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You are correct, those 0/5 V levels are not 'RS232' physical layer, which requires +/- 15 V. Many people say RS232, when they mean UART, the protocol, regardless of which physical layer is used to transport it. RS232 is perhaps the best known and oldest of the serial links, so it has become the Thermos, Hoover or BandAid word to describe them.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the TTL-like levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 0/3.3 V signal, it doesn't guarantee a 5 V output, and rarely gets near it, except with an external pullup.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify whether they do or not. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

In this poorly specified realm, especially on products acquired through AlliBayZon, it's caveat emptor, though chances are everything will just work. This is OK for hobbyists, where failure is an option. Professionals will buy through proper channels, read data sheets, and won't get caught out.

You are correct, those 0/5 V levels are not 'RS232' physical layer, which uses up to +/- 15 V. Many people say RS232, when they mean UART, the protocol, regardless of which physical layer is used to transport it. RS232 is perhaps the best known and oldest of the serial links, so it has become the Thermos, Hoover or BandAid word to describe them.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the TTL-like levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 0/3.3 V signal, it doesn't guarantee a 5 V output, and rarely gets near it, except with an external pullup.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify whether they do or not. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

In this poorly specified realm, especially on products acquired through AlliBayZon, it's caveat emptor, though chances are everything will just work. This is OK for hobbyists, where failure is an option. Professionals will buy through proper channels, read data sheets, and won't get caught out.

You are correct, those 0/5 V levels are not 'RS232' physical layer. However, they are RS232-like. Lazy people, and suppliers catering to hobbyists, do not make the distinction. They are very likely to work in your RS232-like application.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 0/3.3 V signal, it doesn't guarantee a 5 V output, and rarely gets near it, except with an external pullup.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify it. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

In this poorly specified realm, especially on products acquired through AlliBayZon, it's caveat emptor, though chances are everything will just work. This is OK for hobbyists, where failure is an option. Professionals will buy through proper channels, read data sheets, and won't get caught out.

You are correct, those 0/5 V levels are not 'RS232' physical layer, which requires +/- 15 V. Many people say RS232, when they mean UART, the protocol, regardless of which physical layer is used to transport it. RS232 is perhaps the best known and oldest of the serial links, so it has become the Thermos, Hoover or BandAid word to describe them.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the TTL-like levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 0/3.3 V signal, it doesn't guarantee a 5 V output, and rarely gets near it, except with an external pullup.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify whether they do or not. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

In this poorly specified realm, especially on products acquired through AlliBayZon, it's caveat emptor, though chances are everything will just work. This is OK for hobbyists, where failure is an option. Professionals will buy through proper channels, read data sheets, and won't get caught out.

You are correct, those 0/5 V levels are not 'RS232'. However, they are RS232-like. Lazy people, and suppliers catering to hobbyists, do not make the distinction. They are very likely to work in your RS232-like application.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 3.3 V signal, it doesn't guarrantee 5 V, and rarely reaches it.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify it. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

You are correct, those 0/5 V levels are not 'RS232' physical layer. However, they are RS232-like. Lazy people, and suppliers catering to hobbyists, do not make the distinction. They are very likely to work in your RS232-like application.

The CH340 you link to, and just about every other cheap 'TTL RS232' converter, outputs and accepts the levels you have illustrated. However, there is one caveat, the levels are often 0 and 3.3 V, rather than 0 and 5 V. TTL is really a 0/3.3 V signal, it doesn't guarantee a 5 V output, and rarely gets near it, except with an external pullup.

Some modules are switchable 3.3/5 V output. I don't know whether 3.3 V modules will accept 5 V signals without damage. With luck they'll specify it. I would hope that 5 V modules would accept 3.3 V highs as inputs, it's on the edge of a CMOS high specification, though solidly high for 'TTL'.

In this poorly specified realm, especially on products acquired through AlliBayZon, it's caveat emptor, though chances are everything will just work. This is OK for hobbyists, where failure is an option. Professionals will buy through proper channels, read data sheets, and won't get caught out.