Table of content

• Assignment
• My Work
• Group Assignment
• Boards production for AVR 1 series
• Connection and test
• Read datasheet
• Architecture
• Pinout
• Memories
• Programming
• Arduino (sample - t1614.button.ino)
• Arduino (t1614.button_blink.ino)
• C (t1614.simpleblink.c)
• Build .hex from C language program
• Files
• Lessons Learned
• References

This week, I made boards of UPDI programmar and FTDI serial interface for writing and testing my board with AVR 1 Series (that I made as ATtiny1614 echo board as an assignment outcome in week of electronics design). I created program by Arudino (.ino) language and C language, then compile, write and test program using my boards.

Compare the performance and development workflows for different microcontroller families(link )

In week of electronics design, I switched to ATtiny1614 echo board (AVR 1 series) and its UPDI programmer from ISP programmer. Accordingly, I started from making UPDI programmer(USB-FT230XS-UPDI), UPDI-FTDI converter and USB-FT230XS-serial converter. in this week.

milled PCB by Roland MDX-15 using mods.

Assembled(soldering) the boards.

ATtiny 1614 hello echo board

USB-FT230XS-Serial

FTDI-UPDI

USB-FT230XS-UPDI

At local session, the connection with my macbook pro did now work well. When I run ls /dev | grep -i usb, both of USB-FT230XS-UPDI(Programmer) and USB-FT230XS-Serial(Serial communication interface) were not listed.

Finally, it worked well after I came back to my home and renewed all the USB cables(that I bought in Amazon) and USB adapters(I bought at 100yen shop).

This is a way of a successful connection

USB Type C-A adapter - USB type A cable - USB-FT230XS-UPDI - Attiny1614 echo board - USB-FT230XS-Serial - USB type A cable - USB Type A-C adapter (host computer: Macbook pro)

$ ls /dev | grep -i usb
cu.usbserial-D307RG9Y (---USB-FT230XS-Serial)
cu.usbserial-D307RGA0 (---USB-FT230XS-UPDI)
tty.usbserial-D307RG9Y (---USB-FT230XS-Serial)
tty.usbserial-D307RGA0 (---USB-FT230XS-UPDI)

I have already written in detail about:

• How to build .hex file from .ino > here
• How to write program from linux > here
• How to write program from mac > here

Though I wanted to write a progarm by the same procedure to the same board, following errors occurred time by time:

• Exception: Failed to enter NVM programming mode
• Exception: Failed to chip erase using key
• Exception: Incorrect echo data

    ZTOKLIC02Z93YHLVDL:build tatsuro.homma$ pyupdi.py -d tiny1614 -c /dev/tty.usbserial-D307RGA0 -b 57600 -f hello.t1614.echo.ino.hex
    Device is locked. Performing unlock with chip erase.
    Traceback (most recent call last):
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 98, in _main
        nvm.enter_progmode()
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/nvm.py", line 34, in enter_progmode
        if self.application.enter_progmode():
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/application.py", line 129, in enter_progmode
        raise Exception("Failed to enter NVM programming mode")
    Exception: Failed to enter NVM programming mode
    
    During handling of the above exception, another exception occurred:
    
    Traceback (most recent call last):
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 178, in 
        _main()
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 101, in _main
        nvm.unlock_device()
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/nvm.py", line 54, in unlock_device
        self.application.unlock()
      File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/application.py", line 89, in unlock
        raise Exception("Failed to chip erase using key")
    Exception: Failed to chip erase using key

      $ pyupdi.py -d tiny1614 -c /dev/tty.usbserial-D307RGA0 -b 57600 -f hello.t1614.echo.ino.hex
      Device is locked. Performing unlock with chip erase.
      Traceback (most recent call last):
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 98, in _main
          nvm.enter_progmode()
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/nvm.py", line 34, in enter_progmode
          if self.application.enter_progmode():
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/application.py", line 129, in enter_progmode
          raise Exception("Failed to enter NVM programming mode")
      Exception: Failed to enter NVM programming mode
      
      During handling of the above exception, another exception occurred:
      
