Networking the BS2SX
Archiver
Posts: 46,084
Original Message
From: Steve Percy <percy@p...>
To: Basic Stamp eGroup <basicstamps@egroups.com>
Date: Wednesday, November 29, 2000 1:12 PM
Subject: [noparse][[/noparse]basicstamps] Networking the BS2SX
hi steve
i have recently finished a machine (i lie, it'll never be finished) that
makes aluminium (aluminum for our us friends) frames.
this machine is run by 5 bs2's and 1 bs1 all networked together.
prior to building it i only had stamps blinking leds etc.
this machine has to accept inputs from switches and turn relays
on and off in a particular sequence.
i found that networking the stamps was extremely painLESS,
worked 1st time, no problem .
i dont need to communicate with a pc (except for programmimg the stamps so i
cant help on that score).
i have set the stamps up as master,groucho, chico, harpo,and zeppo
to make sure the right stamp gets the right message.
each stamp has control over a part of the machine , all controlled
by the master stamp.
after running the machine today i have come to the conclusion that the
master bs2 needs to be a bs2sx to give me more conrtol over it.
i can probably help you with networking but not with bs2-pc communication
regards ian
>:
>
>>
>>
>>>
>?
>.
>
>>>
>>
>IT.
>--
>>
>
>
>
>
>
>
Comments
>Hi there
Hi Steve -
>This has probably been covered before, although a search of the group
>failed to find a definitive answer.
>I have to network 4 BS2SX stamps, which have to talk to each other, report
>back to a host PC and also receive commands from the host PC, as well as
>read switches, activate relays etc.
Is this for a hobby application, or a commercial effort ?
>Is it better to :
>a) Have the stamps and the PC on a 3 wire (Rx, Tx, Gnd) network using
>open baud modes.
>b) Have only one stamp to communicate with the PC, relaying commands to
>and fro.
>c) Use the RS-232 programming ports for the link.
>d) Assign other pins for the link.
>
>Although I have used stamps for lots of different industrial applications,
>this will be the first time that networking is required.
>
>Has anyone out there done this ?
>Any thoughts, schematics, code etc. would be most welcomed.
I sincerely doubt that anyone could devise one system that works best in
all cases. That being a given, it really depends on what you want to
accomplish. SERIN/SEROUT may NOT even be the best approach. I too had
limited my thinking to that sort of networking as described in the manual
and in many of the books. Since that manual was originally written some
years ago, many advances have been made in micro-processoring networkng
that take the entire matter far beyond what was originally proposed there.
>I have read the serin and serout sections of the manual, but can draw no
>definitive conclusion from this.
>Don't limit yourself to the book. Consider also Shiftin/Shiftout
>techniques, and possibly even using an intermediary (PIC or other)
>processor as a "hub". Take a look at I2C (Philips), MicroWire (National),
>ModBus (many PLC's), MicroLan, Lon Works (Echelon), and many other
>networking protocols. Another interesting protocol is SNAP which is a
>open, scalable, network designed in Scandanavia
>[noparse][[/noparse] http://www.hth.com/snap/ ] which certainly deserves consideration.
There are Ethernet/LAN any_Base solutions, twisted pair, RS-485 adapters to
RS-232 in affordable small PCB packages (~$40.00 US), and more coming up.
It really depends on your direction and specific needs.
If you have some time on this - DON'T jump to any one solution right now.
You will be pleased that you didn't. I'm not at liberty to say too much
more, but there are packages in the works as we speak to address this issue.
Feel free to contact me offlist for more information.
Thanks in advance....
>Sure
>Me... Putting the DIO back into IT.
>--
>Regards
>Steve Percy
>Penguin Technologies 5 Harbour Elbow
>Banksia Grove Western Australia 6031
>Phone : 61 8 9405 7000 Fax : 61 8 9405 7111
Regards,
Bruce Bates
This has probably been covered before, although a search of the group
failed to find a definitive answer.
I have to network 4 BS2SX stamps, which have to talk to each other, report
back to a host PC and also receive commands from the host PC, as well as
read switches, activate relays etc.
Is it better to :
a) Have the stamps and the PC on a 3 wire (Rx, Tx, Gnd) network using open baud
modes.
b) Have only one stamp to communicate with the PC, relaying commands to and
fro.
c) Use the RS-232 programming ports for the link.
d) Assign other pins for the link.
Although I have used stamps for lots of different industrial applications, this
will be the first time that networking is required.
Has anyone out there done this ?
Any thoughts, schematics, code etc. would be most welcomed.
I have read the serin and serout sections of the manual, but can draw no
definitive conclusion from this.
Thanks in advance....
Me... Putting the DIO back into IT.
--
Regards
Steve Percy
Penguin Technologies 5 Harbour Elbow
Banksia Grove Western Australia 6031
Phone : 61 8 9405 7000 Fax : 61 8 9405 7111
much more depending on the environment.
For long distances, use RS-485. TTL-to-RS-485 converters/tranceivers are
easily available. Communication is over two wires, so your code will need
to ensure that only one device is talking at a time. One way to do this is
to declare one node the master and have the other nodes transmit only when
the master requests it. You'll need an additional port pin on each node to
control the transmit-enable input on the RS-485 transceiver (unless you use
an automatic hardware-only circuit).
RS-232 is designed for use with 2 devices only.
I have info and example code for an RS-485 Stamp/PC network here:
http://www.lvr.com/serport.htm
Jan Axelson
http://www.lvr.com
jan@l...
>I have to network 4 BS2SX stamps, which have to talk to each other, report
back to a host PC and also receive commands from the host PC, as well as
read switches, activate relays etc.