documentation updates...

- fleshed out main README.md a bit
- improved github formatting for docs/which-hex-file.md
- added 'make docs' to preview .md files as .html
- ignore html files generated by 'make docs'
- removed rampingios-v3.html file generated years ago

1 files changed, 86 insertions, 3 deletions

diff --git a/README.md b/README.md
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 # Anduril Flashlight Firmware + FSM Flashlight UI Toolkit
 
-Anduril is a user interface for flashlights, written on top of FSM (F-word
-Spaghetti Monster), a UI toolkit for flashlights.
+Anduril is a user interface for flashlights.  It is written with FSM, a UI
+toolkit for flashlights.
 
-## Flashing
+What is FSM?  The "SM" means "Spaghetti Monster", and the "F" can be any F word
+you like, such as "Flashlight" or whatever suits your mood.  FSM also means
+"Finite State Machine", which is the type of abstraction used for defining user
+interfaces.  It is like a flowchart turned into executable code.
+
+## Using Anduril
+
+Anduril has many features, but the only things a person *really* needs to know
+to use it are:
+
+  - Click for on/off
+  - Hold to change brightness
+
+For more in-depth use, read its [user manual](docs/anduril-manual.txt)
+for full details.
+
+If you want to know what changed recently, check the [ChangeLog](ChangeLog.md).
+
+## Flashing Firmware
+
+Get the latest updates by flashing new firmware!
+
+A few things are needed to flash firmware:
+
+  - A firmware ".hex" file.  Here's
+    [how to find the right .hex file](docs/which-hex-file.md).
+
+  - A flashing adapter.  The type of adapter depends on which MCU chip your
+    light uses.  It may be an UPDI 3-pin adapter (attiny1616 and newer) or an
+    AVR ISP 6-pin adapter (attiny85, attiny1634).
+
+    **UPDI** typically uses a "pogo pin" adapter, with spring-loaded pins to
+    hold against copper pads on the driver circuit.
+
+    **AVR ISP** typically has two parts -- a USB device (like a USBASP), and a
+    physical adapter (like a pogo pin adapter or SOIC8 clip).  SOIC8 is the
+    least convenient, and is mostly only used on old models with attiny85
+    chips.
+
+  - A firmware flashing program.  A few compatible programs include
+    `avrdude`, `pymcuprog`, and `ZFlasher`.
+
+  - A computer or phone.  Almost any modern computer or phone should be able to
+    do it, as long as you can plug the adapter in and run a flashing program.
+
+One particularly useful guide is at https://anduril.click/ .
 
 ## Compiling
 
+The firmware can be deeply customized by modifying it and compiling your own
+versions, and this is encouraged.
+
+To compile the firmware, it is strongly recommended that you use a Linux
+computer, ideally running Debian or Ubuntu (but almost any distro should work).
+Virtual machines work well, such as running WSL inside Windows.  There is also
+a Docker container available (TODO: add link(s) here), if that is more
+convenient.
+
+### Prerequisites:
+
+  - AVR toolchain packages:  
+    `sudo apt install gcc-avr avr-libc binutils-avr avrdude`
+
+  - One or more Atmel DFPs (Device Family Pack) may be needed, to add support
+    for recent AVR MCUs.
+
+    - Download the Atmel ATtiny Series Device Support pack:
+      http://packs.download.atmel.com/
+
+    - Unzip the pack somewhere on your build computer
+
+    - Set ATTINY_DFP=/path/to/where/you/unzipped/the/pack
+      (either in your shell, or in this repo's bin/build.sh script)
+
+      `export ATTINY_DFP=$HOME/src/torches/atmel/attiny-dfp`
+
+### Building
+
+Use the `make` script included in this repo.  Run `./make --help` for details
+about how to use it.  In most cases though, you should be able to just run
+`./make` by itself to compile all available build targets.  Or give it a search
+term to limit builds to only a few, like `./make d4v2` to build all Emisar D4v2
+firmwares.
+
+The compiled firmware goes into the `hex/` directory, ready to be used by any
+firmware flashing program.
+