Help USB to RS232 - How to test


New Member
How do I determine if the USB port is actually getting data to/from the system's COM port?

Some info:
- I have Vista Home Premium
- I purchased a Generic USB to RS232 adapter (from China) based on a PL2303 chip.
- The driver that came with the adapter seems to have installed properly.
- I have RealTerm installed.
- I jumpered Tx to Rx plus other pins on the male DB9 connector.
- I sought help from Prolific (re PL2303), but found nothing helpful.

But I don't know how to look for data passing through the adapter. What I type on the keyboard does not show up on the RealTerm screen.
I've worked with RS232 for years, and know about the signal-type on the USB port.
But now I am stumped, and about to cut the vinyl covers of the adapter.

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