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+# Introduction
+
+This file describes configuration settings for Segatools that are common to
+all games.
+
+Keyboard binding settings use [Virtual-Key Codes](https://docs.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes).
+
+# `[aime]`
+
+Controls emulation of the Aime card reader assembly.
+
+## `enable`
+
+Default: `1`
+
+Enable Aime card reader assembly emulation. Disable to use a real SEGA Aime
+reader (COM port number varies by game).
+
+## `aimePath`
+
+Default: `DEVICE\aime.txt`
+
+Path to a text file containing a classic Aime IC card ID. **This does not
+currently work**.
+
+## `felicaPath`
+
+Default: `DEVICE\felica.txt`
+
+Path to a text file containing a FeliCa e-cash card IDm serial number.
+
+## `felicaGen`
+
+Default: `1`
+
+Whether to generate a random FeliCa ID if the file at `felicaPath` does not
+exist.
+
+## `scan`
+
+Default: `0x0D` (`VK_RETURN`)
+
+Virtual-key code. If this button is **held** then the emulated IC card reader
+emulates an IC card in its proximity. A variety of different IC cards can be
+emulated; the exact choice of card that is emulated depends on the presence or
+absence of the configured card ID files.
+
+# `[amvideo]`
+
+Controls the `amvideo.dll` stub built into Segatools. This is a DLL that is
+normally present on the SEGA operating system image which is responsible for
+changing screen resolution and orientation.
+
+## `enable`
+
+Default: `1`
+
+Enable stub `amvideo.dll`. Disable to use a real `amvideo.dll` build. Note that
+you must have the correct registry settings installed and you must use the
+version of `amvideo.dll` that matches your GPU vendor (since these DLLs make
+use of vendor-specific APIs).
+
+# `[clock]`
+
+Controls hooks for Windows time-of-day APIs.
+
+## `timezone`
+
+Default: `1`
+
+Make the system time zone appear to be JST. SEGA games malfunction in strange
+ways if the system time zone is not JST. There should not be any reason to
+disable this hook other than possible implementation bugs, but the option is
+provided if you need it.
+
+## `timewarp`
+
+Default: `0`
+
+Experimental time-of-day warping hook that skips over the hardcoded server
+maintenance period. Causes an incorrect in-game time-of-day to be reported.
+Better solutions for this problem exist and this feature will probably be
+removed soon.
+
+## `writeable`
+
+Default: `0`
+
+Allow game to adjust system clock and time zone settings. This should normally
+be left at `0`, but the option is provided if you need it.
+
+# `[dns]`
+
+Controls redirection of network server hostname lookups
+
+## `default`
+
+Default: `localhost`
+
+Controls hostname of all of the common network services servers, unless
+overriden by a specific setting below. Most users will only need to change this
+setting. Also, loopback addresses are specifically checked for and rejected by
+the games themselves; this needs to be a LAN or WAN IP (or a hostname that
+resolves to one).
+
+## `router`
+
+Default: Empty string (i.e. use value from `default` setting)
+
+Overrides the target of the `tenporouter.loc` and `bbrouter.loc` hostname
+lookups.
+
+## `startup`
+
+Default: Empty string (i.e. use value from `default` setting)
+
+Overrides the target of the `naominet.jp` host lookup.
+
+## `billing`
+
+Default: Empty string (i.e. use value from `default` setting)
+
+Overrides the target of the `ib.naominet.jp` host lookup.
+
+## `aimedb`
+
+Default: Empty string (i.e. use value from `default` setting)
+
+Overrides the target of the `aime.naominet.jp` host lookup.
+
+# `[ds]`
+
+Controls emulation of the "DS (Dallas Semiconductor) EEPROM" chip on the AMEX
+PCIe board. This is a small (32 byte) EEPROM that contains serial number and
+region code information. It is not normally written to outside of inital
+factory provisioning of a Sega Nu.
+
+## `enable`
+
+Default: `1`
+
+Enable DS EEPROM emulation. Disable to use the DS EEPROM chip on a real AMEX.
+
+## `region`
+
+Default: `1`
+
+AMEX Board region code. This appears to be a bit mask?
