Questions tagged [rs232]
RS-232 is the electrical standard used on most serial ports. Note that this standard is a +/- 15 volt system and requires a FDMI converter to make it compatible with TTL logic levels.
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Difference between UART and RS-232?
Most of the time RS-232 and UART come together in serial communication theories. Are they both the same? From my readings I concluded UART is a hardware form of the RS-232 protocol. Am I correct?
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Capacitor in RS232 level shifter. Data is strictly half-duplex
I have created a level shifter very similar to the schematic at: http://picprojects.org.uk/projects/simpleSIO/ssio.htm except for the capacitor I use 47nF because the page claims:
at high bit rates ...
user152879
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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 ...
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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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RS 232 serial sniffing
We have a task in hand to sniff a RS232 protocol in a certain industrial automation setting (we have been asked to do this legally by the manufacturing company itself). We are planning to send a ...
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Max Serial Cable Length?
What is the maximum length of serial cable I can use, to connection work properly? Is length of serial cable in connection with baud rate? I am using about 5 meter cable at speed 38400 bauds and RS232 ...
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Why does RS-232 need a stop bit? [duplicate]
This might be obvious but I don't understand why RS-232 needs a stop bit. I understand that the start bit is necessary to notify the other end about the beginning of a transmission.
Let's say we are ...
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How does this PIC board achieve RS-232 communication without a line driver?
All the develooment boards I have seen yet with serial communication support usually have MAX232 line trasceiver. However, I have come across this Olimex PIC-LCD development board that does not have ...
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RS232 hotplugging
I've noticed that when I connect/disconnect the RS232 cable to my micro-controller, I receive a garbage character at the other end (my pc).
Is there a way to prevent this?
I want to eventually move ...
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Implement serial port on fpga (verilog)
I don't know if this belongs here or stackoverflow. I assume here as although verilog looks like software it's actually describing hardware connections?
I have a Spartan-3AN evaluation board and I'm ...
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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 ...
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Connecting GSM SIM900A module with Ardunio
I have bought an SIM900A Mini V4 GSM module. Here is the module,
I want to configure with arduino to send and receive SMS.
Do I have to connect TXD of this module--Tx of Arduino & RXD of this ...
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Communication between multiple microcontrollers
I'd like to start implementing a system consisting of N microcontrollers (N >= 2 MCUs), but I would like to know the possibilities to let them communicate one with the other.
Ideally, (N-1) ...
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What is the meaning of "half bit" in this context?
In RS-232 specification, the stop bits can be 1, 1.5 or 2 stop bits...I wonder how it's possible to have half a bit?
Also some ADC math uses 0.5bit precision in the IC specifications/datasheet. Can ...
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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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