AXE033 Alarm

[Tony P]

I have set up an AXE033 LCD with clock upgrade.
I have been successful setting the time in both serial mode and i2c mode.
I can read the time in both modes using BCDTOASCII etc where necessary

My problem is using the alarm function in serial mode.
The manual states:

Main header (OUT)
The alarm output triggers (goes high for 5 seconds) whenever a clock alarm occurs.
The alarm output can sink or source 20mA.

There is also a diagram showing the OUT pin of the serial LCD connecting to an IN pin on a Picaxe chip (I am using an 18m2)
It also shows the code to set an alarm but does not show how to use the alarm output!

I am probably missing something really simple but I wish somebody could show me where!!

 

[Technical]

The alarm works in standalone 'alarm clock' mode only (ie when the clock jumper is fitted), not when you are using it in serial/i2c mode.

 

[Tony P]

So where the manual states that "The pulse output and alarm output operate as normal." when the clock jumper is attached does not actually mean that they work in any other way??

 

[Tony P]

Is there a way of using the LCD in serial mode and the clock upgrade in i2c mode?

I can set the time on the clock in serial mode and I can read the clock using SCL/SDA but the characters sometimes go a bit haywire

 

[nick12ab]

Is there a way of using the LCD in serial mode and the clock upgrade in i2c mode?

You would have to remove the DS1307 from the AXE033 PCB.

I can set the time on the clock in serial mode and I can read the clock using SCL/SDA but the characters sometimes go a bit haywire

That's because the AXE033 is also an i2c master when in serial mode so when you try to use a PICAXE as an i2c master sometimes both PICAXE and AXE033 will try to read data from the DS1307 at the same time then this happens.

 

[Digisapien]

Have you figured out how to convert to 12 hour format.

 

[Tony P]

Is it not as simple as:
if hour >12 then let hour = hour -12

 

[MartinM57]

..or maybe even
if hour >= 12 then let hour = hour - 12

 

[westaust55]

Or the solution posted today by hippy in post 3 here:
http://www.picaxeforum.co.uk/showthread.php?25554-Help-convert-24-hour-format-on-axe033-lcd-to-12-hour-format-clock

 

[Digisapien]

..or maybe even
if hour >= 12 then let hour = hour - 12

We'll just starting and working as an havoc tech 10 hrs a day. Hard to experiment. But I'll try that

 

[MartinM57]

You may want to think about the >= part a bit more...depends what you want to see on the clock around midday/midnight

For some reason, I associate seeing 00:45 as a preferred indication of "a quarter to one" in the middle of the night, but see 12:45 as a preferred indication for "a quarter to one" in the afternoon - which may or may not be a "12 hour clock"

Hippy's:
t12 = t24 Mod 12
If t12 = 0 Then : t12 = 12 : End If
..from the other thread will give you 12:45 for "a quarter to one" in both the middle of the night and the middle of the day