[Coco] An X-10 usage for the Direct Connect Modem Pak

[K. Pruitt]

The Direct Connect Modem Pak #26-2228, without modification, works as a host 
for the CM17A "firecracker" RF transceiver .

I used the cable from a CM11A controller module which has a phone line 
connector on one end and a DB-9 female port on the other end to hook it via 
a male-to-male adapter to the CM17A module which also has a DB-9 female 
port.

The program I use to access the CM17A via the RS-232 Pak bit-bangs the DTR 
and RTS bits of the command register. The DC Modem Pak works the same way, 
just with a different address for the 6551, but it is still the DTR and RTS 
bit of the command register that gets hit. The same patterns to produce the 
logic codes with the RS-232 Pak apply to the DC Modem Pak. Baud rate is 
irrelevant to this application so the 300 baud limitation of the DC Modem 
Pak doesn't have any negative impact here.

All in all not a bad use for the Direct Connect Modem Pak considering there 
is no hardware modification needed and it adds RF control of X10 modules to 
the CoCo.

I haven't done any reliability checking yet. This is just my report on my 
"what if I plug this thing here in to this thing here" experiment.