Inchworm project started

[3v0]

It also needs power, some people don't hook up a wall wart to it and wonder why it doesn't work...

The power and gnd come through the ICSP cable.
Why does it not work ?

 

[williB]

i did not notice any activity on pin 8 or pin 13 when i just scoped the max232 chip
this is R1in and R2in
i think you are right about the com port problem , any other sugestions?
note this is the same cable i used last night to test the serial port communications with my meter , the meter has rs232 communication capability.
and it worked

the signal may go by so quickly that i did not see it , but it isnt likely.the beam didnt budge.
to sum up :
a working cable
a working com port
yet no detectable signal, from the com port,

 

[blueroomelectronics]

The power and gnd come through the ICSP cable.
Why does it not work ?

Opps my bad, yes it can be powered from the target too...

 

[blueroomelectronics]

i did not notice any activity on pin 8 or pin 13 when i just scoped the max232 chip
this is R1in and R2in
i think you are right about the com port problem , any other sugestions?
note this is the same cable i used last night to test the serial port communications with my meter , the meter has rs232 communication capability.
and it worked

the signal may go by so quickly that i did not see it , but it isnt likely.the beam didnt budge.
to sum up :
a working cable
a working com port
yet no detectable signal, from the com port,

Is this a USB to RS232 or a true RS232 port?

 

[williB]

its a true rs232 port

 

[williB]

pin 8 holds fast at minus 12V
pin 13 at plus 12V

 

[williB]

i have switched to com 1
Ran a terminal program ( from mikropsacal)
set the flow control to NONE (in the device manager for windows) and got a signal when i transferred a file

so the port seems to be working.

 

[williB]

i got a blip from pin 12 ! on the max 232 chip.when i try to connect.
which is R2 out , which goes to pin 26 ,the recieve line on the 877

so i'm gonna assume the com port is working.

 

[williB]

success!

i had a bad crystal!

 

[3v0]

i got a blip from pin 12 ! on the max 232 chip.when i try to connect.
which is R2 out , which goes to pin 26 ,the recieve line on the 877

so i'm gonna assume the com port is working.

You have it workng, contrats.

FWII the easyest way to test the rs232 is with a loop back type test. Remove the PIC and jumper the TX and RX pins at the processor socket Then connect to the Inchworm with any terminal program. If you can see what you type the MAX232 is working. When you remove the jumper you should not see what you type.