The settings menu, contains a number of items which are essentially preferences.
Most people will use the Coldcard very briefly to authorize a transaction and put it away. They are not typically used for long. Therefore, we provide an "idle timeout" feature, set to a default time of four hours. You may change this to a number of different values between two minutes and eight hours, or disable the idle auto-logout function completely.
As a defensive measure, the "login countdown" can force a time delay when logging into the Coldcard. Once enabled, you must enter your PIN correctly, and then wait out a forced delay (of minutes/hours/days) while a count down is shown on-screen. Then enter your PIN correctly, a second time, to get in.
You can choose between 5/15/30 minutes, 1/2/4/8/12 hours, and 1/2/3/7/28 days. You must provide continuous power to the Coldcard during the entire period, so plan ahead and consider using an AC power source, charging a battery pack, or a UPS system.
If your plan is to operate exclusively in "air-gapped" mode, you may disable the USB port using this setting. The effect is immediate.
(new in v4.0.2)
The transaction is being signed by Coldcard typically includes a small "network fee" that goes to the miner who includes your transaction into a block. Normally, this fee is a tiny amount compared the the value of transaction, so the Coldcard will always warn if it exceeds 1% of the output value. There is also a hard limit on the fee, which defaults to 10%. If that threshold is exceeded, Coldcard will refuse to sign the transaction.
Using this new setting, you can change or remove that percentage fee limit. The 1% warning is still shown, but you will be able to approve the transaction as normal.
This sub-menu allows you to manage the multisig wallets known to the Coldcard.
You can give your Coldcard a personalized name. Once set, it will show this name immediately on power-up. No PIN is needed. Just press any key to proceed to the normal login process.
If this is enabled, when entering PIN, the order of the key numbers are randomized, so that cameras and shoulder-surfers are defeated.
From this menu, choose which blockchain to use. This does not affect your seed or master private key, but it does affect how we show payment addresses. Only developers and other users of TestNet will need this.
The duress wallet is intended as a personal safety feature: you should put money you are willing to lose into the duress wallet, and should you even be forced to reveal a PIN, you may provide the duress PIN in place of the "real" PIN. The Coldcard operates as normal when unlocked by the duress PIN code so that your attackers are not alerted. However, if they are technical enough, there are ways to detect the difference.
Start here to learn more about the technical details.
There is also a PIN number which we call the "brickme PIN". If that PIN code is used at any prompt, the Coldcard destroys itself. It becomes a useless brick. All the secrets are destroyed.
Please be careful with the brickme PIN. The destruction process is quick and irreversible. The Coldcard should be discarded as e-waste and cannot be reused.
If you've forgotten your PIN, we cannot help you. Even if you gave us the Coldcard, and we put all our resources into it, we cannot crack or break the Coldcard to get the seed out without the PIN. Our design uses a specialized key storage chip and your wallet secret (seed) is effectively encrypted by the PIN and held in that chip.
The number pad uses capacitive touch technology. From this setting menu, you may adjust the sensitivity of the touch. In warm or humid environments, or in cases where you see "phantom presses", choose "-2 Sensitive" (least sensitive). For the impatient, there is "+2 Sensitive" which feels more responsive and "quick".
The latest version of the firmware includes as many as five different levels of sensitivity. Please note that less-sensitive modes are a little slower to respond to your touch.
(new in v1.1.0, removed on Mk2 hardware)
In earlier makes of the Coldcard, there was a concept of a "secondary" wallet, that had most of the features of the main wallet, but an independany PIN code and seed phrase. Due to hardware limitations and security-related changes, this was removed in the Mk3 Coldcard.
(removed after Mk2)