Recent content by vshortt

This is a theoretical question. I know that there are 4 program slots on a 28x2. Slot 0 is the default. I also know that you can store additional programs on a memory chip (24LC512, lets say) and then run them using the i2c bus. The problem is that when you do this, the i2c bus is "locked...

Good grief, thought i had that solved. Sorry. Posted the wrong schematic. Here you go.

Hi All, I'm building a circuit that needs to be able to detect whether the incoming voltage is 12-14v or 24-28v DC. The detection is the easy part. Use a voltage divider and send the result to an ADC pin. Easy. The part I'm concerned about is overvoltage. If for some reason more than about...

Okay, I think I have a better understanding of how a MOSFET works. I appreciate evryones input. Here is the final circuit (complete this time) - take a look. I'd really like to make it as bullet-proof as possible, so what protections should be added? Dippy I know you said I don't need to run...

I guess I just don't see what I would gain with circuit #2 in the pic below, the top circuit is EXACTLY what I'm running right now. If there's a substantial advantage to the bottom circuit, I'm not opposed to using it, I just don't see what I would gain. I'm open to an education here. I know...

I thought I would go ahead and post the solution to my problem. It all had to do with the flywheel diode across the motor. Part of the downside of being a simple hobbyist and learning as you go is not fully understanding the function of a part in a circuit. I must admit I have been guilty of...

PWM Motor Control, MOSFET getting VERY hot? - SOLVED!!! Hi all, it's been a while since I've posted, but I hope someone can shed a little light on my latest project. This is a simple project using a 20X2's PWM function on C.5 to manage the speed of a fairly high powered blower motor. The motor...

I will most likely never stop using picaxes for various projects, but being what they are, they have many limitations, so I am looking to graduate from the picaxce to a more powerfull microcontroller. I would be interested in hearing recommendations on what people think the next step should...

okay, I need to know, how critical are decoupling capacitors in a well-rounded circuit that uses relays, temp sensors, serial transmissions, and i2c bus and a buck/boost power suppy. What recommendations do you have as to size, type and placement? seems like every place I turn to has a...

Okay, I may have missed the documentation on this odd little quirk, tell me if It's documented somewhere: If I use the readtemp command on c.7 on a 20X2 while having b.1 and b.2 held high, the readtemp command causes b.2 to go low during the command. Afterward, b.2 goes high again. I tried...

Hello all, I have seriously run out of space on one of my 20x2's. I've done everything I can to make sure I have squeezed every last bit out of it! So my next questions is this: is it possible to run code from another chip? for example, if we have one chip talkting to a 24LC512 via the i2c...

Hi all, is it possible to have two picaxes reading and writing to a single i2c memory chip? I am working on a project that needs to be able to do just this. I am using two 20x2's and a single 24LC512. wiring them up isn't a problem, but I'm not sure how the i2c timing would work. having a...

Hi all, I did a quick search and didn't find anything so I thought I'd post. I'd like to use a 16 position BCD swith to "tune" a radio I'm working on. simply put, at the switch is turned clockwise, the radio tunes UP in frequency, as the switch is turned counter clockwise, it tunes DOWN. Is...

Do you guys know of a way to prevent the memory in the Picaxe, once loaded with variables using the EEPROM command, to retain the data instead of resetting all the values to zero? I'd like to be able to store some data in these locations instead of using an external memory chip like the...

I don't think I'm doing anything too difficult here, but the picaxe editor won't seemto let me do it... so where's my goof up? I'm trying to load 2 programs into 2 slots... here's what I'm doing: PROGRAM 1: #slot 0 #no_data ... program code... if pinC.6 = 1 then run 1 endif With this code...