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Just tested on an Arduino Mega - so LED set to 13(B7), SQW connected to D2 (Int4) SDA, SCL VCC and GND connected. - the RTC does as expected - outputs a square wave (checked with oscilloscope) The Arduino doesn't wake from sleep on interrupt however. So remove the C code (sleep) in the loop - and ev...

And did that work?

Other things to check - pull ups on the sda and scl lines ( most rtc breakouts have them installed).
Can you read the time from rtc?

Martin

Just noticed:

Your code should give a 0.5s blinker. The clock outputs 500ms high then 500ms low pulse - the 1s is measured rising edge to rising edge (or falling to falling). Outputting the pin level should their give 0.5a on 0.5s off..

So for anyone to test: As a (pre)component (there is no simulation) - DS3231.fcpx ds3231 component.fcfx It's pretty much complete - apart from 12h mode (anyone any good suggestions on a suitable syntax - I lean towards Set12h mode and then taking the cue from the RTC value of this flag (and have a p...

Can you get my example to work? If no - RTC may be 'stuck'.

I'm just about to upload my 'component' version - I've added a RestartRTC macro (which might do the trick - clears EOSC and OSF flags)
If not then run the Arduino DS3231 set example or pull the power (inc battery)

Martin

A very simple blinkie - using the 1Hz SQW. Note i've used an Arduino Nano - so you'll need to change the LED pin (I've used a property for this) I'm just blinking the built-in LED on B5 blinkie.fcfx Note that this will work without sleeping the MCU (it will repeatedly output 0 or 1 to the pin) - 1kh...

I've tested my EnableSQW - and the results look good on oscilloscope - tested for 0-3 amd all results look good... Note - I don't test the range passed for rate (so passing a value other than 0-3 will give 'unexpected' results - it would be asy to add .RateSelect = .RateSelect & 0b11 if you want to ...

You need to force use of FP numbers so "253.0 /255 * 100" should work. It's currently calculated as an integer then converted on assignment. (note the .0 does the magic)

Martin

Can you post your code? I'm currently working on a new DS3231 component - which should also apply to DS3232 - I'll upload the latest version - which now supports SQW - here : https://www.matrixtsl.com/mmforums/viewtopic.php?f=80&t=22188 It's by no means complete yet - it's not a component yet, and I...

The DS3231 doesn't quite do what I'd hoped - alarm when running on battery backup. I may have to look at something like the MCP7940n - which seems able to do it. (The SQW does work on battery on the ds3231/2) General layout and details of control are similar though and the current FC component seems...

Not much interest... Still I made an alpha version. Seems to work well (with some provisos - alarms can be set, but not the sqw and 12h mode isn't really supported yet) It also isn't made into a component - so extraneous macros. On the plus side it works - demo main here sets a minute alarm on alarm...

I'm not usually in favour of re-inventing the wheel - but I noticed a comment about DS3231 alarms in the forum recently.. I alo wanted an interrupt using alarm 2 (hours and minutes match) - to wake a low power logger (so this can occur on the battery backup of the RTC and wake an ATTiny) (Note I use...

I wrote a program using UART on an Arduino Nano. I then modified it to run on an ATTiny85 - I didn't delete the UART code - it was only referenced in a macro that was not used - and I had intended to go and modify this later - to get the data logged out without using USB comms (using a 'bare' 85) Co...

Hi Martin, One query - there is some overlap in the checked values (<208 sw 1 >200 sw 2 for example)... This shouldn't pose a problem - button registered should map to first conditional statement... Unless you just use consecutive if's (and nested is going to get a bit messy for 9 switches) in which...

Thanks Martin,

An excellent resource - much neater than multiplexing the switches...

Martin

Having recently purchased and then written code to access 1MBit flash memory (also available as 2 and 4MBit chips) ( SST39SF010A) It struck me that that it might be 'fun' to have a large memory available to smaller MCUs with less pins.. I had some 24LC256 chips - so 4 would make a 1MBit memory (128K...

Hi Samtim,

You just need to save a 16 bit number - so first byte as (or Value >> 8 )and second byte as (Note for the second byte you can just use as it will be 'truncated' to 8 bits or both of which are quicker than the modulus calculation..

Martin

Can you post your Flowcode so far?

If you would like to send me a sample of the chip in pdip format I would have a go - I have previously written a component for i2c memory chips...

Martin

Unfortunately - the flowcode component has the address 'hardcoded' in - have a look at the C code (for example SendCommand). For example in the case of SSD1306(i2c) - 120.... The actual address is only used in a few places (SendCommand for example) - so these could be modified to use a variable rath...

Yes, sorry my bad...

~ does give the expected results (0, 1) in the simulator if variable is of type bool..
But - it is a bitwise complement - so if the hardware is treating it as a byte (then it will be 0 - 255 or worse 1 - 254) on hardware...
So to avoid surprises use !


Martin

Try using ~ (tilde)
Where a is of type bool.

Should work

Martin

Re: Help with MQTT Read Postby mnf » Thu May 07, 2020 9:35 pm Hi James, welcome to the forums. Posting the same question again is frowned upon, however - (so I've deleted the copy) better to add another comment to the previous thread showing what you have tried and what has and hasn't worked.. Pleas...

A minor inconvenience - the input icon doesn't allow AN7 (Port C7) to be selected for input.

Pins a6 and a7 can only be used as analog inputs (so sadly my idea of using them to power a i2c eeprom didn't work)
A6 (c6) is allowed in input and output - but will only work as an input..

Martin

If space was at a premium then you could save the data as a bit stream - 7 bits would give you 0..127 and 4 bits 0..15. Seems like a lot of extra work however - why not just save one value per byte (use << 8 and >> 8 to access the upper byte of you need to convert to a 16 bit integer) - the SD routi...

Yes - some sites are less than friendly... Always seems a shame - everyone needs to learn something sometime.....


Martin