Keyboard: Make tada68 build .bin files by default (#3630)

keyboards/tada68/readme.md

@@ -9,10 +9,14 @@ Hardware Availability: [kbdfans](https://kbdfans.myshopify.com/products/tada68-m
 
 Make example for this keyboard (after setting up your build environment):
 
-    make tada68:default:bin
+    make tada68:default
 
 See [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) then the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information.
 
+## Firmware Format
+
+Out of the box the tada68 uses a .bin firmware file instead of a .hex like other custom keyboards. By default QMK will build and copy the correct .bin file for you. If for some reason you need a hex file instead, you can add `:hex` to your make command, or look inside `qmk_firmware/.build` to find the hex file.
+
 ## Flashing Instructions (Win)
 
 *Read all the instructions, there are a few warnings of things to avoid doing to avoid bricking your Tada68. __It is much too easy to do!__*

keyboards/tada68/rules.mk

@@ -48,6 +48,8 @@ OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
 #   USBaspLoader     2048
 OPT_DEFS += -DBOOTLOADER_SIZE=4096
 
+# Mass storage bootloader on the tada68 uses bin files
+FIRMWARE_FORMAT=bin
 
 # Build Options
 #   comment out to disable the options.