      Traceback (most recent call last):
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 178, in 
          _main()
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/bin/pyupdi.py", line 101, in _main
          nvm.unlock_device()
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/nvm.py", line 54, in unlock_device
          self.application.unlock()
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/application.py", line 81, in unlock
          self._progmode_key()
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/application.py", line 103, in _progmode_key
          self.datalink.key(constants.UPDI_KEY_64, constants.UPDI_KEY_NVM)
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/link.py", line 215, in key
          self.updi_phy.send(list(reversed(list(key))))
        File "/Users/tatsuro.homma/.pyenv/versions/3.7.0/lib/python3.7/site-packages/updi/physical.py", line 85, in send
          raise Exception("Incorrect echo data")
      Exception: Incorrect echo data 

Seeing a issue thread in pyupdi github, these issue comes from power supply for target board via serial port of FTDI. So, I tried to put the USB cable to my room's quick battery charger port of 2.4A. Then this resolution works!

Stable environment for embedded programming

(In my case) it's important to have adapters and cables with strong joint. Also, it's necessary to sufficient power supply to the target board.

TBD: Check the power supply cases1: supply from USB type-C port in my macbook pro and case2: supply from 2.4A of quick charger for USB.

I read the AVR ATtiny1614 datasheet and picked information that I'm interested in.

Architecture

Overview of tinyAVR 1-series is laying out memory sizes and pin count variant.

Refs: 2. tinyAVR 1-serires overview

ATtiny1614 has 16KB Flash memories and 14 pins.

Refs: 3. Block Diagram

Refs: 8. AVR CPU - 8.3 Architecture

"In order to maximize performance and parallelism, the AVR CPU uses a Harvard architecture with separate buses for program and data. Instructions in the program memory are executed with single-level pipelining. While one instruction is being executed, the next instruction is prefetched from the program memory. This enables instructions to be executed on every clock cycle."

Pinout

Refs: 4.1 14-Pin SOIC

Besides datasheet description, magaTinyCore's pin mapping is visualized at the following diagrams on the website of SpenceKonde(SpenceKonde/megaTinyCore(ATtiny_x14.md),

Memories

Refs: 6. Memories (6.1 Overview, 6.2 Memory Map)

• ERPROM: 256bytes
• SRAM: 2KB
• Flash: 16KB

Flash has three sections(boot, application code and application data) for write protection.

Programming - Arduino (Sample: t1614.button.ino)

According to Pinout spec in datasheet,

• My LED connected PA7 of ATtiny1614, which is Arduino Pin 3
• My Switch connected PA4 of ATtiny1614, which is Arduino Pin 0

The deatil procedure is written in week06 document here(How to build .hex file from .ino)

When setting the board as ATtiny1614, we cannot edit the .ino file in Arduino IDE. So you need to open .ino file by text editor.

Besides that, .ino file needs to be a directory with the same name as .ino - like "t1614.button/t1614.button.ino"

source file is ATtiny1614.button.ino

Programming - Arduino (t1614.button_blink.ino: blink and serial communication)

I tried to write a program to press button triggers toggling the frequency of blink

My idea is that 3 seconds of long push on the button triggers the change of frequency of blink in 4 status: 0: Nothing, 1: 100msec, 2:500msec, 3:1000msec. The status is sent to serial monitor.

Source code - Attiny1614.button_blink.ino

source file is ATtiny1614.button_blink.ino

Programming - C (t1614.simpleblink.c)

It took time for me to dig in how to read datasheet of AVR 1 Series( to write a program and compile it into .hex file

Firstly, I tried to write a code based on echo.c for Attiny44. However it went wrong as the usage of register for In-Out pins are different between tiny44 and tiny1614(AVR 1 series). Based on little information for AVR 1 serires implementation, I managed to obtain a simple blink output sample source in a discussion forum. Then I added input pin setting and function to read status from button.

Tips

Datasheet of ATtiny1614 tells something.

For accessing pin, it's necessary to access via port instance(e.g. PORTA)

Input data can be derived from "IN" register.

If "DIR" is set to 1, the assigned pin is used as output pin.

There are various function in register. For example, OUTTGL will toggle the corresponding bit in PORT.OUT.

