Adafruit RS232 Pal - Two Channel UART to RS-232 Level Shifters

If you're looking to interface with telco, retro or industrial equipment you'll probably run into RS-232 interfaces. The Adafruit RS232 Pal - Two Channel UART to RS-232 Level Shifters is your friend in such cases, giving you two duplex channels of level shifting and taking care…

VIN
Board logic supply input. Adafruit Learn says to power it with the same voltage as the logic level of the microcontroller.
Type · powerVoltage · 3.3V or 5V logic supply, matching the microcontroller logic level
GND
Common ground for power and logic.
Type · groundVoltage · 0V reference
V+
Positive voltage rail output from the RS-232 connection, usable as a reference voltage.
Type · powerVoltage · RS-232 generated positive rail reference
V-
Negative voltage rail output from the RS-232 connection, usable as a reference voltage.
Type · powerVoltage · RS-232 generated negative rail reference
LV T1
Low-voltage side channel 1 logic data input from UART.
Type · signalVoltage · 3.3V or 5V logic

Start wiring

UART · 3.3V or 5V logic supply, matching the microcontroller logic level · 0V reference

Confirm the data interface matches your host board.

Module pins: VIN, V+, V-, GND, LV T1, LV R1, LV T2, LV R2. Schematik maps them to your board in the app.

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Pin	Type	Function	Voltage
VIN	power	Board logic supply input. Adafruit Learn says to power it with the same voltage as the logic level of the microcontroller.	3.3V or 5V logic supply, matching the microcontroller logic level
GND	ground	Common ground for power and logic.	0V reference
V+	power	Positive voltage rail output from the RS-232 connection, usable as a reference voltage.	RS-232 generated positive rail reference
V-	power	Negative voltage rail output from the RS-232 connection, usable as a reference voltage.	RS-232 generated negative rail reference
LV T1	signal	Low-voltage side channel 1 logic data input from UART.	3.3V or 5V logic
LV R1	signal	Low-voltage side channel 1 logic data output to UART.	3.3V or 5V logic
LV T2	signal	Low-voltage side channel 2 logic data input from UART.	3.3V or 5V logic
LV R2	signal	Low-voltage side channel 2 logic data output to UART.	3.3V or 5V logic
HV T1	signal	High-voltage RS-232 side channel 1 line data output to the remote RS-232 system.	RS-232 signalling, Adafruit notes this side can require about ±6V to ±10V
HV R1	signal	High-voltage RS-232 side channel 1 line data input from the remote RS-232 system.	RS-232 signalling, Adafruit notes this side can require about ±6V to ±10V
HV T2	signal	High-voltage RS-232 side channel 2 line data output to the remote RS-232 system.	RS-232 signalling, Adafruit notes this side can require about ±6V to ±10V
HV R2	signal	High-voltage RS-232 side channel 2 line data input from the remote RS-232 system.	RS-232 signalling, Adafruit notes this side can require about ±6V to ±10V

Pinout

Start wiring

Connectors

Displays

Air quality

MCUs and boards