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AVR128DA64/AVR64DA64

Pin Mapping / Pinout

DA64 Pin Mapping

Features and Peripherals

- AVR64DA64 AVR128DA64
Flash Memory 65536 131072
Flash Memory (With Optiboot) 65024 130560
SRAM 8192 16384
EEPROM 512 512
User Row 32 32
Max. Frequency (rated, MHz) 24 24
Clock Sources INT, EXT, XTAL INT, EXT, XTAL
Packages Available TQFP, VQFN TQFP, VQFN
Total pins on package 64 64
I/O Pins (not reset/UPDI) 54 54
Fully async pins 13 13
UPDI as I/O Pin No No
PWM capable I/O pins 46 50 45 50
Max simultaneous PWM outputs 19: 12+2+5 19: 12+2+5
16-bit Type A Timers - pins ea 2: 42, 18 2: 42, 18 9
16-bit Type B Timers, (pins) 5: 10 5: 10
12-bit Type D pins 4 16 4 16
USART (pin mappings) 6: all 2 6: all 2
SPI (pin mappings) 2: 3/3 2: 3/3
TWI/I2C (pin mappings) 2: 3/3 2: 3/3
12-bit ADC input pins 22 22
Of those, neg. diff. inputs 16 16
10-bit DAC 1 1
Analog Comparator (AC) 3 3
Zero-Cross Detectors (ZCD) 3 3
Custom Logic Blocks (LUTs) 6 6
Event System channels (out pins) 10: 13 10: 13 11
On-chip opamps (OPAMP) - -
MVIO, pins No No
Flash Endurance 1k 10k 1k 10k
LED_BUILTIN (and optiboot led) PIN_PA7 PIN_PA7

* As with all Dx-series, the flash didn't live up to expectations at extreme conditions. 1k is the worst case rating though, and under typical conditions, it is believed that the endurance is >= 10k cycles. I do not know how far along Microchip is in developing a solution, but it's being treated as datasheet clarification, so that's not encouraging. I am hoping for additional information on how flash endurance is influenced by various factors.

DA64 - the baseline 64-pin Dx-series part

No MVIO, No OPAMPS. 64-pins gets the last USART, ZCD, and TCB, plus an extra pinset for each SPI port, and 2 for TWI1. This is a much smaller step-change than 32-48, though peripheral density remains high by historical standards. There is no 32k flash version. The 128k version is afflicted particularly badly by errata.

Fully async pins

Pins 2 and 6 within each port are "fully async" and can respond to events shorter than 1 clock cycle, and can wake the chip on RISING or FALLING edges, not just LOW_LEVEL and CHANGE. The rest are "partially async" and can only respond to "low level" or "change" if there is no system clock running (all interrupt triggers will work if the I/O clock is running due to an RUNSTBY that requests it or because you are only in idle sleep mode).

USART mux options

All TX RX XDIR XCK
DEFAULT Px0 Px1 Px2 Px3
ALT1 Px4 Px5 Px6 Px7

Px refers to a port:

USART PORT
0 PORTA
1 PORTC
2 PORTF
3 PORTB
4 PORTE
5 PORTG

SPI mux options

SPI Swap name MOSI MISO SCK SS
SPI0 DEFAULT SPI0_SWAP0 PA4 PA5 PA6 PA7
SPI0 ALT1 SPI0_SWAP1 PE0 PE1 PE2 PE3
SPI0 ALT2 SPI0_SWAP2 PG4 PG5 PG6 PG7
SPI1 DEFAULT SPI1_SWAP0 PC0 PC1 PC2 PC3
SPI1 ALT1 SPI1_SWAP1 PC4 PC5 PC6 PC7
SPI1 ALT2 SPI1_SWAP2 PB4 PB5 PB6 PB7

The SPI library only makes one SPIClass object available (see The SPI.h library documentation for details).