+
+- `1`: Japan
+- `2`: USA? (Dead code, not used)
+- `4`: Export
+- `8`: China
+
+## `serialNo`
+
+Default `AAVE-01A99999999`
+
+"MAIN ID" serial number. First three characters are hardware series:
+
+- `AAV`: Nu-series
+- `AAW`: NuSX-series
+- `ACA`: ALLS-series
+
+# `[eeprom]`
+
+Controls emulation of the bulk EEPROM on the AMEX PCIe board. This chip stores
+status and configuration information.
+
+## `enable`
+
+Default: `1`
+
+Enable bulk EEPROM emulation. Disable to use the bulk EEPROM chip on a real
+AMEX.
+
+## `path`
+
+Default: `DEVICE\eeprom.bin`
+
+Path to the storage file for EEPROM emulation. This file is automatically
+created and initialized with a suitable number of zero bytes if it does not
+already exist.
+
+# `[gpio]`
+
+Configure emulation of the AMEX PCIe GPIO (General Purpose Input Output)
+controller.
+
+## `enable`
+
+Default: `1`
+
+Enable GPIO emulation. Disable to use the GPIO controller on a real AMEX.
+
+## `sw1`
+
+Default `0x70` (`VK_F1`)
+
+Keyboard binding for Nu chassis SW1 button (alternative Test)
+
+## `sw2`
+
+Default `0x71` (`VK_F2`)
+
+Keyboard binding for Nu chassis SW2 button (alternative Service)
+
+## `dipsw1` .. `dipsw8`
+
+Defaults: `1`, `0`, `0`, `0`, `0`, `0`, `0`, `0`
+
+Nu chassis DIP switch settings:
+
+- Switch 1: Game-specific, but usually controls the "distribution server"
+    setting. Exactly one arcade machine on a cabinet router must be set to the
+    Server setting.
+    - `0`: Client
+    - `1`: Server
+- Switch 2,3: Game-specific.
+    - Used by Mario&Sonic to configure cabinet ID, possibly other games.
+- Switch 4: Screen orientation. Only used by the Nu system startup program.
+    - `0`: YOKO/Horizontal
+    - `1`: TATE/Vertical
+- Switch 5,6,7: Screen resolution. Only used by the Nu system startup program.
+    - `000`: No change
+    - `100`: 640x480
+    - `010`: 1024x600
+    - `110`: 1024x768
+    - `001`: 1280x720
+    - `101`: 1280x1024
+    - `110`: 1360x768
+    - `111`: 1920x1080
+- Switch 8: Game-specific. Not used in any shipping game.
+
+# `[hwmon]`
+
+Configure stub implementation of the platform hardware monitor driver. The
+real implementation of this driver monitors CPU temperatures by reading from
+Intel Model Specific Registers, which is an action that is only permitted from
+kernel mode.
+
+## `enable`
+
+Default `1`
+
+Enable hwmon emulation. Disable to use the real hwmon driver.
+
+# `[jvs]`
+
+Configure emulation of the AMEX PCIe JVS *controller* (not IO board!)
+
+## `enable`
+
+Default `1`
+
+Enable JVS port emulation. Disable to use the JVS port on a real AMEX.
+
+# `[keychip]`
+
+Configure keychip emulation.
+
+## `enable`
+
+Enable keychip emulation. Disable to use a real keychip.
+
+## `id`
+
+Default: `A69E-01A88888888`
+
+Keychip serial number. Keychip serials observed in the wild follow this
+pattern: `A6xE-01Ayyyyyyyy`.
+
+## `gameId`
+
+Default: (Varies depending on game)
+
+Override the game's four-character model code. Changing this from the game's
+expected value will probably just cause a system error.
+
+## `platformId`
+
+Default: (Varies depending on game)
+
+Override the game's four-character platform code (e.g. `AAV2` for Nu 2). This
+is actually supposed to be a separate three-character `platformId` and
+integer `modelType` setting, but they are combined here for convenience. Valid
+values include:
+
+- `AAV0`: Nu 1 (Project DIVA)
+- `AAV1`: Nu 1.1 (Chunithm)
+- `AAV2`: Nu 2 (Initial D Zero)
+- `AAW0`: NuSX 1
+- `AAW1`: NuSX 1.1
+- `ACA0`: ALLS UX
+- `ACA1`: ALLS HX
+- `ACA2`: ALLS HX2
+
+## `region`
+
+Default: `1`
+
+Override the keychip's region code. Most games seem to pay attention to the
+DS EEPROM region code and not the keychip region code, and this seems to be
+a bit mask that controls which Nu PCB region codes this keychip is authorized
+for. So it probably only affects the system software and not the game software.
