Command Reference

pcu-cli is the command-line tool for reading and configuring In-CarPC vehicle PCs. This page lists every command that ships in the release build, with the exact output each one produces. For flags, JSON output, and scripting, see Scripting and Automation.

Running pcu-cli

Run a command as pcu-cli <command>. Hardware commands need elevated access:

• Windows: run status, ign, and dio from an elevated (Administrator) terminal. help, version, and driver work without elevation. Without Administrator rights, a hardware command stops with a terse error:

  ERROR: This program must be run as Administrator.
  Hardware access requires elevated privileges (PawnIO kernel driver).

• Linux: run with sudo, or set up unprivileged access once with pcu-setup.sh. See Install on Linux. SMBus platforms (CQ20 and CQ40N series) use the i2c group; port-I/O platforms (CQ40 series) need CAP_SYS_RAWIO.

Run with no arguments to open an interactive numbered menu, which is handy when launching by double-click:

$ pcu-cli
Commands:
  [1] Status        All available readings
  [2] Ignition      Timer configuration
  [3] Digital I/O   DI/DO read and control
  [4] Driver        PawnIO driver management
  [h] Help          Show CLI usage
  [0] Exit

Select:

A short banner is printed above the menu. The [4] Driver entry appears on Windows only. Passing flags but no command (for example pcu-cli --json) runs status.

The [2] Ignition sub-menu offers viewing the timer summary, setting a timer, and [3] Delay unit (minutes or seconds, where supported).

Help and the menu match your machine

pcu-cli help and the interactive menu adapt to the machine they are run on. On hardware pcu recognises, they list only what that platform actually has:

• help prints a Detected platform: line naming the machine, then only that platform’s commands and only its timer table.
• The menu hides the entries that do not apply. [2] Ignition does not appear on a CQ40 series machine; [3] Digital I/O does not appear on a CQ20 or CQ40N series machine.
• On Linux, the Requires: footer prints only the line that applies: the i2c group note on an SMBus machine, the CAP_SYS_RAWIO note on a port-I/O machine.

The menu numbers do not shift when an entry is hidden, so you will see gaps. That is deliberate: a number means the same thing on every machine, and any guide or note that refers to [3] stays correct.

Detection reads the board identity the BIOS reports. It needs no driver, no elevation, and no hardware access, so pcu-cli help gives you the tailored list even from an ordinary terminal.

Hiding is cosmetic only

A command that is hidden is not disabled. Typing it, or typing a hidden menu number, still runs it and still gets the normal “feature not available” answer with exit code 2. Nothing changes about what the hardware can do; only the reference list gets shorter.

On a machine pcu does not recognise, such as a development PC, nothing is hidden and the full command list and every platform’s timer table are shown. That is also what the examples on this page show, so you can see the whole surface in one place.

status

Read-only overview of the connected hardware. On a platform with ignition timers this includes the MCU identity and the timer summary.

Command	Description
pcu-cli status	Show platform, MCU identity, and all current hardware readings.

$ pcu-cli status
pcu v1.1.0  - In-CarPC CQ20 Status
----------------------------------------
  Platform            : In-CarPC CQ20 (Intel Atom x6425E)
  MCU Identity        : CQ20 MCU
  Hardware Rev        : DTB-IGN-MCU VER:10
  Firmware            : 12

  MCU Firmware        : 12
  Ignition Mode       : On
  Anti-Crank Delay    : 6s           anti-crank filter before DC power
  Boot Delay          : 4s           DC rails stable before power button
  Shutdown Delay      : 5m           IGN off to ACPI shutdown command
  Force Off Timeout   : 2m           hard power cut if OS hangs

The firmware version appears twice: once in the platform block and again in the MCU readings. That is expected.

ign

Read and write the ignition power-sequencing timers. Available on platforms with an ignition MCU: the CQ20 and the CQ40N series. The timer names, how many there are, and the unit they are counted in all come from the connected platform, so ign on a CQ20 lists four seconds-based timers and on a CQ40N lists five.