TWI0 mux options

Mapping swap Master or Slave Dual Mode Slave
DEFAULT 0 SDA/PA2 SCL/PA3 SDA/PC2 SCL/PC3
ALT1 1 SDA/PA2 SCL/PA3 SDA/PC6 SCL/PC6
ALT2 2 SDA/PC2 SCL/PC3 SDA/PC7 SCL/PC7

TWI1 mux options

Mapping swap Master or Slave Dual Mode Slave
DEFAULT 0 SDA/PF2 SCL/PF3 SDA/PB2 SCL/PB3
ALT1 1 SDA/PF2 SCL/PF3 SDA/PB6 SCL/PB7
ALT2 2 SDA/PB2 SCL/PB3 SDA/PB6 SCL/PB7

PWM Pins

48-pins is an exciting breakpoint for PWM: You get another half dozen PWM pins from the second TCA1!

  • TCA0 is by default set to PORTC. This is a decision I would have made differently had I owned a crystal ball during the design process; but by the time the DBs had arrived with MVIO on PORTC (hence a poor pick for default pins for PWM), the core had been released and we don't like to break backwards compatibility. It's not much of an issue now that you can trivially switch the ports at runtime. I now think that PORTG is the obvious right choice.
  • TCA1 is by default set to PORTB, the only port on which it can have 6 pins on 48-pin DA's
  • TCD0 is left at the default pins on PORTA, because they are the only ones that work.
  • The 4 type B timers are set for PF4, PF5, PC0 and PC1, and this cannot be changed at runtime. Note that the millis timer cannot be used to generate PWM. TCB2 is the default millis timer, though this can be changed from the tools menu.
  • This gives 6 + 6 + 2 + 5 = 19 PWM channels simultaneously outputting PWM. 42/54 pins (78%) can output PWM from TCA0, and 9 or 18 (16.7 or 33.3%) from TCA1, with 8 or 16 (14.8% or 29.6%) having two TCA options.

TCA mux options

The Type A timers (TCA0 and TCA1) can be mapped to different pins as a group only, and analogWrite() is PORTMUX-aware - you can set TCA0 to output on any port's pin 0-5, and TCA1 to PORTB. Using this feature is easy - but not quite as trivial as other parts, since there are two bitfields. You simply write to the portmux register PORTMUX.TCAROUTEA = (TCA1 pinset << 3) | (TCA0 pinset) and then analogWrite() normally. TCA0 pinset is the port number (0-5 for ports A-F), TCA1 pinsets are from the table below, with numeric values of 0x00, 0x08, 0x10 and 0x18 (It is recommended to use the named constants however, as shown in the example).

TCA0 WO0 WO1 WO2 WO3 WO4 WO5
PORTA PA0 PA1 PA2 PA3 PA4 PA5
PORTB PB0 PB1 PB2 PB3 PB4 PB5
PORTC PC0 PC1 PC2 PC3 PC4 PC5
PORTD PD0 PD1 PD2 PD3 PD4 PD5
PORTE PE0 PE1 PE2 PE3 PE4 PE5
PORTF PF0 PF1 PF2 PF3 PF4 PF5
PORTG PG0 PG1 PG2 PG3 PG4 PG5
TCA1 WO0 WO1 WO2 WO3 WO4 WO5
PORTB PB0 PB1 PB2 PB3 PB4 PB5
PORTC PC4 PC5 PC6 - - -
PORTE PC4 PC5 PC6 - - -
PORTG PG0 PG1 PG2 PG3 PG4 PG5

The PORTG and PORTE mux options are not available on the AVR128DA64 due to errata, this erratum is not listed for 128DB or 64DA/DB parts. This was part of a pair of errata specific to the 128k 64-pin parts which betrayed the fact that the most testing and development was done on the 48-pin parts: both of these busted mux options are present only on 64-pin parts; the other errata was that the event system on wasn't connected to PB6/7 or PE4-7. That is, they forgot to add the connections to the pins that weren't used on the 48-pin parts). These were both corrected almost immediately internally - and did not impact any of the subsequent parts (128DA was the first Dx-family). Though two, possibly three die revs of the DA-series exist, one of which appeared some time after the initial release and well after parts where this was fixed had been shipping, none of these revisions corrected any of the known errata. It would be interesting to decap a DA Rev A6, A7, and A8. Even with crude methods, a major change to the fab process used (maybe a die shrink) would be apparent from differences in the size and color (the shiny colored surface of the die is a product of the microscopic structure) of the die.

