working on getting started guide

README.md

@@ -51,7 +51,7 @@ want one for review or testing? or more information about launch: [Link to Launc
 
 * Ultra low latency (0.5ms)
 
-* OLED display showing settings and status
+* OLED display
 
 * USB-C powered
 
@@ -97,7 +97,7 @@ But of course, one can argue that using period-correct peripherals is simply par
 
 ## Getting Started
 
-[Click me](kit_assembly.md)
+[Click me](getting_started.md)
 
 ## Technical Details
 
@@ -109,7 +109,15 @@ A kickstarter is planned, see [page] for details
 
 ### How is the latency?
 
-Additional latency from USB4VC is almost negligible. Depending on the Raspberry Pi generation, it can be from 0.5 to 1ms. [See details here]
+Depends on the Raspberry Pi you use:
+
+| RPi Generation | Latency |
+|----------------|---------|
+| 2              | 1ms     |
+| 3              | 0.63ms  |
+| 4              | 0.5ms   |
+
+1ms is *one thousandth* of a second. Hence, the delay from USB4VC is all but negligible.
 
 ### Which Raspberry Pi can I use?
 
@@ -122,6 +130,10 @@ Yes, but I can only work on so many at once, so in the beginning i will be focus
 
 If you're in UK and happy to let me your computer, let me know!
 
+### What does USB4VC stand for?
+
+USB for Vintage Computers, although there's nothing stopping it for vintage consoles too 🤔.
+
 ## Roadmap / Future Plans
 
 Launch with IBM PC and ADB because most popular, but look into more computers, and more protocols.
@@ -132,4 +144,3 @@ Olivetii M24
 SUN workstation
 Early macintoshes
 
-

getting_started.md

@@ -0,0 +1,77 @@
+# Getting Started with USB4VC
+
+[Get USB4VC](https://www.tindie.com/) | [Official Discord](https://discord.gg/4sJCBx5) | [Getting Started](getting_started.md) | Table of Contents
+
+------
+
+Congratulations on your new toy! Here is a short guide on how to use your USB4VC.
+
+## SD card Preparation
+
+If your USB4VC already comes with a SD card, feel free to [skip this step](#test-out-raspberry-pi)!
+
+Download image
+
+Burn through ethcher or rufus
+
+## Test out Raspberry Pi
+
+It's good practice to make sure your RPi works before mounting it into USB4VC.
+
+Insert SD card in Raspberry Pi, and hook it up to a monitor. No need for anything else.
+
+Power it on, and it should boot and end up with the program running, showing a bunch of information like this:
+
+[Photo Here]
+
+If so, congrats! Power off and continue.
+
+## Kit Assembly
+
+If your USB4VC has not been assembled yet, [see this guide](/kit_assembly_guide.md) to put it together.
+
+## Cable Connection
+
+**Keep your computer off for now!**
+
+Using the appropriate cable, connect the desired port from Protocol Card to your computer.
+
+Most of the peripherals are **NOT hot pluggable**, so make sure **all cables are connected before using!**
+
+Also plug in any USB Keyboard, Mouse, and Gamepad you're planning to use.
+
+If using Bluetooth, we can pair it later.
+
+## USB4VC Power On
+
+Power up USB4VC using a USB-C cable, you can do it from Protocol Card, Baseboard, or even RPi itself. All will work!
+
+[Top-down photo with arrows pointing to power ports]
+
+After a few seconds, the OLED screen should light up, showing some information:
+
+[photo of OLED showing home screen, with legends and arrows]
+
+Press `+` or `-` to switch pages, and `enter` button to enter the submenu. If you have a Bluetooth device, you can pair it in the menu.
+
+## Protocol Setup
+
+Looking at home screen, if displayed protocol is what you want, you're good to go!
+
+Otherwise, press `Enter` button, and you can switch protocols, adjust mouse sensitivity and gamepad linearity.
+
+I would suggest leaving the mouse sensitivity at 1 and adjust in the system if possible. Same with gamepads.
+
+## Try it out!
+
+With protocol set up, and cable connected, time to power on the computer!
+
+You should be able to use it as normal, now with USB inputs!
+
+## Advanced Features: Mapping gamepad to keyboard/mouse
+
+json file
+
+
+
+

launch_plan.md

@@ -19,3 +19,9 @@ Current launch timeline is:
 * Public Release
 
 * Work on Improvements, More Protocols and Protocol Cards
+
+
+## Help wanted!
+
+
+

technical_notes.md

@@ -0,0 +1,68 @@
+
+## How USB4VC Works
+
+USB4VC uses a Raspberry Pi running Linux, 
+
+input event codes
+
+parsed
+
+mapping
+
+## SPI Communication Protocol
+
+Raspberri Pi communicates with Protocol Card through SPI. [Here's a quick introduction](https://www.circuitbasics.com/basics-of-the-spi-communication-protocol/) if you're unfamiliar.
+
+RPi is master, P-card is slave. SPI mode 0 (CPOL and CPHA both 0), SCLK is 2MHz.
+
+include a sample capture.
+
+RPi and P-card talks via fixed-length 32-byte packets.
+
+Generally, first byte is magic number, second byte sequence number, thrid byte message type
+
+## Latency Information
+
+Input latency can be introduced during all stages of input chain. Using keyboards as example, we have:
+
+* Step 1: Switch physically depressed
+
+* Step 2: Keyboard sends out event on USB/Bluetooth
+
+* Step 3: Raspberry Pi processes the event and informs the Protocol Card
+
+* Step 4: Protocol Card sends out the keystroke to retro computer
+
+* Step 5: Retro computer responds to the keystroke.
+
+The part we're interested in is **Step 3 and 4**, as any time spent here is the additional delay from USB4VC.
+
+To accurately measure the delay, I used a logic analyzer connecting to keyboard USB lines and PS/2 output on the IBM PC Protocol Card. Here is the delay in action:
+
+![Alt text](photos/lag_zoom.png)
+
+From the keystroke appearing on USB, to keystroke appearing on PS/2, it took 487 *microseconds*.
+
+Zoomed out capture with multiple keypresses:
+
+![Alt text](photos/lag.png)
+
+I tested out different generations of Raspberry Pis, and here is the result:
+
+| RPi Generation | Avg. Latency |
+|----------------|---------|
+| 2              | 1ms     |
+| 3              | 0.63ms  |
+| 4              | 0.5ms   |
+
+You can find the [capture files here](captures/latency), open with [saleae app](https://www.saleae.com/downloads/), search `PID ACK` for USB input events, more info [in this video](https://www.youtube.com/watch?v=wdgULBpRoXk)
+
+
+## Developing your own Protocol Card
+
+SPI Format, AVR based arduino probably wont work, suggested to use STM32, include link.
+
+RPi Header pinout, explain what each pin does.
+
+Current limits etc.
+