USB to TRUE RS232 Serial (-6/+6V)
This product is a USB to DB9 serial port adding RS232 serial port to your computer (via an USB port). It works with MacOS X, Linux and Windows.
Note that this provides (approximately) +6V / -6V serial (RS232) not 5V serial (TTL) which is good for old devices like GPS, handhelds, programmers, etc.
Cheaper RS232 cables 'cheat' and only provides 0-5V which is not enough for some devices. This RS232 converter do have a true voltage doubler/inverter to make it more compatible.
Remarks: In RS232, LOW logic level on RS232 are between +5 to +15V as HIGH are between as -5 to -15V. Some RS232 Interface are designed with the spec ranges of +3 to +15V and -3 to +15 (so they use either 3.3V or 5V as RS232 logic level). However not all the devices will be fine with logic as low as 3.3V and would requires at least 5V. So it is better to have an USB-to-RS232 able to generates voltages a bit higher than 5V.
This RS232 have been tested and worked great with bit-bang serial programmers and adapters. Notice that USB communication overhead will make this adapter slower than TRUE hardware serial ports (because of the high overhead of USB).
The adapter are FTDI-chip based for better performance and reliability. The drivers are available for pretty much every operating system and is very stable.
The 3 inners LEDs will helps in diagnostic communication issues:
- the power LED let you know when the adapter is plugged in and working
- the RX/TX LEDs are great to troubleshoot communication issue.
This is only for the older "PL2303" based converter
Using the older "gray" PL2303 converter? It comes with a CD but we strongly suggest using the most recent drivers from the Prolific Website if you're running windows and the 'fixed' driver for Mac OSX or the version for MacOS 64 bit. If you're using Windows 7 and you have issues, try the Prolific driver version 1.013.
Windows vs Linux/Mac user
We use this product from Linux operating system without issue (this should be the same on Mac). The new FTDI-chip based have a better support on Windows.
Can't install the driver on Win7/Win8, check the technical details here to disable signature checking.