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Quazee137

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Joined: 07/08/2016
Location: United States
Posts: 600

Posted: 07:15am 28 Oct 2017

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I was using the SSD1306 I2C driver
and a few times I needed to start fresh
and when I did

library delete

a few times I got

CPU exception #10
In CFunction at address 0x9D00DF74
Processor restarted

or this

CPU exception #10
In CFunction at address 0x9D00E02C
Processor restarted

this is a well used chip so I tried
a few new ones same thing.

no problems using the driver.

just letting you know about it.

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10565

Posted: 07:39am 28 Oct 2017

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Quote a few times I got
CPU exception

This is a benign artifact of the way the driver works. When you output to the SSD1306 the program just updates a memory buffer. There is then a timer interrupt that runs that checks for any updates and does the actual change to the display.

When you delete the library depending on the timing the timer interrupt could fire but the code has gone

so you can get a range of errors at this point but a restart clears it all up.

Quazee137

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Joined: 07/08/2016
Location: United States
Posts: 600

Posted: 09:20am 28 Oct 2017

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Thanks good to hear its not a bug.

I am using the Mite to do 4-20mA to pulse and this
very tiny display is just right to show the 4-20mA
input and the divider and current pulse rate.

Any way around the reserved pin as I was going to use
I2C for RTC?

I set the RTC up in MM.startup before starting the driver
but cant make any other use of it to adjust the Mite time.

Aw as I typed it hit me use the output to interrupt me
once and hour and that should keep it in time. Or use
the 1Hz and keep a count for the hour.

Thanks for your work on all things MicroMite

Will be getting a few Hats when WW says they are ready.

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10565

Posted: 11:34am 28 Oct 2017

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Quote Any way around the reserved pin as I was going to use
I2C for RTC?

The ssd1306 driver can use any pins for SDA and SCK. They don't need to be the normal I2C pins. It uses a bit-banged I2C driver and not the PIC H/W

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2959

Posted: 11:56am 28 Oct 2017

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Quazee137 said Will be getting a few Hats when WW says they are ready.

Expecting several PCB designs to arrive from the factory by the end of this coming week. Included is the HAT Stand PCB. Will post here once ready to start shipping (hopefully next weekend)

Quazee137

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Joined: 07/08/2016
Location: United States
Posts: 600

Posted: 08:30am 31 Oct 2017

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Thanks I wasn't looking as I saw that they hooked right up to
mick's backpack and started playing.

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