Wimodem232 Pro, trying to get it to work

[cathrynmataga]

I just got it. With just power, it's just black screen. I tried three cables.  When I connect to a PC USB port I do see the LED closest to the power connector blink a few times.  The little screen never shows anything.   With RS232 connected (this is 2GS with a Mac RS232 cable) I see blinking on the first and fourth LED closest to the RS232 connector blink, but still the little screen neer shows anything.  I tried setting to 300 baud and I'm trying to talk to it, but I get no response (though possibly user confusion.)
I'm concerned that the screen never shows anything though.  I don't see anything like a power switch on here.