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Is RS-232 TTL compatible?

Is RS-232 TTL compatible?

The data conversation is done in a hardware dongle implemented in the cable. Although the RS232 standard defines RS232 to be a True RS232 interface, and TTL is actually not compliant with the RS232 standard, in practice the majority of the RS232 serial ports we connect scanners to are TTL ports.

Is TTL same as RS-232?

RS232 vs TTL: What’s the difference? RS232 more extreme voltages help make it less susceptible to noise, interference, and degradation. The minimum and maximum voltages of RS-232 signals are +/-13V, while TTL signals are 0 to 3.3V/5V.

What is TTL level RS-232?

This method of serial communication is sometimes referred to as TTL serial (transistor-transistor logic). Serial communication at a TTL level will always remain between the limits of 0V and Vcc, which is often 5V or 3.3V. A logic high (‘1’) is represented by Vcc, while a logic low (‘0’) is 0V.

How does a RS232 logic level converter work?

It derives the negative supply for the RS232 transmit data from the serial RS232 receive data line in a parasitic fashion. This means that the device it’s connected to must use voltage levels within the RS232 specification. You can’t for example connect two of these back to back since nothing is supplying the negative voltage.

How is data converted from RS-232 to TTL?

True or false: Data is sent from a PC’s RS-232 port at 9600 bits-per-second (bps), it’s converted to TTL by a MAX232 before reaching a microcontroller. The voltages of the signals look different on each end, but the speed (bps) does not change.

What’s the difference between RS-232 and UART logic?

Also the logic levels are inverted between the two types (excepting an option on a very few MCUs). To bidirectionally invert and convert between the UART levels and RS-232 levels one would typically use a chip such as the MAX232 (for 5V logic).

What’s the difference between RS-232 high and low voltage?

The two differ solely at a hardware level. By the RS-232 standard a logic high (‘1’) is represented by a negative voltage – anywhere from -3 to -25V – while a logic low (‘0’) transmits a positive voltage that can be anywhere from +3 to +25V.