaching this is. I'm rather inexperienced in ...
0
votes
2answers
3k views

Arduino serial communication with printer

I'm working on a project with an Arduino Mega 2560. I connected the board to a MAX232CPE in order to communicate in serial mode with a thermal printer. I connected the MAX232 to one of the 3 extra ...
2
votes
2answers
4k views

Using MAX232 to fix prolific usb to serial voltage levels

I have a hobby PIC programmer (K8048) that uses rs232 to communicate with PC. My new laptop doesn't have rs232 port so I bought a prolific usb to serial converter to interface with this programmer but ...
0
votes
2answers
13k views

Getting weird characters in hyper-terminal on serial connection of PC and Atmega-16

I have a Atmega-16 based board, connected via Max232 to pins 2,3,5 of a db-9 connector. The connector connects to a PC. I am getting weird characters on hyper-terminal instead of normal "Hello World" ...
0
votes
4answers
831 views

serial driver for full 3.3v uC to back-of-computer

I'm looking for an integrated circuit that can connect a lpc17xx (microcontroller) to the serial port on the back of a standard computer. The lpc17xx has a UART controller with 8 pins. RXD TXD CTS DCD ...
3
votes
2answers
4k views

PIC18F + MAX232 USART Bizarreness

Okay, I've been struggling with this for weeks, and it's blowing my mind. I have been working with PICs for a long time, and I'm very confused as to why I can't make my USART work. First off, a few ...