If one found that A8 dice were smaller or a different color - okay, A8 was just a die shrink. If there were NOT such changes, one wonders what the difference between the die revs is - my mind would immediately turn to the possibility that there was some secret bug that was both very simple to fix, and didn't involve touching the buggy parts of the chip. I received some AVR128DA64's in mid 2023, and I expect that they will be A8's. I suspect that "gross process differences" like a die shrink could be detected by setting a CCL to invert it's own output with no synchronization and output to a pin, which is what I plan to do. This results in a MUCH higher frequency oscillation than the system clock, and involves behavior which is not constrained by the specs other than that that we know it's fast, because async things are described as potentially being shorter than a clock cycle and still detected.

It is strongly recommended to not have any PWM output enabled involving either the timer being moved nor the pins it is being moved to when setting PORTMUX.TCAROUTEA. In the latter case, you will not be able to turn off the existing PWM through the API functions.

PORTMUX.TCAROUTEA = PORTMUX_TCA0_PORTF_gc | PORTMUX_TCA1_PORTB_gc; // PWM on PORTF and PORTB pins 0-5
PORTMUX.TCAROUTEA = (PORTMUX.TCAROUTEA & PORTMUX_TCA1_gm) | PORTMUX_TCA0_PORTD_gc; // Move TCA0 PWM to PORTD but don't change TCA0
// The first option is slightly faster, as it isn't a read-modify-write. You almost always want TCA1 mux to be set to PORTB on a 128k parts
// Note that PORTMUX_TCA0_PORTA_gc and PORTMUX_TCA1_PORTB_gc have a numeric value of 0. So for the common case, you can use simple assignment to set
// PORTMUX.TCAROUTEA to PA, PB, PC, PD, PE, or PF.
// If you know what the other option is, it's more efficient to use the first construction (3 words of flash, 3 clocks) than the second (6 words, 7 clocks).

TCB mux options

TCBn Default Alt
TCB0 PA2 PF4
TCB1 PA3 PF5
TCB2 PC0 PB4
TCB3 PB5 PC1
TCB4 PG3 PC6

These are NOT PORTMUX-aware. Only the bold pin can be used without modifying or creating a new variant file. TCAs take priority over TCBs, so without changing the TCA0 mapping, TCB2/TCB3 are not used.

The type B timers are much better utility timers than PWM timers. TCB2 is the default millis timer and cannot be used for PWM in that mode. This configuration is recommended. See the Timer Reference for more information

TCD0 mux options

TCD0 WOA WOB WOC WOD
DEFAULT PA4 PA5 PA6 PA7
ALT1 PB4 PB5 PB6 PB7
ALT2 PF0 PF1 PF2 PF3
ALT1 PG4 PG5 PG6 PG7

The Type D timer, TCD0, has 2 output channels (WOA and WOB) and 4 output pins (WOA, WOB, WOC, and WOD). The hardware permits WOC and WOD to each output either WOA or WOB, but this added too much complexity to analogWrite; WOA and WOC output WOA, and WOD and WOB output WOB. Calling analogWrite() on either pin will enable it, calling digitalWrite() on that pin will turn the PWM off. Calling analogWrite() on WOC while already outputting on the WOA pin will result in both pins outputting the new duty cycle. Call digital write on first pin if this is not what you want. The datasheet describes TCD0 output on PA4-7, PB4-7, PF0-3, and PG4-7. What the datasheet giveth, the errata taketh away: the alternate pin options are hopelessly broken currently, only PA4-7 work.

