Data logger clock and array

[skimask]

I have some experience with Proton picbasic.

You know this forum isn't for Proton picbasic right?

The data logger will be taking every 1s-10s samplings adjustable from Excel.

So Excel is going to talk to the PIC?

What do you think the best way to make 20 minutes Clock?

Make a whole bunch of 1 second clocks and keep track of them.

I've never used USB before but it might be a good idea to learn it.

There's one really really really good thread here on how to do just that using an 18F4550.

How to communicate between USB and excel? Would it not require custom PC software? Using serial port I can even use HyperTerminal to import the data.

Pull it in using that link I eluded to above, and dump the data to a .csv file, then import it to Excel. Or write a really cool VBA app to pull the data from the file as it comes in. Doesn't matter.

I'd like to keep data logger very simple without external parts. This is just a hobby project and I know once my friends would see the data logger I would have to make them as well. I'd prefer to keep the project with minimum parts so I wouldn't even need a PCB and it'll be easy to build it for my friends.

Now that's classic... And just how do you suggest doing that? Chips without a PCB... Are you going to mount this stuff on wheat bread or Pringles chips or what?
What exactly do you plan on datalogging again?

[PicLearner]

In order for me to keep it very simple it would take ADC from lipo cells which are 3.7v. I might use a resistor 4.7k on the connector it self or without a resistor since it shouldn't have any spikes in voltage. To take frequency I was thinking just to use 2 resistors 1k and 100ohm to drop the voltage. To power up the pic I was thinking to use TO-92 0.5% LDO and 1 or 2 small capacitors. I'm not going to use voltage reference to keep it simple and ADC probably should work within 1%-3% accurate. As you can see 1 PDIP microchip, 1 LDO, 1-2 capacitors and just connector glued and soldered directly to microchip. Using software rs232 I don’t need Max232 so I can just use serial female connector with 2 resistors and connect it directly to microchip whenever I need to upload the data. Sure I can make PCB at home but I just want to keep it very simple so my friends can use it as well just to pay for parts or so. I bought PicBasic just for fun since I like electronics and I don't intend to make profit but maybe I might sell it for a small fee. I have regular job which pays my bills and I don't mind to spend money for my hobby that I like.

[skimask]

To power up the pic I was thinking to use TO-92 0.5% LDO and 1 or 2 small capacitors.

You should be able to drive a PIC directly from one LiPo, no regulators need.

I'm not going to use voltage reference to keep it simple and ADC probably should work within 1%-3% accurate.

There's a few PICs out there that have a built-in .6v reference which you could 'reference against'.

As you can see 1 PDIP microchip, 1 LDO, 1-2 capacitors and just connector glued and soldered directly to microchip.

If you think it'll run, go with it... I don't think it'll run and last, but that's just me.

Using software rs232 I don’t need Max232 so I can just use serial female connector with 2 resistors and connect it directly to microchip whenever I need to upload the data.

Same thing with the USB, the connector, 2 wires to the PIC (D+/D-), an extra cap, and the right firmware.

[PicLearner]

double post deleted

[PicLearner]

Yeah I know. So far I love the forum, it's got so much info to learn from...

You know this forum is Proton picbasic right?

I was thinking to use Excel to change settings in microchip using PLX-DAQ or Realterm OCX example. I can adjust number of batteries, number temp sensors connected to pic just by using serout command to update EEPROM of Flash to store different settings.

So Excel is going to talk to the PIC?

Let's say I use interrupt for 1 second using 16bit timer. 8mhz / 4 cycles / 16bit timer 65536 = 0.000030517578125 multiply by 256 prescaler = 0.0078125. 1 second / 0.0078125 = 128. As I understand it should interrupt the software 128 per second. My guess it might conflict with a software running in the background or I'm wrong.

I would love to hear more about that.

PLX-DAQMake a whole bunch of 1 second clocks and keep track of them.PLX-DAQ

Very simple, please read my previous post.

Now that's classic... And just how do you suggest doing that? Chips without a PCB... Are you going to mount this stuff on wheat bread or Pringles chips or what?
What exactly do you plan on datalogging again?

[skimask]

Yeah I know. So far I love the forum, it's got so much info to learn from...

Let me try that one again...

You know this forum is for MeLabs PicBasicPro and not Proton Basic right?

[PicLearner]

Let me try that one again...

You know this forum is for MeLabs PicBasicPro and not Proton Basic right?

Yeah I know. That's what I said I bought MeLabs PicBasicPro but I've used Proton lite to learn on

[skimask]

Yeah I know.

Ok, just checking...

That's what I said I bought MeLabs PicBasicPro

Having trouble finding that particular sentence...

[PicLearner]

Sorry I didn't say what data logger is for. This is just for Remote Control airplanes/helicopter so I know what battery voltage is and motor RPM, temperature of the battery and speed controller. The main reason to use minumum external parts so it is very light because every gram counts on small electric RC helicopters. Everything looks very easy to make since I already did everything bit by bit by writing to flash and reading from flash. Getting ADC to work properly in 8bit and 10bits and CCP to ger RPM from the motor. Debugging the pic using RS232 and HyperTerminal but I just can't figure it out how to make clock. Can anybody please tell me if my calculation is right?
Let's say I use interrupt for 1 second using 16bit timer. 8mhz / 4 cycles / 16bit timer 65536 = 0.000030517578125 multiply by 256 prescaler = 0.0078125. 1 second / 0.0078125 = 128. As I understand it should interrupt the software 128 times per second. How do I figure it out if it will not conflict during ADC, CCP, EEPROM, CCP sampling, writing and erasing? I know I can disable interrupt routine during any of these sampling but it'll mess up the time. Is it even possible to do that without external RTC?

[skimask]

Let's say I use interrupt for 1 second using 16bit timer. 8mhz / 4 cycles / 16bit timer 65536 = 0.000030517578125 multiply by 256 prescaler = 0.0078125. 1 second / 0.0078125 = 128. As I understand it should interrupt the software 128 times per second. How do I figure it out if it will not conflict during ADC, CCP, EEPROM, CCP sampling, writing and erasing? I know I can disable interrupt routine during any of these sampling but it'll mess up the time. Is it even possible to do that without external RTC?

8Mhz / 4 = 2Mhz...
Clocking a 16 bit timer off the instruction clock @ 2Mhz = 2Mhz / 65536 = 30.517578125 interrupts per second (have to take the 1/x of the result, that's the part you forgot).
Set up the interrupt routine to count to 30, then take a sample. Yes, you'll be 16.69ms off for each second, unless you reload that particular timer at each interrupt with a correction factor to make it exactly one second. Look up the phrase PIC Multi-Calc.
If you clock an 8 bit timer off the instruction clock @ 2Mhz, 2Mhz / 256 = 7812.5 interrupts per second. Set up that interrupt routine to count to 7812, then take a sample. With the 8 bit timer, you'll only be 65us off in each second.