Older models: use CQUtils for now

pcu is new, and we are still backporting support for older In-CarPC models, including ignition management. More models will be supported soon. If your machine is not yet supported, use the CQUtils program preinstalled on the desktop in the meantime. Not sure which applies to your machine? Contact In-CarPC support.

Command	Description
pcu-cli ign	Show all ignition timer values.
pcu-cli ign get <timer>	Read one timer. Shorthand: pcu-cli ign <timer>.
pcu-cli ign set <timer> <value>	Write one timer in the platform’s unit (asks to confirm).
pcu-cli ign unit	Show the delay unit the timers are counted in (platforms with a selectable unit).
pcu-cli ign unit <minutes|seconds>	Change the delay unit (asks to confirm). Stored timer values are plain counts and are not converted.

The timer names differ by platform:

Platform	Timer names
In-CarPC CQ20	ign-on-delay, sw-on-delay, sw-off-delay, pw-off-delay
In-CarPC CQ40N series	ign-on-delay, ign-off-delay, pw-off-delay, ups-off-delay, ups-pw-off-delay

See Ignition Timers for each timer’s range, default, and what it controls.

$ pcu-cli ign
pcu v1.1.0  - In-CarPC CQ20 Ignition
----------------------------------------
  MCU Firmware        : 12
  Ignition Mode       : On
  Anti-Crank Delay    : 6s               IGN on to DC power
  Boot Delay          : 4s               DC on to power button
  Shutdown Delay      : 300s (5m)        IGN off to ACPI shutdown
  Force Off Timeout   : 120s (2m)        Hard power cut if OS hangs

On a CQ40N the same command lists that platform’s five timers instead, and adds a Delay Unit line showing whether they are currently being counted in minutes or seconds.

Read one timer. The get keyword is optional, so pcu-cli ign sw-off-delay reads the same value:

$ pcu-cli ign get sw-off-delay
  Shutdown Delay: 300s (5m)

Writing a timer asks for confirmation, then reads the value back and reports it as verified:

$ pcu-cli ign set sw-off-delay 120
Write Shutdown Delay = 120s (2m)? [y/N] y
  Shutdown Delay: 120s (2m) - verified

A value outside the timer’s range is rejected before anything is written, and the tool shows the default and recommended range (exit code 1):

$ pcu-cli ign set sw-off-delay 9000
ERROR: Shutdown Delay must be 3-7200s. Got: 9000
  Default: 300s (5m)  |  Recommended: 30-300s

On a platform without ignition timers (the CQ40 series), the command reports that the feature is unavailable and exits with code 2:

$ pcu-cli ign
ERROR: Ignition timers are not available on In-CarPC CQ40 series.

ign unit

The CQ40N series counts four of its five timers in a unit you can change between minutes and seconds. pcu-cli ign unit reads that setting, and pcu-cli ign unit minutes or pcu-cli ign unit seconds changes it. The value words are flexible: m, min, mins, minute, and minutes are all accepted, as are s, sec, secs, second, and seconds.

Reading it prints one indented line, Delay unit: minutes or Delay unit: seconds. With --quiet you get the bare word on its own line, which is the form to parse in a script.

Changing the unit does not convert the stored timer values

The MCU stores those four timers as plain counts. Switching the unit changes what the counts mean and nothing recalculates them, so a Force Off Timeout of 15 becomes fifteen seconds instead of fifteen minutes. ign unit warns about this and asks you to confirm before writing, then reminds you to re-check the timers with pcu-cli ign. Always do so. See The delay unit.

The confirmation prompt spells out the consequence before asking, and the prompt is printed to stderr like every other pcu confirmation. After a successful change pcu reads the setting back and reports it as verified, then prints a reminder that the timer values were not converted.

On a platform with no such setting (the CQ20 and the CQ40 series), the command reports that and exits with code 2:

ERROR: This platform has no delay unit setting. Its timers are always counted in seconds.

dio

Monitor digital inputs and the ignition line, and switch digital outputs. Available on the CQ40 series only.

Older models: use CQUtils for now

pcu is new, and we are still backporting support for older In-CarPC models, including digital I/O. More models will be supported soon. If your machine is not yet supported, use the CQUtils program preinstalled on the desktop in the meantime. Not sure which applies to your machine? Contact In-CarPC support.