Source code - Attiny1614.simpleblink.c

Build .hex file from C language program

As Arduino IDE cannot open .c source file, I tried to compile it by arduino-cli commandline tool.

What I did is:

1. Install arduino-cli via homebrew
2. Make configuration file
3. Install a board of ATtiny1614
4. Add 3rd party board manager
5. Compile
6. Write program by pyupdi

Refs: Arduino-cli

Port                            Type              Board Name FQBN Core
/dev/cu.Bluetooth-Incoming-Port Serial Port       Unknown             
/dev/cu.Kn-iphone-WirelessiAP   Serial Port       Unknown             
/dev/cu.usbserial-D307RG9Y      Serial Port (USB) Unknown             
/dev/cu.usbserial-D307RGA0      Serial Port (USB) Unknown   

            Board Name                                         FQBN                            
ATtiny1614/1604/814/804/414/404/214/204            megaTinyCore:megaavr:atxy4      
ATtiny1614/1604/814/804/414/404/214/204 (optiboot) megaTinyCore:megaavr:atxy4o     
ATtiny1634 (No bootloader)                         ATTinyCore:avr:attiny1634       
ATtiny1634 (Optiboot)                              ATTinyCore:avr:attiny1634opti   
ATtiny167/87 (Optiboot)                            ATTinyCore:avr:attinyx7opti     
ATtiny2313/4313                                    ATTinyCore:avr:attinyx313       
ATtiny24/44/84                                     ATTinyCore:avr:attinyx4         
ATtiny25/45/85                                     ATTinyCore:avr:attinyx5         
ATtiny261/461/861                                  ATTinyCore:avr:attinyx61        
ATtiny3216/1616/1606/816/806/416/406               megaTinyCore:megaavr:atxy6      
ATtiny3216/1616/1606/816/806/416/406 (optiboot)    megaTinyCore:megaavr:atxy6o     
ATtiny3217/1617/1607/817/807/417                   megaTinyCore:megaavr:atxy7      
ATtiny3217/1617/1607/817/807/417 (Optiboot)        megaTinyCore:megaavr:atxy7o     
ATtiny412/402/212/202                              megaTinyCore:megaavr:atxy2      
ATtiny412/402/212/202 (optiboot)                   megaTinyCore:megaavr:atxy2o     
ATtiny43                                           ATTinyCore:avr:attiny43         
ATtiny44/84 (optiboot)                             ATTinyCore:avr:attinyx4opti     
ATtiny441/841 (No bootloader)                      ATTinyCore:avr:attinyx41        
ATtiny441/841 (Optiboot)                           ATTinyCore:avr:attinyx41opti    
ATtiny45/85 (Optiboot)                             ATTinyCore:avr:attinyx5opti     
ATtiny461/861 (optiboot)                           ATTinyCore:avr:attinyx61opti    
ATtiny48/88                                        ATTinyCore:avr:attinyx8         
ATtiny48/88 (optiboot)                             ATTinyCore:avr:attinyx8opti     
ATtiny828 (No bootloader)                          ATTinyCore:avr:attiny828        
ATtiny828 (Optiboot)                               ATTinyCore:avr:attiny828opti    
ATtiny87/167 (No bootloader)                       ATTinyCore:avr:attinyx7         
Attiny416 Xplained Nano (optiboot)                 megaTinyCore:megaavr:Xplained416
Attiny817 Xplained Mini (optiboot)                 megaTinyCore:megaavr:Xplained817

ID                   Installed Latest Name
ATTinyCore:avr       1.3.2     1.3.2      
esp32:esp32          1.0.4     1.0.4      
esp8266:esp8266      2.4.2     2.4.2      
megaTinyCore:megaavr 1.1.5     1.1.5

  board_manager:
    additional_urls:
      http://drazzy.com/package_drazzy.com_index.json

Updating index: package_index.json downloaded                                                                           
Updating index: package_drazzy.com_index.json downloaded  

$ arduino-cli core search ATtiny1614
ID                   Version Name        
megaTinyCore:megaavr 1.1.8   megaTinyCore