The two level priority interrupt is a step down from the 3 Level interrupt controller in the Xmegas, but is a big step up from a single level controller in the classic AVR Mega and Tiny micros.
Additionally to the CVT [Compact Vector Table] feature, the AVR Dx interrupt controller offers a non-maskable interrupt for critical functions, one selectable high-priority interrupt, and an optional round robin scheduling scheme for normal priority interrupts.
The AVR DA datasheet says that VDD and AVDD are internally connected. What's the point of L200 on AVDD on the AVR128DA48 CURIOSITY NANO if they are not going to do the same on VDD? Is this just cargo cult PCB design? Or does it really serve a purpose?
Maybe the AVDD domain is diode connected to the VDD domain. Consider the MVIO domain on the DB series; it is new to me, so I am mostly clueless, but the AVDD domain would probably need some changes to work like that. I don't even know if ADCs can be done like the MVIO stuff, but who knows? If so, I am confident Microchip will get it to us, but as someone will point out, I should not hold my breath.
I appreciate the guesses -- I can guess too -- but I need something a little more definitive.
Does anyone from Microchip ever provide definitive answers to questions like this here? For all its flaws, I can actually count on STMicro to provide useful support on their community forum when needed.
I measure 3.3 ohm resistance between VCC and AVCC in both directions with a multimeter on an AVR128DA28. This is the best I can do for you... this forum is made up mostly of users of AVRs, we didn't design them...
I measure 3.3 ohm resistance between VCC and AVCC in both directions with a multimeter on an AVR128DA28. This is the best I can do for you... this forum is made up mostly of users of AVRs, we didn't design them...
Thank you. That's quite helpful. And a bit disappointing for my use case.
Also wanted to point out that someone else asked where to find the Microchip support forum for AVR chips and was directed here: https://www.microchip.com/forums...
Interesting. I hadn't realized that the MVIO features would work with both VCCio > VCC AND VCCio < VCC, or that they had gone to such lengths to monitor and detect assorted separate VCCio failures...
I am finalizing a board with a DB that will run at 5V and interface to an R-Pi at 3V3 with the MVIO port. A previous setup (324pb) let out some smoke when I did not do the power-up sequence correctly; this MVIO seemed like a natural solution and should allow any power sequence to be valid.
via Dev Tool Deals | Microchip Technology
"Dare to be naïve." - Buckminster Fuller
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TopAVR DB :
AN3725 - Buck Converter Design and Feedback Controller Using Core Independent Peripherals
Buck Converter Design and Feedback Controller Using Core Independent Peripherals (web doc)
edit :
Switch Mode Power Supply - YouTube (8m51s)
"Dare to be naïve." - Buckminster Fuller
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Topin Migration from the megaAVR® to AVR® Dx Microcontroller Families
or AN3731 - Migration from the megaAVR to AVR Dx Microcontroller Families (PDF)
"Dare to be naïve." - Buckminster Fuller
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TopThe compact vector table is a nice feature for small memory AVRs.
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TopThe AVR DA datasheet says that VDD and AVDD are internally connected. What's the point of L200 on AVDD on the AVR128DA48 CURIOSITY NANO if they are not going to do the same on VDD? Is this just cargo cult PCB design? Or does it really serve a purpose?
Reference: http://ww1.microchip.com/downloa... , page 29 for schematic.
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TopAlthough internally connected, there may be some impedance between VDD and AVDD that is not stated.
Providing external isolation between the analog and digital domains may improve the noise on those circuits when using analog signals.
(Or the inductor could just be a cut and paste from earlier designs...)
David
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TopMaybe the AVDD domain is diode connected to the VDD domain. Consider the MVIO domain on the DB series; it is new to me, so I am mostly clueless, but the AVDD domain would probably need some changes to work like that. I don't even know if ADCs can be done like the MVIO stuff, but who knows? If so, I am confident Microchip will get it to us, but as someone will point out, I should not hold my breath.
my projects: https://github.com/epccs
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TopI appreciate the guesses -- I can guess too -- but I need something a little more definitive.
Does anyone from Microchip ever provide definitive answers to questions like this here? For all its flaws, I can actually count on STMicro to provide useful support on their community forum when needed.
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TopI was not under the impression that this was Microchip support? It is more like a group of cranky old people that occasionally talk about AVRs.
https://www.microchip.com/en-us/support
https://microchipsupport.force.com/s/support-resources?tabName=Community
my projects: https://github.com/epccs
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TopIf you want an answer from Microchip you need to open a support question on their website.
Moderator
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TopGood to know.
I measure 3.3 ohm resistance between VCC and AVCC in both directions with a multimeter on an AVR128DA28. This is the best I can do for you... this forum is made up mostly of users of AVRs, we didn't design them...
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TopAtmel (now Microchip) points people here for support. This is how I ended up here looking for infomation on AVR DA parts.
https://community.atmel.com/
There is no support forums on Microchip's site dedicated to AVR chips. It's still very much PIC-land.
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TopThank you. That's quite helpful. And a bit disappointing for my use case.
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TopAlso wanted to point out that someone else asked where to find the Microchip support forum for AVR chips and was directed here: https://www.microchip.com/forums...
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Top"Dare to be naïve." - Buckminster Fuller
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TopTraining Getting Started with AVR® DB OPAMP, XOSHF and MVIO - Atmel Studio
Training Getting Started with AVR® DB OPAMP, XOSCHF and MVIO - MPLAB®
"Dare to be naïve." - Buckminster Fuller
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TopAVR128DA :
Silicon Errata and Data Sheet Clarification
AVR64DA :
Silicon Errata and Data Sheet Clarification
AVR32DA :
Silicon Errata and Data Sheet Clarification
"Dare to be naïve." - Buckminster Fuller
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TopUsing the MPLAB® Mindi™ Analog Simulator with the 8-Bit Operational Amplifier Module
"Dare to be naïve." - Buckminster Fuller
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TopMVIO is digital only
Multi-Voltage I/O (MVIO) on 8-bit Microcontrollers - YouTube (3m54s)
"Dare to be naïve." - Buckminster Fuller
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TopInteresting. I hadn't realized that the MVIO features would work with both VCCio > VCC AND VCCio < VCC, or that they had gone to such lengths to monitor and detect assorted separate VCCio failures...
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TopI am finalizing a board with a DB that will run at 5V and interface to an R-Pi at 3V3 with the MVIO port. A previous setup (324pb) let out some smoke when I did not do the power-up sequence correctly; this MVIO seemed like a natural solution and should allow any power sequence to be valid.
my projects: https://github.com/epccs
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TopWith DB line the MVIO fuse may
defaultbe factory programed to enabledhttps://github.com/SpenceKonde/DxCore/issues/45#issuecomment-742853995
That makes sense to me, but is it true?
my projects: https://github.com/epccs
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TopAVR DA added :
TB3229 Getting Started with GPIO
"Dare to be naïve." - Buckminster Fuller
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Topweb pages for the future AVR DD :
AVR64DD32 - 8-bit Microcontrollers
AVR64DD28 - 8-bit Microcontrollers
"Dare to be naïve." - Buckminster Fuller
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TopThose look very nice. I wish they had USB though. Maybe I'm the only one doing USB on 8 bit any more...
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