I have a question. What does
I have a question. What does happen if you give around -5 V to your picaxe board? With the microcontroller in it? Does the whole chip fry? Or just that particular port?
Thanks rik.I think I got
Thanks rik.I think I got there in time. But I still get the “hardware not found error”. I am pretty sure the error is not with my PC or my COM port. I installed the axe027 drivers and tried it both in XP and vista(with their respective drivers).The cable is perfectly installed. I triend changing the COM ports too.How will I find if theres anything wrong with my PIC or board. I mean is there any way to figure it out by measuring the i/o voltages?
Thanks in advance.
better bring it into the forum
You’d better describe your specific problem in a separate forum post. Make sure to describe your circuit, your observations and your expectations. And where they don’t match. Also mention enough to convince people you read the manual. Thrice.
Wireless
Hey!! I’m new to robotics and I’m from abroad so excuse my english. I would like to ask if I can somehow connect something to Picaxe and control it wirelessly, real-time. I would like to have option to control bot realtime via computer.
Is it possible?
Xbee!
Xbee!
Re: Xbee!
yeah, it looks great, thanks! i dont get how to connect it to picaxe, but as i said, i am amateur, it will take me some tome to understant, but i’m happy i know about some way its possible. i was just thinking - if i make a bot, can i control it realtime with xbee connectedd to picaxe? and can i possibly connect some low-res webcam and transmit image through that connection? i saw a good data rates there, so i think only problem is how to connect to it
You can do anyhing like that
You can do anyhing like that 
(But start simple: Make an LED blink, then a speaker beep. Or look at the top menu, “Start Here”
thanks
ok thanks, i think i’ll try it soon, i just wanted to know if real-time control via picaxe is possible, so it’s great
I know - I have used this
I know - I have used this page so many times myself They should make such a page for every board out there 
Actually 6 V is correct
1 time use batteries have a higher voltage than 1.5, so actually six volts is accurate at the beginning of the battery life, but slowly goes down in voltage.
sd20
Do u know how to hook up sd20 to pic28x1 projectboard?
Yes. Read the manual on how
Yes. Read the manual on how to communicate over I2c
Digital input grounds
I am about to start my second robot and I will be using digital inputs for the first time. This is more of a point of curiosity but why are there only 2 grounds in the digital input area for 8 inputs whereas there are 7 grounds for 4 inputs in the analogue area? in the analogue area you would be able to insert a three pin connector but this is not so in the digital area. Also, why does the board not just come with pins soldered into the grounds? Is there an advantage to not soldering them all in right away?
Fair question. I can only
Fair question. I can only guess that they needed the space for the IR section.
As for why the didn’t include pins for all the contact holes, your guess is as good as mine.
Where to put buttons?
Hello, im currently (slowly) building a “dog” bot. I would like him to do a trick when you push a little button on his back. Where would I hook up such a button? My first guess is in the digital input section, but how wold i set that up? Thank you for any help!
You are damn right!And you
You are damn right!
And you really want to have a look at the PICAXE manuals
Section 1 - Getting Started - Page 13
from
PICAXE 28x1 and/or Arduino output signal current
Hello everybody,
I’m currently trying to put something together for some kids at my school (I’m a science teacher). We’re thinking of connecting either a PICAXE 28x1 or an Arduino to a relay switch that will control a 12V circuit which will run a pair of Volvo 240 car windsheild wiper motors.
My question is, what is the max output current that I could get out of either of these boards? Is it enough to throw a relay? I want to know because if the output current is not high enough, I will introduce a transistor into the mix to amplify the current between the controller board (again PICAXE, or maybe Arduino) and the relay.
As always, any help the collective wisdom can share will be very, very appreciated. Thanks!
Ian
Check the Picaxe Manual Part
Check the Picaxe Manual Part 3 for how to interface to different types of devices. The manual does not include relays, but if you follow the instructions for interacing a solenoid you should be fine.
Use a 5V relay. 5V is the needed voltage for the coil.The other contacts should rated be able to handle the wiper motors. Note how the diagram in the Picaxe manual includes a diode to handle the back EMF from the coil.
You don’t have to use a MOFSET like in the diagram. You could use a pair of NPN BJTs in a Darlington configurationan to handle the coil current.
If you are using the Picaxe project board, you can make use of the ULN2803A Darlington driver chip in the available slot. That would let you should be able to sink up to 800 mA, which should be enough current to trigger the coil of the relay without a separate BJT or MOFSET. You could use a separate power supply to run the relay coil through the Darlington, allowing you to use something other than a 5V relay. See the documentation for the Picaxe 28-in Project Board for how to use it with that chip.
Hi again Ignoblegnome,Thanks
Hi again Ignoblegnome,
Thanks for this info. It’s exactly what I was looking for. Although I understand the priciples of the Darlington pair, does it hold some advantage over a MOSFET? It just seems that it would be easier to wire up a mosfet than a Darlington. I will definitely make sure to include a diode to protect from spikes, but again I’m new to this. How are diodes rated, and what size would I need? Of course, I’m sure I can google this question if you’re short on time. THanks again for the help!
Ian