Re: CM15A and MisterHouse Module Starting Point

[nobody@xxxxxxxxxxxx (Dave Houston)]

Neil Cherry <njc@xxxxxxxxxxxxx> wrote:

>> X-10 still hasn't released any documentation on the protocol?
>
>Nope, I've nagged them (even contacted David Rye). They said they'd
>share and I've waited 9 months. I'm no longer developing software for
>X10 (but I'll support what I have). I'm going with Insteon. So far it
>looks promising (I know about the licensing issues, I'm working on
>that).

I like the Insteon concept, which you already know if you followed my
rambling review, but still have reservations based on their track record.
I'm also waiting to see what they do for wireless control.

I have designed two daughterboards for the CM15A (one RS232, one USB) which
replace the MCU with a socketed 16F88 and an SMT 12F683. The socket allows
the 12F683 to be programmed in circuit. The 16F88 can use a bootloader which
allows updating its firmware. The 12F683 handles RF (TX & RX) and controls
an ST485 which can interface with other RS485 nodes. I had planned
additional RF receivers on the RS485 network to handle multiple frequencies
and multiple protocols but that's open ended.

It's looking more and more unlikely that I'll have the energy to complete
firmware for them. I'm willing to make the designs open source if you're
interested in taking them forward.

The bare boards cost $2.50 each (plus postage) for QTY 1 and that's with
soldermask and silkscreen on both sides. They would cost about $0.10 each
(plus air mail from China) in any kind of quantity. I might be able to
arrange a P/N with the board supplier so that individuals could order them
at the $2.50 price.

The 16F88 has a USART and I use a triple inverter for a 0-5V RS232 link. It
does require a conversion cable (USB to DB9) but that's pretty simple. The
USB version uses Silicon Lab's CP2102 which is a better (and much smaller)
single chip USB-serial bridge that only requires a couple of bypass caps.

The passives are 805 size which I think is the smallest that can be hand
soldered (even by a lame, spastic geezer like me) but it's easier to do all
of the SMT soldering in a toaster oven. There's probably no way the CP2102
can be hand soldered.

The completed boards should cost in the $12-17 range.