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iDryerRP2040 Port Configuration

Where to configure

MENU -> GLOBAL -> PORT CONFIG

  • PORT 1
  • PORT 2
  • PORT 3

Mode values:

  • 0 = EXT — additional dryer module
  • 1 = SCR — screen
  • 2 = SCL — scales (HX711)
  • 3 = LNK — Link (UART: WiFi/Touch/portal)

Default configuration

For initial setup and wiring, it is convenient to use the default baseline configuration:

  • U4 (PORT 3) -> SCR — screen
  • U3 (PORT 2) -> LNK — Link
  • U2 (PORT 1) -> SCL — scales

It is important to understand the naming:

  • U2, U3, U4 are the connector labels on the enclosure/board that the user sees during wiring.
  • PORT 1, PORT 2, PORT 3 are the internal port names used in the firmware menu and in the documentation.

The mapping is:

  • U2 = PORT 1
  • U3 = PORT 2
  • U4 = PORT 3

This configuration is used as the basic starting layout:

  • Link is usually connected to U3 (PORT 2), and this is enough for initial device setup and portal access.
  • A screen on U4 (PORT 3) is useful for local control, but it is not required when Link is used.
  • Scales on U2 (PORT 1) are also optional and should be connected only if needed.

Important behavior

Changing PORT CONFIG does not switch hardware roles instantly.

Firmware snapshots port configuration at startup, and runtime works from that snapshot until the next reboot.

Result: after changing PORT CONFIG, reboot the device.

Code-level constraints

Validation in UI and port logic allows only the following rules:

  1. PORT 1: only EXT or SCL.
  2. PORT 2: only EXT, SCL, or LNK.
  3. PORT 3: only SCR or LNK.
  4. Roles SCR, SCL, LNK are unique (only one port can have each role).
  5. PORT 2 = EXT is allowed only if PORT 1 = EXT.

All valid combinations

Below is the full list of valid configurations that match current rules.

# PORT 1 PORT 2 PORT 3 Screen Link Scales Max UNITS
1 EXT EXT SCR Yes No No 3
2 EXT SCL SCR Yes No Port2 2
3 EXT LNK SCR Yes Port2 No 2
4 SCL LNK SCR Yes Port2 Port1 1
5 EXT EXT LNK No Port3 No 3
6 EXT SCL LNK No Port3 Port2 2

UNITS note:

  • UNITS is derived from the EXT chain:
  • base is always 1 (built-in module);
  • if PORT1=EXT -> up to 2;
  • if PORT2=EXT as well -> up to 3.

Practical meaning

  • If you need a local screen, PORT 3 must be SCR.
  • If Link is on PORT 3, screen is unavailable on that port.
  • Scales can be connected only where the port mode is SCL (Port1 or Port2).
  • Invalid combinations are usually blocked in UI during editing.

  1. Screen + Link + 1 module + scales PORT1=SCL, PORT2=LNK, PORT3=SCR (max UNITS=1).

  2. Screen + 2 modules + scales PORT1=EXT, PORT2=SCL, PORT3=SCR (max UNITS=2).

  3. No screen, Link-focused + 2 modules + scales PORT1=EXT, PORT2=SCL, PORT3=LNK (max UNITS=2).

  4. Maximum modules (3), no scales

  5. with screen: PORT1=EXT, PORT2=EXT, PORT3=SCR
  6. with Link: PORT1=EXT, PORT2=EXT, PORT3=LNK

If configuration is broken

If a non-working configuration was saved by mistake (mass module errors, menu lockup), use:

  • install.idryer.org -> Erase Firmware
  • then immediately Flash Firmware
  • then set correct PORT CONFIG again