+Bit values are:
+
+- 1: JPN: Japan
+- 2: USA (unused)
+- 3: EXP: Export (for Asian markets)
+- 4: CHS: China (Simplified Chinese?)
+
+## `systemFlag`
+
+Default: `0x64`
+
+An 8-bit bitfield of unclear meaning. The least significant bit indicates a
+developer dongle, I think? Changing this doesn't seem to have any effect on
+anything other than Project DIVA.
+
+Other values observed in the wild:
+
+- `0x04`: SDCH, SDCA
+- `0x20`: SDCA
+
+## `subnet`
+
+Default `192.168.100.0`
+
+The LAN IP range that the game will expect. The prefix length is hardcoded into
+the game program: for some games this is `/24`, for others it is `/20`.
+
+# `[netenv]`
+
+Configure network environment virtualization. This module helps bypass various
+restrictions placed upon the game's LAN environment.
+
+## `enable`
+
+Default `1`
+
+Enable network environment virtualization. You may need to disable this if
+you want to do any head-to-head play on your LAN.
+
+Note: The virtualized LAN IP range is taken from the emulated keychip's
+`subnet` setting.
+
+## `addrSuffix`
+
+Default: `11`
+
+The final octet of the local host's IP address on the virtualized subnet (so,
+if the keychip subnet is `192.168.32.0` and this value is set to `11`, then the
+local host's virtualized LAN IP is `192.168.32.11`).
+
+## `routerSuffix`
+
+Default: `1`
+
+The final octet of the default gateway's IP address on the virtualized subnet.
+
+## `macAddr`
+
+Default: `01:02:03:04:05:06`
+
+The MAC address of the virtualized Ethernet adapter. The exact value shouldn't
+ever matter.
+
+# `[pcbid]`
+
+Configure Windows host name virtualization. The ALLS-series platform no longer
+has an AMEX board, so the MAIN ID serial number is stored in the Windows
+hostname.
+
+## `enable`
+
+Default: `1`
+
+Enable Windows host name virtualization. This is only needed for ALLS-platform
+games (since the ALLS lacks an AMEX and therefore has no DS EEPROM, so it needs
+another way to store the PCB serial), but it does no harm on games that run on
+earlier hardware.
+
+## `serialNo`
+
+Default: `ACAE01A99999999`
+
+Set the Windows host name. This should be an ALLS MAIN ID, without the
+hyphen (which is not a valid character in a Windows host name).
+
+# `[sram]`
+
+Configure emulation of the AMEX PCIe battery-backed SRAM. This stores
+bookkeeping state and settings. This file is automatically created and
+initialized with a suitable number of zero bytes if it does not already exist.
+
+## `enable`
+
+Default `1`
+
+Enable SRAM emulation. Disable to use the SRAM on a real AMEX.
+
+## `path`
+
+Default `DEVICE\sram.bin`
+
+Path to the storage file for SRAM emulation.
+
+# `[vfs]`
+
+Configure Windows path redirection hooks.
+
+## `enable`
+
+Default: `1`
+
+Enable path redirection.
+
+## `amfs`
+
+Default: Empty string (causes a startup error)
+
+Configure the location of the SEGA AMFS volume. Stored on the `E` partition on
+real hardware.
+
+## `appdata`
+
+Default: Empty string (causes a startup error)
+
+Configure the location of the SEGA "APPDATA" volume (nothing to do with the
+Windows user's `%APPDATA%` directory). Stored on the `Y` partition on real
+hardware.
+
+## `option`
+
+Default: Empty string
+
+Configure the location of the "Option" data mount point. This mount point is
+optional (hence the name, probably) and contains directories which contain
+minor over-the-air content updates.