RE: C-Bus gateway update Aug 17th

[Kevin Hawkins]

Well - as promised I've uploaded a small picture of the newer xAP to C-Bus
gateway boards based on the RCM 2500 Rabbit cores. Even I am astounded at
how poor my photographic skills are on this one, but I did get a decent
filesize this time. As you can see they are physically much smaller than
the
development boards and the keypad/display has gone away, plus the 3200 core
has now been replaced with the 2500 core.

This picture shows the actual boards that will be shipped in the first
batch. They have no solder mask (means not green) and four link wires on
the
reverse of the board but they have come out much better than I expected. On
the photo the power supply components are lower left, the C-Bus SIM with
the
2 wire C-Bus connection is sitting top right and the 2500 512K/512K Rabbit
core top left. The Rabbit core mounts onto the pcb via some matching
headers
and underneath it are the two surface mount Maxim RS232 level converters.
There are 4 on board LED's for Ethernet 'Link' and 'Activity' / C-Bus
'network' and 'activity'. Ethernet is 10Mbs 10Base-T via a standard RJ45
connector.

Included on this board are some .1" headers to access other I/O
functions
>maybe< at a later date. There are two unused serial ports that
support
RS232 levels and RTS/CTS hardware handshaking and some parallel I/O lines.
The serial port connections are brought out to the 20 way .1" header
on the
top left of the board so a suitable cable could be made to DB9 connectors
if
needed. (This cable is not provided with the board as I do not support the
extra serial ports yet). My first support will probably be for the serial
to
Ethernet xAP gateway function. Also all the Rabbit bus lines are brought
out
to the headers that sit vertically down the centre of the board. There is a
possibility of one more TTL (5V) level serial port (no handshaking) if you
connect to the small header directly on the Rabbit module (the programming
port)but this is an unusual 2mm pitch 10 way connector. As I now include an
Ethernet based downloader you don't need to get at the programming port
anymore so this has become available.

The power supply is connected to the 3 pin header bottom centre on the
board. In this photo that is not evident as the psu cable is obscured by
the
Ethernet cable and soldered to the rear of the pcb. You will need a 7.5-12V
DC regulated power supply. The heat generated by the board is directly
related to this voltage so I recommend 7.5V if you can find one or 9V
otherwise. In the board redesign I will go to a standard psu socket for
this
as it will allow of the shelf psu's to plug in.

The board is 184x206 mm and needs a height clearance of around 28mm, it can
be drilled for mounting holes if needed. I might pre-drill the corners.
This
is sort of the size of two credit cards - but a little thicker ;-). Later I
am going to investigate a small case and a suitable wall wart psu for those
that want it all tidy - although I can't promise how soon. It is a little
awkward as the Ethernet RJ45 is physically mounted on the pcb of course.

There is a small prototype area bottom left that >may< be used later
for a
couple of options. Such an option board might piggyback on the existing
headers or might require a couple of link wires. I have played with a
SitePlayer, XPort, CoBox and a radio link module in this area - they all
physically fit, in fact often you can fit two modules. I have photos of all
these if people would like to see. Although I left space for an external
embedded web server I am pleased with the performance of the inbuilt web
server that I have written so I don't think this is needed. I am toying
with including some pcb mounted switches, and possibly LED's on this area
to
send xAP messages or to control C-Bus loads. What do people think ? Do you
like coloured lights ??

So .. very near now. The first release will have minimalist web
configuration and xAP schemas that are subject to change. C-Bus group names
may not be initially supported - ie groups will report as a group number. I
will then release more/updated schemas based on feedback and work on
cosmetic improvements to the web pages and the dynamic web content. I do
hope later to have proper web screens to display and control C-Bus, and
there is an ftp server to allow you to upload our own pages even. All the
firmware is now internet updateable - either I can update your units
remotely from here (if your firewall permits) OR you can download firmware
and update locally. Later there is a possibility that the units may
automagically update themselves - but I need to think this through. Letting
you know there is an update is probably as far as I want to go !

Probably about a couple of weeks away now from receiving the C-Bus SIM's
and
being able to ship. For those who will be using their existing RS232 C-Bus
modules even closer, you will need to make up your own cable but I can
provide the pinouts. Cased units &amp; psu's I have not looked into
yet.

I will be sending an email to all the people who have requested one of
these
units - I have so far made 12 of these and all but two are allocated. If
you
contacted me then I have one reserved for you. I probably intend to make 12
more using these pre release boards (although solder masked) and then sit
back and see what transpires before going to a revised pcb layout which
will
remove the 4 link wires and add a standard psu socket, maybe even the DB9's
onboard.

Kevin