2 votes

How does this RS485 transceiver work?

The board is very questionable, or at least it may be made for some specific non-standard purpose, as there are many things that are not typical for a standard RS-485 interface. It is possible that ...
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2 votes
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How does this RS485 transceiver work?

The normal (idle) state of the Pico UART output is high; this turns the transistor on through R1 or R11, which disables the transmitter (DE low) and enables the receiver (/RE low). Received data ...
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  • 659
2 votes

How does this RS485 transceiver work?

An RS-485 bus has three states: high, low, and idle. An UART signal has two states: high and low; when the UART is idle, the signal just stays high. It is therefore not possible to reliably control an ...
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1 vote

MAX3232: Switch between RS-232 and TTL levels

Electrically, you can use a single interface circuit like that shown below to accept an RS232C voltages or TTL voltages. When RXD is approx. >0.7 V, the Q1 base diode clamps R1 to something like 0....
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1 vote

MAX3232: Switch between RS-232 and TTL levels

An RS-232 receiver that just conforms to the RS-232 specification would not work with TTL signals. But the MAX3232 switching levels (0.8 V/2.4 V) are reduced to be compatible with TTL. However, the ...
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