add start of batch programming info

docs/firmware-install.md

@@ -0,0 +1,81 @@
+
+# Installing firmware on TouchwheelSAO board
+
+Use any Windows, MacOS, Linux, RaspberryPi host with USB-to-serial adapter.
+
+## Hardware prep
+
+The TouchwheelSAO board has the UPDI programming port brought out as a 4-pin
+SMD header, which a 4-pin pin header can be soldered, or a 4-pin 0.1" spacing
+pogo-pin jig clamp can be attached.
+
+The pins on the TouchWheelSAO board are laid out for use with a
+[USB-to-serial adapter wired as a UPDI programmer](https://learn.adafruit.com/adafruit-attiny817-seesaw/advanced-reprogramming-with-updi)
+but you can also use a standard UPDI programmer too.
+
+Here is what a programmer setup could look like, using:
+* [cheap USB-to-serial dongle](https://amzn.to/47sMaxz)
+* [Pogo pin probe clip](https://www.digikey.com/short/3c99n5p9)
+
+<a href="./firmware-programming1.jpg"><img src="./firmware-programming1.jpg" width=400></a>
+
+
+## Software, Compiling, Uploading
+
+Instead of installing the Arduino GUI, we can use [arduino-cli](https://arduino.github.io/arduino-cli/1.0/)
+
+### Install arduino-cli
+
+```sh
+curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | sh
+```
+
+### Install megatinycore 
+
+```sh
+arduino-cli core install megatinycore:megaavr  --additional-urls https://drazzy.com/package_drazzy.com_index.json
+ ```
+
+### (optional) Show some details on the core:
+
+```sh
+arduino-cli board details -b megaTinyCore:megaavr:atxy6
+```
+
+
+### Compile:
+
+```sh
+arduino-cli compile --verbose -fqbn megaTinyCore:megaavr:atxy6:chip=816,printf=minimal \
+            --build-path=$(pwd)/build TouchwheelSAO_attiny816
+```
+
+
+### Upload
+
+```sh
+arduino-cli upload --verbose --fqbn megaTinyCore:megaavr:atxy6:chip=816  \
+            --port /dev/ttyUSB0 --programmer serialupdi57k  \
+            --input-dir ./build
+
+```
+
+### Shell script for batch programming
+
+Also see firmware/batch-program.sh
+
+```sh
+#!/bin/bash
+
+PORT=/dev/ttyUSB0
+HEX_FILE=./build/TouchwheelSAO_attiny816.ino.hex
+
+while [ 1 ] ; do
+  read -rsn1 -p"Press any key program firmware"; echo
+  arduino-cli upload --verbose --fqbn megaTinyCore:megaavr:atxy6:chip=816  \
+              --port $PORT --programmer serialupdi57k  \
+              --input-file=$HEX_FILE
+  echo "--------------------"
+done
+
+```

firmware/batch-program.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+# Batch firmware programming of TouchWheelSAO using arduino-cli
+# Requires arduino-cli to be set up as described in "firmware-install.md"
+
+PORT=/dev/ttyUSB0
+HEX_FILE=./build/TouchwheelSAO_attiny816.ino.hex
+
+while [ 1 ] ; do
+  read -rsn1 -p"Press any key program firmware"; echo
+  arduino-cli upload --verbose --fqbn megaTinyCore:megaavr:atxy6:chip=816  \
+              --port $PORT --programmer serialupdi57k  \
+              --input-file=$HEX_FILE
+  echo "--------------------"
+done
+
+
+
+

schematics/TouchwheelSAO/TouchwheelSAO.kicad_pro

@@ -58,7 +58,11 @@
           "width": 0.0
         }
       ],
-      "drc_exclusions": [],
+      "drc_exclusions": [
+        "lib_footprint_mismatch|182027500|100000000|db117cee-737c-4e38-9bae-adc6dc6d8dea|00000000-0000-0000-0000-000000000000",
+        "solder_mask_bridge|207882362|77471632|804fe2a1-0b51-4403-99d2-90168c6589a2|e4960331-6806-4396-8c2b-5fd922360b5c",
+        "text_thickness|209200000|77200000|6004d729-f48b-46a7-9010-33c0f774deac|00000000-0000-0000-0000-000000000000"
+      ],
       "meta": {
         "version": 2
       },