Channel	Direction	Description
di1, di2	Input (read-only)	Digital inputs.
do1, do2	Output (read/write)	Digital outputs.
ign	Input (read-only)	Ignition / accessory sense line.

Command	Description
pcu-cli dio	Show all digital inputs, outputs, and the ignition line.
pcu-cli dio get <channel>	Read one channel. Shorthand: pcu-cli dio di1.
`pcu-cli dio set <do#> <0	1>`

$ pcu-cli dio
pcu v1.1.0  - In-CarPC CQ40 series Digital I/O
----------------------------------------
  DI1                 : Low
  DI2                 : Low
  DO1                 : Low
  DO2                 : Low
  Ignition (IGN)      : On

  Note: outputs reset to off on reboot or power loss; the state is not saved.

Read one channel. The channel keyword is optional, so pcu-cli dio di1 reads the same value:

$ pcu-cli dio get di1
  DI1: Low

Setting an output warns that outputs drive real hardware, asks to confirm, then reads the state back:

$ pcu-cli dio set do1 1
WARNING: digital outputs drive connected hardware (relays / switches / lamps).
Set DO1 = High? [y/N] y
  DO1: High - verified

Note

Output state is not saved across a restart. On reboot or power loss the outputs return to off. To assert an output at startup, run pcu-cli dio set from a boot script. See Digital I/O.

On a platform without digital I/O (the CQ20, and the CQ40N series, where digital I/O is a later phase), the command reports that the feature is unavailable and exits with code 2:

$ pcu-cli dio
ERROR: Digital I/O is not available on In-CarPC CQ20.

driver

Manage the PawnIO kernel driver. Windows only. See Install on Windows for the full driver setup.

Command	Description
pcu-cli driver [status|install|uninstall]	Check, install, or remove the PawnIO driver.

With no sub-command, pcu-cli driver shows status:

$ pcu-cli driver status
  PawnIO driver: v2.2.0 (2026-03-15)
  SmbusI801 module: 2025-05-05
  Status: Installed

On Linux there is no PawnIO driver; the kernel i2c-dev module is used instead, so the command exits with code 2:

$ pcu-cli driver status
PawnIO is a Windows-only driver. Linux uses the kernel i2c-dev module.

The --json and --quiet flags have no effect on driver; its output is always the text form shown above.

version and help

Command	Description
pcu-cli version	Show version, driver, and supported platforms.
pcu-cli --version, pcu-cli -V	Same as version. Runs without elevation.
pcu-cli help	Show command help, timer ranges, flags, and exit codes.

version prints the tool version and build stamp, the driver and module versions (Windows), and the supported-platform list with validated configurations. Add --json for a machine-readable form; see Scripting and Automation. help prints the command reference, including each timer’s range, default, and recommended range. On recognised hardware it covers just that platform; on an unrecognised machine it lists every platform’s timers under a model heading. See Help and the menu match your machine. Timers whose unit is selectable are listed without a unit, because a printed reference cannot know what ign unit is currently set to.

Confirmation prompts

Commands that change hardware ask before writing:

• pcu-cli ign set <timer> <value> prompts Write <timer> = <value>? [y/N].
• pcu-cli ign unit <minutes|seconds> explains that the stored values are not converted, then prompts Set the delay unit to <unit>? [y/N].
• pcu-cli dio set <do#> <0|1> warns about connected hardware, then prompts Set <channel> = <High|Low>? [y/N].
• pcu-cli driver install / uninstall prompt before running the installer.

Answering anything other than y aborts with exit code 1. Prompts are printed to stderr, so they never mix into piped output. For ign set, ign unit, and dio set, a prompt is skipped when you pass --yes (or -y), when you pass --quiet, or when input is redirected from a pipe or file. For driver install / uninstall, only --yes (or -y) or redirected input skips the prompt; --quiet has no effect on driver. See the redirected-input caution on the scripting page before automating writes.

Exit codes

Code	Meaning
0	Success.
1	Error, including a rejected value, an aborted confirmation, or a write that did not read back as expected.
2	Feature not available on this platform or build.