stamp used as rs-232 converter
Archiver
Posts: 46,084
hi stamp freinds,
what i am looking for is a stamp circuit that would accept a 0-5
vdc differential input out of 1 or 2 sensors and convert to a rs-232
signal
that my computer can read on my com port.
i need about 16 bit resoultion and 100-250 ms speed, is this
possible? and does any one have a current design ?
thanks alan
what i am looking for is a stamp circuit that would accept a 0-5
vdc differential input out of 1 or 2 sensors and convert to a rs-232
signal
that my computer can read on my com port.
i need about 16 bit resoultion and 100-250 ms speed, is this
possible? and does any one have a current design ?
thanks alan
Comments
It looks like there are two distinct parts to your project:
1) Converting the Analog input of 0 to 5 volts to Digital with a 16 bit
resolution, and
2) Sending the 16 bit data as Serial output.
Firstly you would need a Serial ADC to get your voltages into a 16-bit
digital representation (since a parallel ADC would use all 16 stamp I/O pins
for your required resolution). There are lots of examples of doing this
available on the web with lower resolutions (12-bit, etc). See Stamp Manual
page 357 for an App note using the LTC1298.
As for the second part, use the SEROUT commands to send the output to any
Stamp pin but be aware that the Stamp uses TTL voltages (0-5V, Logic 0 and 1
respectively) to and that true RS-232 uses +12V to -12V (Logic 0 and 1
respectively). To achieve these voltage levels you would need to use
something like the LT1181ACN. See Basic Stamp Manual page 14 for more
details on this.
Hope this gets you started...
Lance.
PS. All references to the stamp Manual are for version V1_9.
>
Original Message
> From: apaine.musem@m... [noparse]/noparse]SMTP:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=262jwliS96wuhWBMpRHwK51jX5Z-3X99bXaCZUS2dZD5xAR76NRsBo_74HFLQUWmpm4ETjF462K9v1e3Dc4loiFO]apaine.musem@m...[/url
> Sent: Thursday,31 August 2000 11:18
> To: basicstamps@egroups.com
> Subject: [noparse][[/noparse]basicstamps] stamp used as rs-232 converter
>
> hi stamp freinds,
>
> what i am looking for is a stamp circuit that would accept a 0-5
> vdc differential input out of 1 or 2 sensors and convert to a rs-232
> signal
> that my computer can read on my com port.
> i need about 16 bit resoultion and 100-250 ms speed, is this
> possible? and does any one have a current design ?
>
>
> thanks alan
>
>
>
>
>what i am looking for is a stamp circuit that would accept a 0-5
>vdc differential input out of 1 or 2 sensors and convert to a rs-232
>signal
>that my computer can read on my com port.
You could do this relatively easily with an ADC connected to the stamp.
Read the ADC with the stamp, then send the data out serially...maxim makes
some great ADCs.
>i need about 16 bit resoultion and 100-250 ms speed, is this
>possible? and does any one have a current design ?
I'm not sure what you mean by "100-250ms speed". One ADC sample every 100
to 250 ms? This should be easily within reach.
Duncan