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hi Paul,
Your project arrived OK, most of the jumpers had come adrift from the BB's and the LCD had dropped out of the BB, it looks OK.
Plugged the URM into my test board, which uses a 16F877 that has been programmed with latest Oshonsoft Basic program that cycles thru Tempr and Distance.
Worked first time, the Ranges and Temperatures are refreshed and displayed every 0.5 Sec, spot on.!
The problems are due to the long leads and lack of decoupling capacitors also the ZIF socket does not connect firmly into the BB.
BTW: the PIC is a 16F628A in your BB, not a 16F648.
I will tidy the project up and let you know how the rebuild goes.
hi Paul,
Rebuilt the circuit on a base board using the blue BB for the LCD and the white BB for the 16F628A.
Reprogrammed the 16F628A to give 5 Temperature and Distance readings per second on the LCD.
The temperature sensor is mounted on the URM PCB, so as the PCB warms up so does the 'apparent' ambient temperature, its about +3C degs above ambient!
The original problems were due to intermittent connection of the ZIF in the blue BB,also the wires pushed in alongside of the PIC pins in the ZIF, long wires and no decoupling.
I have added decoupling and shortened all the jumper wires using my tinned solid wires.
Its working OK and is on soak test.
If you PM me your return address, I will post it back early next week.
hi Paul.
The project was posted back to you today by Post Office 1st Class Recorded delivery, should be with you by Thursday.
The Basic program that is in the 628A is attached to this post.
The BB's are lightly tacked to a backing board using a little hot melt adhesive, use your solder iron to melt the glue if you prefer the BB's to be loose.
Let me know when you receive the package and its all working.
Regards
Eric
BTW: I have put a few components in the packing box, that you may find useful for other projects
Hi Eric. All arrived safely and whata great job you've done of tidying everything up. I really need a good development board ;-).
The codeon the chip obviously works great but the forum posted code above doesn't. Just in case anyone else is trying this. You need to remove all the comments on the serour serin etc... Also remove the loop around the 'welcome'
Thanks VERY much for your help Eric. Next project is to get the URM on the robot and do some sort of interupt when it detects obsticles. - I'll be posting more code here soon.
Sorry about the Serout's in the posted program, I was planning to add a second Serial output that would output the ASCII format of the Temperature and Distance to your PC,
I still have a lot to do. The metal work is from an old hexcrawler from the states. The head is my design. I have all of the cad drawings done for a new model with 3DOF (better leg manipulation) - It just costs so much to get it laser cut :-(
I have designed the robot to be modular. I have a pic that controls the walking gates, A pic that will control the scanning head and the ultrasonics / tempereature and what I call at the moment the 'brain' module.
The idea being that everything feeds in to the brain and it tells the other modules what to do.
For example at start up the brain tells the head (scanner) to start moving left and right. The ultrasonic tells the brain if there any obstacles? where? left? rigtht? etc ....
A signal (probaly single wire serial) will then be sent to the walking module telling it to walk forward, left, right, etc.
I still have a VERY long way to go but hey not bad for a beginner ...
If you want a head by the way I have loads that I had made - they are laser cut aluminium - let me know and i'll pop one in the post.
Problems so far -
1) The walking gait is DIGITAL in it's movement. I want a more ANALOG type of movement.
2) The servo's i'm using aren't really up to the job. I think this is why its so analog. Maybe one day i'll with the lottery and get the AX-12 type servos.
3) 3DOF (degrees of freedom) on the legs. This will allow the robot to raise and lower better.
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