I need to put my Arduino Uno project into a closure and would like to have an external reset button. Could I connect a momentary switch to the reset ICSP and ground?
Yes.
Thanks, that's good to know 
In addition to this post, can the same be done with the Arduino Pro Mini using it's reset pin? I've read the overview of the mini which says pull the reset pin low, but I'm not quite sure what this means.
It means that to make it reset you connect it to ground - pull low - yes it works with all arduinos in fact I can't think of a processor whose reset was not active low.
Thanks. So I would hook up a basic momentary switch to either reset pin on my Pro Mini and one to ground?
Another question, would my external 9V batteries (x6 AA's) go to the Raw pin on the Pro Mini, then supply all my external sensors with the VCC on the Pro Mini?
daz1761:
Thanks. So I would hook up a basic momentary switch to either reset pin on my Pro Mini and one to ground?Another question, would my external 9V batteries (x6 AA's) go to the Raw pin on the Pro Mini, then supply all my external sensors with the VCC on the Pro Mini?
Yes, as long as 'all external sensors' don't in total require more current then the on-board voltage regulator can supply.
Lefty
Thats good news
Its just I'm thinking of transferring a simple data logging project from my Arduino Uno onto the Pro Mini I have just purchased so yes, all of my sensors are max 5v and minimum of 3.3v
The reason for the reset button questions is that I want to build everything into a project box of some kind.
retrolefty said, "Yes, as long as 'all external sensors' don't in total require more current then the on-board voltage regulator can supply"
I thought that may need pointing out.
Thanks for pointing that out.
As long as there is no difference between my 5v Pro Mini and Uno.
I'll try my data and time module with it using my FTDI to serial with the Pro Mini and see if all is ok.
Just an update.
My date and time module is printing out to the serial monitor ok.
daz1761:
Just an update.My date and time module is printing out to the serial monitor ok.
You've failed to understand what "current" is.
Put your finger on the voltage regulator on the Pro Mini (it's a black rectangle with five legs in the middle of the group of little components).
Is it hot when everything is running?
I'm new to electrons but I have a basic understanding of current.
The Arduino Uno R3 and Pro Mini (5v) dc current per pin is 40mA.
So far I have an I2c date and time module running. I've tried running this with my FTDI cable (5v) and I placed a pp3 9v battery into the raw pin and so far nothing seems to be overheating. However, its only been running a few minutes so far.
I'll keep testing the voltage regulator for heat issues too.
daz1761:
I'm new to electrons but I have a basic understanding of current.The Arduino Uno R3 and Pro Mini (5v) dc current per pin is 40mA.
That's the failure value, not recommended for constant use.
daz1761:
So far I have an I2c date and time module running. I've tried running this with my FTDI cable (5v) and I placed a pp3 9v battery into the raw pin and so far nothing seems to be overheating. However, its only been running a few minutes so far.I'll keep testing the voltage regulator for heat issues too.
The regulator won't heat up with the FTDI cable, only with a power source connected to RAW.
Be sure to do the finger test if you decide to power the final device via RAW. The regulator on a Pro Mini is tiny and easy to overheat.
Ah right I see, well thats the plan to use it constantly for up to 4 hours a session data logging with a few sensors and external power (x6 AA batteries as I like to have an LCD screen for info and debugging).
So they don't recommend constant use for the Pro Mini? Correct me if I am wrong, but would it be correct to say that the Pro Mini is designed for just 1 or 2 sensors as a semi/permanent fixture. I was thinkiing of connecting the date and time module, 16x4 LCD screen, SD reader and an Adafruit ADXL335 accelerometer, and then passing all my other sensors off to my Arduino Uno as its been outstanding so far with external power
I understand the V regulator is tiny so I'll start hooking some different sensors and using external power, whilst doing a finger tip test as you say.
I've tried running this with my FTDI cable (5v) and I placed a pp3 9v battery into the raw pin
By raw pin do you mean an arduino pin? I hope not.
Correct me if I am wrong, but would it be correct to say that the Pro Mini is designed for just 1 or 2 sensors as a semi/permanent fixture.
Your are wrong, depending on how you wire things up you can have as many sensors as you like.
and then passing all my other sensors off to my Arduino Uno
A two processor solution proposed by a beginner is nearly always the wrong thing to do.
Grumpy_Mike:
I've tried running this with my FTDI cable (5v) and I placed a pp3 9v battery into the raw pin
By raw pin do you mean an arduino pin? I hope not.
On a Pro Mini the "RAW" pin is unregulated voltage input (it then goes through the regulator...)
Grumpy_Mike:
Correct me if I am wrong, but would it be correct to say that the Pro Mini is designed for just 1 or 2 sensors as a semi/permanent fixture.
Your are wrong, depending on how you wire things up you can have as many sensors as you like.
A Pro Mini actually has 2 more I/O pins than an Arduino Uno (A6 and A7 are have connectors on the Mini, they don't on the Uno).
Grumpy_Mike:
I've tried running this with my FTDI cable (5v) and I placed a pp3 9v battery into the raw pin
By raw pin do you mean an arduino pin? I hope not.
Sorry I mean't in turn, not at the same time. My 9v pp3 went to the raw pin on the Pro Mini after I had tried it with the FTDI cable.
I've just been reading the SparkFun guide on the 3.3v/5v Pro Mini and they have something like this as a regulated power option:
Would this be a better or safer option to power a few sensors (temp, Photocell, Sd card, etc.) rather than a raw unregulated 9v?