Kevin Timmerman has developed an PIC based interface that will hook an inexpensive digital caliper to a PC via RS232. He has provided complete instructions including eagle schematic and board layout.

The link

The design uses a PIC12C509.

Common inexpensive calipers have a range would from 0 to 6in or about 150mm.

 

Good catch 3v0!

 

Thanks for the feedback. At times I am unsure if I am helping or just ticking people off by posting too much.

The only thing I do not like about the design is soldering the connector to the caliper. It looks like there should be a connector that plugs into it.

 

I think it is helpful. This project isn't finished, but is well documented, and will provide ideas for some.

As for the connector, I think it could be improved somewhat. I'm not sure I'll ever do this project, it is nice to know it is there, though! I could see it developing a lot further; I like the idea of 'things happening' in the absence of a human operator.

 

I agree. The real gem is not the project itself as the information provided.

 

hi,
i am trying to use atmega 16 microcontroller with a digital calliper,
i just want to use caliper's value as input in atmega.
i have tried using the data wire of caliper as input but no use.
but when i use an ldr sensor on the same port it works,may be because the data from the caliper is in digital form and from the sensor ,it is analog form?
any suggestion.

 

hi,
i am trying to use atmega 16 microcontroller with a digital calliper,
i just want to use caliper's value as input in atmega.
i have tried using the data wire of caliper as input but no use.
but when i use an ldr sensor on the same port it works,may be because the data from the caliper is in digital form and from the sensor ,it is analog form?
any suggestion

 

You figured it out. The data from the calliper is digital "Each burst contains 48 bits of data",

I suggest you study the article linked to in the OP. Keep in mind that the calliper is a 1.5V device and the uC will most often be +5. All covered in article.

__________________
search engine for electronic parts
Junebug USB PIC programmer kit., USB Bit Wacker, 3v0's Homepage
The 15 Minute Printed Circuit Board! (+drill time)

 

actually i want to use the caliper as encoder.
i attached a stepper motor to the development board i have with atmega16 microcontroller,now i want the motor to run untill a perticular value or desired travel is gained by the caliper.suppose 1000.
now i am a beginner with microcontrollers,i just get confused when i see those big circuit diagrams.
looking for help.

 

Since you are just starting with uC's porting this project from a PIC to AVR may not be a good project for you. Too complicated maybe?

It would be easier to use the project as is with the PIC in placeA and have the AVR read the data from the PICs serial port, but maybe that is not fast enough.

I would like to help but I have no idea what you can or can not do hardware or software.

__________________
search engine for electronic parts
Junebug USB PIC programmer kit., USB Bit Wacker, 3v0's Homepage
The 15 Minute Printed Circuit Board! (+drill time)

 

actually i just attended a workshop about robotics.
i have 4 years experience with machines.like lathe,milling and many more,
i got a development board at the workshop with atmega16 and two ports for two steppers, and 8 pins for sensors with adc.

now i want to drive two steppers in order to make a cnc moving bed.
and i want to use that caliper for better accuracy,
you know this way i will not have to care for the play in the screw.
just care for the value at the calliper.

any help has big value this time for me because my project is almost stopped.
or the other way is using rotary encoder. but i want to go for the caliper interface

thanks

 

actually i have a pdf file telling about the interface. it looks simple for you,i can understand the connections in the schematic. but the interface in the file is about caliper to computer inteface.
i think you will get what i want just after looking at the schematic..
i know i have to quit some part in the schematic,but don't know where.
beccause this schematic converts binary to cmos then ascii then transmit it to the pc via rs232.

and i have to stop after some connection.
here is link : http://www.compendiumarcana.com/caliper/

plz you just read it . reply even if you can't help.
thanks

 

There are several ways you could do this.

The first would be to port the authors code to the AVR.

You could use a PIC12C509 on the authors original PCB but change the PIC code to interface more smoothly with your AVR.

Last you could do as I said in the previous post and use the authors design as is and read its output with the AVR (I think this is too slow).

But if you do NOT know how to program a microcontroler how do you expect to do the project. Telling me you attened a robotic workshop does not tell me about your ability to do this project.

Could be a language/translation thing.

Can you write code in AVR assemble ?
Can you write code in PIC assembler ?
Can you write code in C ?
Can you write code in BASIC ?

__________________
search engine for electronic parts
Junebug USB PIC programmer kit., USB Bit Wacker, 3v0's Homepage
The 15 Minute Printed Circuit Board! (+drill time)

 

i know basics of programming the avr.
i am using bascom avr, and can program atmega16 to accept an input then do certain tasks ,like driving motors or just like sending any output to any of port and sensor callibration too.
in simple words i am a beginner.

so, should i forget about this project and start something simpler,if you think i can't do this.i will just do what u say ,
becoz you have more knowledge than me.

thanks

 

I would take your questions to the AVR Freaks fourms. If you want to use AVRs you will get more help there.

__________________
search engine for electronic parts
Junebug USB PIC programmer kit., USB Bit Wacker, 3v0's Homepage
The 15 Minute Printed Circuit Board! (+drill time)