# How to convert a single rs232 signal to ttl?

**URL:** <https://forum.core-electronics.com.au/t/how-to-convert-a-single-rs232-signal-to-ttl/9708>\
**Category:** Uncategorized\
**Created:** [24 March 2021 07:54 UTC](https://forum.core-electronics.com.au/t/how-to-convert-a-single-rs232-signal-to-ttl/9708 "2021-03-24T07:54:41Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![spencer158188](https://avatars.discourse-cdn.com/v4/letter/s/ecd19e/32.png) [@spencer158188](https://forum.core-electronics.com.au/u/spencer158188)\
**Post date:** [24 March 2021 07:54 UTC](https://forum.core-electronics.com.au/t/how-to-convert-a-single-rs232-signal-to-ttl/9708/1 "2021-03-24T07:54:41Z")

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Hey guys, here’s the deal, I was [trying to use max3232 to convert rs232 to ttl,](https://www.apogeeweb.net/circuitry/max3232-introduction-pinout-datasheet.html) the chip I’m using is from ti, but the problem is I just want to convert a single RS-232 signal to TTL, so the question is would it be enough to just hookup VCC, GND, R1\_IN and R1\_OUT? Or do I also need to connect the pump capacitors and if so, why? I need to convert a single RS-232 signal to TTL, maybe I can use a simpler chip even for that. I can’t seem to find such a chip though.  
Thanks a lot.

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**Author:** ![Liam120347](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/liam120347/32/5003_2.png) [@Liam120347](https://forum.core-electronics.com.au/u/Liam120347)\
**Post date:** [26 March 2021 06:06 UTC](https://forum.core-electronics.com.au/t/how-to-convert-a-single-rs232-signal-to-ttl/9708/2 "2021-03-26T06:06:58Z")

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Hi Spencer,

Did you mean UART(serial communication) I would check this one out here to do that:[RS232 to Serial Converter Australia](https://core-electronics.com.au/rs232-to-serial-converter.html)

TTL is the range at which transistors are ‘activated’ [Logic Levels - learn.sparkfun.com](https://learn.sparkfun.com/tutorials/logic-levels/ttl-logic-levels)

Liam.

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**Author:** ![Jeff105671](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/jeff105671/32/3729_2.png) [@Jeff105671](https://forum.core-electronics.com.au/u/Jeff105671)\
**Post date:** [27 March 2021 00:28 UTC](https://forum.core-electronics.com.au/t/how-to-convert-a-single-rs232-signal-to-ttl/9708/3 "2021-03-27T00:28:32Z")

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The pump capacitors are needed to create the +/-10v from Vcc. If you are only going from RS232 to TTL (whether one channel or both channels) you probably don’t need them. If you were going from TTL to RS232 you _might_ get away without them but that depends on the receiving equipment for the RS232 signal, cable length, etc. Whatever, there doesn’t seem much point in leaving them out. I am not aware of a single chip solution that is simpler than the MAX232, but you would be able to put something together from a BC547 or similar and a couple of resistors. But RS232 is tricky enough to get working without having to wonder about your signal levels.