there must be a way ???

Archiver

Hi guys,

Thanks for the reply Jon W.,
So I can't download to the BS2sx with two wires.
Ok then, but as in my earlier post regarding the 'BS2sx RF Link',
what I really want to do is download a BS2sx program to an RF
transmitter(using a MAX233 for TTL level) and receive the program
(using the receiver) on the BS2.....Obviously allowing wireless
programming....there must be a way. The transmitter needs data in,
ground and VCC(5v), and thats it. Can any additional circuitry trick
the editor into allowing the download, somehow creating the 'echo'
that it's looking for ?? I saw a circuit with a 4.7k res. across the
TX/RX lines and a 1N914 in series with the RX line. That doesn't work
either!! Hope someone can help.

John King

Archiver

Hi John,

For a radio link to program the Stamp, check out,
http://www.electrowave.com/products/superscreamer.shtml
and support of "PBASCIC" protocol. The receiver has to reconstruct
actions on the action of the extra lines with proper timing. Also
for a supplement to the developer docs, see
http://www.emesystems.com/BS2clone.htm

-- Tracy




>Hi guys,
>
>Thanks for the reply Jon W.,
>So I can't download to the BS2sx with two wires.
>Ok then, but as in my earlier post regarding the 'BS2sx RF Link',
>what I really want to do is download a BS2sx program to an RF
>transmitter(using a MAX233 for TTL level) and receive the program
>(using the receiver) on the BS2.....Obviously allowing wireless
>programming....there must be a way. The transmitter needs data in,
>ground and VCC(5v), and thats it. Can any additional circuitry trick
>the editor into allowing the download, somehow creating the 'echo'
>that it's looking for ?? I saw a circuit with a 4.7k res. across the
>TX/RX lines and a 1N914 in series with the RX line. That doesn't work
>either!! Hope someone can help.
>
>John King

Archiver

> So I can't download to the BS2sx with two wires.
> Ok then, but as in my earlier post regarding the 'BS2sx RF Link',
> what I really want to do is download a BS2sx program to an RF
> transmitter(using a MAX233 for TTL level) and receive the program
> (using the receiver) on the BS2.....Obviously allowing wireless
> programming....there must be a way. The transmitter needs data in,
> ground and VCC(5v), and thats it. Can any additional circuitry trick
> the editor into allowing the download, somehow creating the 'echo'
> that it's looking for ?? I saw a circuit with a 4.7k res. across the
> TX/RX lines and a 1N914 in series with the RX line. That doesn't work
> either!! Hope someone can help.

Why not just use a transciever and wire up a reset generator that's
triggered off a break character? You could then wire OR (thru a diode) the
ATN line to the tx data (this would reset the stamp) and the bi-directional
tranciever would "just work".

The only other option would be to have two stamps remotely. One to program
the other.
--
Enjoy,
George Warner,
Schizophrenic Optimization Scientists
Apple Developer Technical Support (DTS)

Archiver

John-

Two wires is overkill: it can be done with one. All the information
that the Stamp end really needs for programming purposes is present
in the data stream present on the PC's TX line. To do this you do in
fact need something on the PC side of the communication path to
emulate a Stamp. Because nothing else looks, smells and quacks quite
like a Stamp, I recommend a Stamp. I'll call this Stamp A, and the
Stamp on the far end of the communications path (wire, RF, IR,
whatever) Stamp B. Stamp A is basically there to keep the editor
happy, although it also receives the program. Stamp B is the real
intended target of the program.

Here's the scheme I have used successfully with the program below.
You program Stamp A as usual. You also pick off the PC's TX data
from Stamp A pin 2 and feed that to Stamp B pin 2 via wire or
wireless technique. Stamp B also has a wire from its I/O 9 to its
pin 22 (RES), and a 22K resistor from its pin 2 to I/O 4. I/O 9 can
then reset Stamp B, and I/O 4 can be read to determine when the PC
TX line is active. If using a single actual wire, also connect
grounds.

Here's a simple program to illustrate:

'{$STAMP BS2}

LOW 8
FOR w1 = 0 TO 5000
IF IN4 = 1 then resetStamp
NEXT
HIGH 8

restOfStuff:
LOW 8: PAUSE 1500
HIGH 8: PAUSE 500
GOTO restOfStuff

resetStamp:
LOW 9

For this program an LED on I/O 8 lets you see the program the Stamp
is running and it lets you know when you can download a new program.
For about five seconds after power is applied or the program is
downloaded (while the LED is lit solid), any assertion of the PC's TX
line (such as occurs during the programming sequence) causes the
Stamp to reset itself via I/O 9. Assuming that the TX activity is a
new program download, the Stamp will come out of reset with TX still
asserted and it will go into its program download routine. After
five seconds have elapsed following power application or download
with no TX activity, any further assertions of TX are handled
normally.

If you change the values for the PAUSEs, you can see that a new
program has in fact been downloaded.

My thanks to the Good Dr. Tracy Allen for pointing out the
following: not all Stamps are created equal. Some run faster than
others (resonator differences, etc.). If Stamp A runs faster than
Stamp B, this scheme won't work, because the editor and Stamp A get
ahead of Stamp B in the programming process. Further, Stamp A and
Stamp B must of course be the same models.

Seems like some tweaking of this approach ought to provide for
remote Stamp re-programming over telephone lines, etc.

Regards,

Steve

On 6 May 04 at 13:49, jking77777 wrote:

>
> Hi guys,
>
> Thanks for the reply Jon W.,
> So I can't download to the BS2sx with two wires.
> Ok then, but as in my earlier post regarding the 'BS2sx RF Link',
> what I really want to do is download a BS2sx program to an RF
> transmitter(using a MAX233 for TTL level) and receive the program
> (using the receiver) on the BS2.....Obviously allowing wireless
> programming....there must be a way...