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46  Using Arduino / Microcontrollers / Re: What bootloader should I use (AtMega1284P) on: June 30, 2014, 08:47:05 pm
I use ArduinoISP to program optiboot only my 1284s.
(I do use an Arduino without auto-reset to run the ArduinoISP sketch...)
47  Using Arduino / Microcontrollers / Re: Help with making a "cheat sheet" for Arduinos. on: June 30, 2014, 05:42:48 pm
1:  Can't download them.
File/Download as ... ?

2: Although one is for the MEGA, what is the first one for?  It just says ARDUINO.  Is that the UNO, Ether10, Eleven?
It's pretty old.  There was the Arduino, and there was the Mega.  At the time.  Diecimilla, I guess.  Pretty much all the 8/168/328 designs use the same "pin names" even when they have different physical layouts (Nano, etc.)

4: It doesn't show the pins with "built in pull up resistors".
That would be "all of them."  I mentioned that earlier...

I am also not sure the importance of the PCINT and PCMSK columns.
Just because they're features you're not familiar with (Pin Change Interrupts), doesn't mean that they're not useful to have documented.

Those two pages also overdo the SPI and I2C bus names.  They are listed in two columns for no good reason I can see.
Bottom-up vs top-down documentation.  The "special features" column documents (comments) on most of the features on all of the pins.  The SPI and I2C columns are for when "I need I2C, Where is it!"

What I want is a sheet which the person can print out/off at home for "that" project.
So...  It's a shared google-doc spreadsheet.  If you have a google account, you can copy it and rsort/add/delete whatever columns you want (including the addition of a blank column for you to fill in my hand on a printed copy, if you want.)  You should also be able to do that with your own spreadsheet SW if you download it.
No one is ever going to be able to produce a "thing" that is perfect for everyone.  This sort of open source "thing" where you can modify the parts you don't like is the next best thing. (HW, SW, Docs!)  I think that some of the pictures are "open source" as well.

48  Development / Other Software Development / State of SDhc cards? on: June 30, 2014, 06:43:19 am
When SDhc cards came out  (>2GB), I remember that there was some concern that the new cards were no longer required to support single bit SPI-mode access, and that we smaller users might be stuck with using 2G card forever, assuming they still existed.
Well, I haven't seen a 2G card for sale in quite some time.  Have the newer, bigger, sd cards contued to work with our tiny chips?
Are we comfortable that things will stay that way?
49  Community / Website and Forum / Re: Drop the boolean data type, its broken. (or fix it) on: June 30, 2014, 06:20:40 am
C and C++ agree on false==0.   I think I'd prefer to see
#define true (!false)
If thats still acceptable.
50  Using Arduino / Installation & Troubleshooting / Re: No /dev/tty.usbmodem on OS X 10.9.3 on: June 30, 2014, 03:06:57 am
Vendor ID 0x1a86 is apparently NOT an FTDI device (you have a Nano "clone", rather than a genuine article.)
Checking around, it seems that it is a "ch341" USB/Serial driver, and doesn't have a MacOS driver.
51  General Category / General Discussion / Re: Double Micro Push Buttons on: June 30, 2014, 02:51:55 am

DPDT switches are a lot more common, but they'll tend to be bigger as well.
52  Development / Other Hardware Development / Re: Restrict user of certain pin/peripheral? on: June 30, 2014, 02:38:04 am
You could use your own pins_arduino.h file to mark the relevant digial pins as "NOT_A_PORT" in the digital_pin_to_port_PGM array.  This would only protect against a particular class of users, and it would cause programs to fail "silently" in mysterious manner if they tried to use the pins, but it might be better than nothing.
53  Using Arduino / General Electronics / Re: Reasonable: 167 ohm from micro speaker? on: June 30, 2014, 02:30:50 am
167 ohms is surprisingly high - most "bud" earphones are 30 ohms.
I agree.  Could this be a magnetic non-speaker transducer?  Some (many?) phones are designed to "work with hearing aids", which means that they somehow simulate the old-style phone earphones WRT magnetics.  (or it could be a special speaker specifically designed for such compatibility.)
54  Using Arduino / Programming Questions / Re: T1 timer counter sketch on: June 30, 2014, 02:14:08 am
Arduino Digital pin 8 is chip pin portB0, which is "ICP1 (Timer/Counter1 Input Capture Input)" according to the datasheet.
55  Using Arduino / Microcontrollers / Re: Help with making a "cheat sheet" for Arduinos. on: June 30, 2014, 01:10:22 am
Pins 0 - 7 are grouped together but 0 and 1 are the RX and TX pins.
Pins 8 - 13 (and two more pins) are grouped together.
Be careful about "grouped together", because that changes from board to board.  For example, one a MEGA, the "grouping" is quite different.

2 - 7 are PWN pins.
Pins 8 - 11 are also PWM.
This is incorrect for an Uno.  PWM pins are 3,5,6, 9,10,11.

Pins 15 - 20 are the analogue input pins, but also there are sub-sets:
Two are the SPI bus.
This is wrong.  SPI does not share pins with analog.

Pins 2 - 7 (from memory) allow you to activate internal pullup resistors if you use them as inputs.
ALL the pins allow you to activate internal pullups.

You might like:
They are set up as spreadsheets so that you can sort by different columns, which I've found useful.  Potentially, anyway.
(not updated for R3
56  Using Arduino / Programming Questions / Re: I need a code explanation on: June 29, 2014, 05:38:53 pm
So the port 8888 is for clients using UDP or TCP and the port 123...
Internet connections (UDP or TCP) have two port numbers involved.  The "destination port" of a client usually defines the service being requested.  TCP port 25 is SMTP Email, 123 is Network Time Protocol.  The "source port" is supposed to be random and unique on the client, and should not conflict with any service that the client might be offering at the same time.  In this case, it looks like the programmer has chosen 8888 as the initial "random" port.
57  Using Arduino / Microcontrollers / Re: [Solved] ATMEGA8L with External Interrupts won't wake from sleep on: June 29, 2014, 05:31:17 pm
Note that ATmega8 and ATmega328 are different "families" of chips, not just members of the same family with different amounts of memory (like m168 vs m328)  The m8 is quite  a bit older, and is probably "primitive" in various ways.
58  Using Arduino / Microcontrollers / Re: PROGRAM A PIC WITH ARDUINO 2009 on: June 29, 2014, 05:28:25 pm
Do you have a higher voltage supply (~12V) and a HV switch?  While some of the newer PIC have a "low voltage programming mode" that is 5V only, the 16F84 is an old chip that will need HV on its Vpp pin to be programmed.
59  Community / Website and Forum / Re: Drop the boolean data type, its broken. (or fix it) on: June 29, 2014, 05:25:21 pm
Does the C++ spec mean that
if (Serial.available()) {  // blah }
is now slower (in C++) than
if (Serial.available() > 0) { // blah }
because it first has to convert the paren contents to "bool" for the sake of "if", and then check for "true"?  (As opposed to C, where it would just check for non-zero...
Or does the optimizer fix all that for us?

I'm not sure I understand the advantages of forcing bools to be only 0 or 1, aside from a sort of intellectual purity...
60  Community / Website and Forum / Re: Drop the boolean data type, its broken. on: June 29, 2014, 06:15:12 am
In C, the rule was that you should never compare a Boolean to true.
"if ((Boolean)57) print("true");" works fine.
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