Can anybody help me with ATSHA204A interface?

Log in or register to post comments
Go To Last Post
4 posts / 0 new
Author
Message
Harikrishnan911
Harikrishnan911's picture
Level: Hangaround
Joined: Fri. Sep 9, 2016
Posts: 219 View posts
Location: Kerala, India
#1
Posted by Harikrishnan911: Sat. Mar 10, 2018 - 09:30 AM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi,

 

i am a newbie in this domain & i am facing this challenge to store data in ATSHA204A internal EEPROM with encryption enabled.

I have gone through the datasheet but didn't really understand with all those facts & info. I really need a helping hand here.

I have managed to wake up the crypto IC & was able to communicate with it.

Can this IC perform multiple read write to its EEPROM with causing any issues?

The Zone encoding pose another hurdle in this process.

Can somebody help me with this?

 

Thanks & Regards,

Silly beans are always silly
:)

Tags:

Security, General Security Discussions, #atsha204a, #SAMD21, Lighting Control
Top
PhillyNJ
PhillyNJ's picture
Level: Resident
Joined: Sat. Oct 11, 2014
Posts: 730 View posts
Posted by PhillyNJ: Sat. Oct 27, 2018 - 11:18 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Harikrishnan911 wrote:
Can this IC perform multiple read write to its EEPROM with causing any issues?

 

You should be able to read and write to this device after the configuration is locked depending on how the slots are configured. Here are the steps:

 

  1.     Configure the SlotConfigs, UseFlags and UpdateCount Config (AKA Config Zone)
  2.     Lock the Configuration Zone
  3.     Write your keys to the Slots (aka data zone)
  4.     Write to OTP Zone if required
  5.     Lock OTP and Data Zone

 

The SlotConfig controls how the keys are used and accessed. Depending on how you configure the slots, they can either never be read, allow clear text reads or allow encrypted reads. Writes to the ATSHA204a slots can be done if and only if the slot is configured for the DerivedKey command.

 

As for the Address and Zone encoding, I wrote a tutorial here  that may help you.

 

"When all else fails, read the directions"

Last Edited: Sat. Jun 8, 2019 - 11:20 PM
Top
NJ88
NJ88's picture
Level: New Member
Joined: Wed. Jun 9, 2021
Posts: 3 View posts
Posted by NJ88: Mon. Jun 14, 2021 - 02:26 AM (Reply to #2)
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi,Im newbiew. I would like to know if ATSHA204A can connect to any microcontroller? I want to connect with Attiny412. What else hardware and software component needed for this?

 

Charmed

Top
PhillyNJ
PhillyNJ's picture
Level: Resident
Joined: Sat. Oct 11, 2014
Posts: 730 View posts
Posted by PhillyNJ: Wed. Jun 30, 2021 - 11:25 PM (Reply to #3)
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

It should. The ATSHA2014 supports single wire and i2c. See http://ww1.microchip.com/downloads/en/DeviceDoc/ATSHA204A-Data-Sheet-40002025A.pdf

"When all else fails, read the directions"

Top