Hey guys,
quick update: got this working, at least on the gateway side -- haven't tried hooking up a node yet, that's next... Once I confirm that works, I'll add SOLVED to the title of this.
For the gateway, I went digging through the new driver code, looking for things to try and adding some debug writes, and found the code in RFM69_Initialise() where, if MY_RFM69_RST_PIN is defined, it will reset the radio. I already had the RST line on the RFM69HCW wired up, and had previously (with the old driver) manually added code to do it, but it didn't help...
But with the new driver from the dev branch (used by #define MY_RFM69_NEW_DRIVER) I just added
#define MY_RFM69_RST_PIN 6
to my sketch and now I get...
0;255;3;0;9;0 MCO:BGN:INIT GW,CP=RPNGA---,VER=2.2.0-beta
0;255;3;0;9;26 TSM:INIT
0;255;3;0;9;28 TSF:WUR:MS=0
0;255;3;0;9;36 TSM:INIT:TSP OK
0;255;3;0;9;39 TSM:INIT:GW MODE
0;255;3;0;9;43 TSM:READY:ID=0,PAR=0,DIS=0
0;255;3;0;9;46 MCO:REG:NOT NEEDED
IP: 192.168.0.215
0;255;3;0;9;1350 MCO:BGN:STP
0;255;3;0;9;1353 MCO:BGN:INIT OK,TSP=1
I had read somewhere that the Adafruit breakout normally pulls RST high and supposedly resets itself at power-on, but I guess that wasn't enough... Explicitly resetting the radio seems to have done the trick and may be required for the Adafruit RFM69HCW breakout.
Going to see if I can get the raspberry pi GW working now, since my curiosity is piqued
Thank you all for the help and input!
--Steve