LED_BUILTIN

Following precedent set by MegaCoreX, we declare that pin 7 - PIN_PA7 shall be the pin that the core "expects" to be connected to an LED. LED_BUILTIN is defined as that pin, and the bootloader will set that pin as output and try to blink the LED. Note that if the bootloader is not used, and your sketch does not reference LED_BUILTIN this pin is not otherwise treated any differently. If you want to have a different pin be recognized by the application (this does not change the bootloader - you would still need to do a custom build of that too), this can be overridden if a custom board definition is created by passing -DLED_BUILTIN=(some other pin) as part of build_extra_flags, building via the CLI, or by equivslent means provided by other third party development environments.

Reset pin can be input

Reset (PF6) can be set to work as an input (but never an output). The UPDI pin cannot be configured as an I/O pin.

ADC pins in differential mode

Only pins on PORTD and PORTE can be used as the negative side of a differential analog reading (analogReadDiff(), see Analog Reference). Pins on PORTF can be used as positive or single ended ADC inputs only.

Official Documentation

When all else fails, read the real documentation. They keep moving the .pdf files around, so now I just link to the prduct page, from whence the datasheet, errata, and "technical briefs".

Datasheets and errata change. You can sign up to get emails about such changes through the Microchip PCN system; if you don't, be sure to always use the latest version of the datasheet and especially the errata

At a minimum, everyone using a modern AVR should plan on having a PDF viewer open with the datasheet, and a text editor with a good search function and the ioavr______.h file open so that when you're trying to use a constant, but the compiler says it isn't declared/defined, you can search the io header for a key phrase in the constant and figure out how it was spelled/formatted or copy/paste it to your sketch. (see the IO headers for more information and links to them. I also keep the AVR instruction set manual open in the PDF viewer as well as the silicon errata and datasheet clarification. Datasheet clarifications are a bigger deal than an erratum, usually. An erratum says "Okay, this doesn't work, but it will some day, maybe" while a datasheet clarification says "This would be an errata, but we're not even going to pretend that we'll fix it some day". But watch out - datasheet clarifications vanish from the list once the datasheet has been updated!

The "silicon errata and datasheet clarification" is an extremely important document, particularly for parts like the DA with lots of errata. This document details lists and gives a terse description of ways in which they know that the hardware they are shipping does not behave as the datasheet describes. Both phrases are euphemisms. "Silicon Errata" are bugs in the hardware, which the manufacturer admits and agrees are incorrect behavior, and comes with a rarely fulfulled promise of a silicon revision to correct them. A "workaround" which may or may not be useful may by listed, or they may say "None". The workaround line may or may not be an accurate mirror on reality. For example, a "This feature does not work" erratum might have "Workaround: Do not use this feature" (not much of a workaround). But - for once - this goes both ways. An erratum listed as having no workaround occasionally in fact has a workaround. On he DA and DB, whichever pin the ADC is pointed at has it's digital input buffer disabled. All you need to to to work around that is set the ADC mux to point to something that's not a pin except when using it (that's what we do). I suspect a tunnel vision effect is in evidence here - in that example, I suspect that the problem was noticed in the context of trying to read the digital value of the pin while analog measurement was ongoing, so engineering was not thinking "Why the hell would anyone do that?!" but "Gee, yeah, there's no way you could do that", and nobody realized that there's a far more common case: the ADC is enabled, but not in use, and you may be doing other things with the pin.

That's the silicon errata part. Now the "datasheet clarification"? They are also usually silicon bugs (though a few are literal clarifications, or "clarifications" as in "we updated that, but forgot to tell documentation") - the Dx-series TCA Edge bit seems to have been such a case. The key difference between a silicon bug treated as an erratum and one treated with a datasheet clarifications is that an erratum indicates that the intended fix involves changing the die, while Datasheet Clarification involves changing the datasheet to say that the current behavior is correct. Datasheet clarifications sometimes downgrade specs significantly (like flash endurance under pessimal conditions, for example). And Datasheet Clarifications disappear from the errata when incorporated into the datasheet, so making certain to have matching versions of the datasheet and errata is essential.

The "Technical Briefs" are somewhat inconsistent in their value, but some are quite good.