I've had help/suggestions from some of you already, but now I'm wondrin' if it's a duff PV. Equipment is as follows: PV550 (2711-B5A3, ser F, rev L, frn 4.2). I know it's old, but this is the first time it's seen power. With the CP3 cable and RA-approved usb-232 converter, I can talk to a 503 processor ok using the DF-1 driver, auto-configured to: SLC-CH0/micro/Panelview, baud 19200, station 00, no parity, crc, 1 stop bit, full duplex. When I plug the cp3 into the PV550 (set to node 2, 19200), rslnx browser still shows the slc (crossed out) but no sign of the PV. The fault indicator on the screen is flashing, but I figured that was because there's no app. in it. The comm indicator flashes, but is ok when connected to the 503. I keep coming back to it, hoping a fresh approach will do the trick, but no go. Any takers? Thanks.