PiWalletSV

Welcome to PiWalletSV

Your air-gapped Bitcoin SV cold wallet —
keys on the Pi, chain on your phone.

Thank you for supporting an open, non-custodial signer built from off-the-shelf parts you can inspect and replace. This little computer holds your signing keys and never connects to Wi‑Fi, Bluetooth, or Ethernet. Your phone or laptop runs the companion app to watch the chain and build transactions — the Pi only signs what you approve on its screen.

Air-gapped by design Open source · MIT Round-one beta kit

Be patient at boot

First power-on can take 1–2 minutes before the logo appears — the display may stay dark while the system starts. Every boot after setup is faster. Don't panic; let it finish.

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Pi Zero W inside

Your kit uses a Raspberry Pi Zero W — the only Pi model we can source in meaningful quantity right now. It is slower than a desktop, but more than enough for signing and cold storage. Speed was never the goal; isolation was.

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You are the backup

Write your 12- or 24-word seed phrase on paper or steel. No company can recover lost seeds or PINs. Your funds always remain recoverable in any BIP39 wallet — PiWalletSV is not required.

Beta software — read before funding

PiWalletSV software is beta. It is fully functional with no currently known issues. Bugs will be fixed and released; all notices are posted on @PiWalletSV (x.com/PiWalletSV).

There is no warranty and no custodial recovery service. The bonnet walks you through a disclaimer on first boot; the full text is at piwalletsv.com/disclaimer

Firmware ________
Image ID ________

Quick start

piwalletsv.com
Companion: app.piwalletsv.com
Verify: github.com/mohrt/PiWalletSV/releases
Before you fund — verify the microSD (strongly recommended) Kits are boot-tested before shipment, so the card no longer byte-matches the pristine image checksum. Proper cold-wallet practice: verify the signed download on GitHub Releases and re-flash before creating a wallet or receiving funds.

First boot on the bonnet

Plug the included power cable into the right-most micro-USB port, then wait 1–2 minutes for the logo.

  1. Disclaimer — read all pages; hold A to accept.
  2. Vault PIN — 6 digits.
  3. Your first wallet — create (or restore) on the Pi; write every seed word offline. Keys stay on the device.
  4. Airgap check — Settings → Maintenance → Airgap status.
  5. Pair companion — open app.piwalletsv.com, then scan the Pi’s pairing QR to copy the xpub (watch-only; never the seed).
Wrong PIN 6× in a row wipes the vault on the device. Your seed phrase is the real backup — not the PIN, not support.

Controls & daily use

  • Joystick — move / change digits · A confirm · B back
  • B hold ~5 s on boot logo — factory diagnostics
  • From Wallets, press B → Settings
  • Receive — companion shows address; confirm on Pi for large amounts.
  • Send — companion builds tx → Pi scans QR → review → hold A → companion broadcasts.
  • Backup / upgrade — optional OTG + USB stick (left port) → Settings → Maintenance → USB backup, or restore from written seed.

Swap or re-flash microSD

Export vault to USB (optional OTG + stick) or confirm you have your seed phrase(s) before re-flashing.

Tweezers shortcut (recommended for re-imaging) Power off. Pull the microSD with a thin pair of tweezers through the case slot — no disassembly. Re-flash on your computer, then reinsert the same way.

Full service (hardware repair / if tweezers won’t reach):

  1. Power off — unplug and wait a few seconds.
  2. Open the case — corner screws; save the two button caps.
  3. Bonnet — remove its two screws; pry up gently a little at a time.
  4. Pi board — remove its two screws; lift gently (camera ribbon on the back).
  5. microSD — pull straight out (no spring latch).
  6. Computer — USB reader; verify and re-flash from GitHub Releases.
  7. Reassemble — card → Pi screws → bonnet screws → lid + button caps.
  8. Test before tightening — A, B, and joystick must click freely, then tighten corners.

Assembly

Your kit ships fully assembled. Use these only if you took it apart.

  1. Pi off. Seat the bonnet on the 40-pin header; replace its two screws.
  2. Camera ribbon → CSI (latch open → insert → latch closed).
  3. Insert the microSD (label side as printed on the Pi).
  4. Power into the right-most micro-USB port only.
USB ports Right-most — power only (included cable). Never plug a flash drive here. Left — optional vault USB backup (your OTG + stick); or restore from seed on the bonnet.

Do / Don't

Do Don't
Re-flash from signed download before mainnet funds Type your seed into a phone, laptop, or website
Store seed phrase separately from the device Connect the Pi to Wi‑Fi or plug a computer into USB
Check Airgap status after upgrades Share your PIN or seed with anyone — ever