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README.md

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-# SIO2BT OS Patcher
-
-With this tool you can patch the original ATARI 8-bit OS ROMs
-to make them compatible with SIO communication over Bluetooth 
+# SIO2BT OS Patcher
+
+With this tool you can patch the original ATARI 8-bit OS ROMs
+to make them compatible with SIO communication over Bluetooth 
+
+SIO2BT_OS_Patcher detects most common versions of the ATARI OS and let you patch them according to your needs.
+Depending on the OS, only some of the parameters will be adjustable (the rest is grayed out in such case):
+
+Timeout
+-------
+The SIO timeout is the only "MUST HAVE" change if you want to use your patched OS with SIO2BT.
+Default OS value (16ms for NTSC / 20ms for PAL) is too small for communication over Bluetooth.
+The average answer time over Bluetooth is ~40ms, so you should be fine with 100ms, 
+but I recommend to select the largest timeout (240ms for NTSC / 300ms for PAL) to be on the safe side.
+
+Retry count
+-----------
+Retry count can be decreased to minimize waiting time, when ATARI starts without a disk drive.
+You can compensate bigger timeouts with a smaller number of re-tries.
+Default OS value is 13 and the recommended value for SIO2BT is 5.
+
+Disable poll for new devices
+----------------------------
+ATARI XL/XE tries (at start-up) to detect "new devices" with so called "3F" poll.
+This procedure is explained in the XL Addendum to the Operating System Manual.
+However no such device exists and the "3F" poll delays startup when ATARI is powered on without a disk drive.
+I recommend to disable the poll.
+
+Enable Coldstart with Shift+Reset
+---------------------------------
+It is a convenience feature to force a coldstart when the shift+reset button combination is pressed.
+When SIO2BT is powered from the ATARI, you can use it to load new games without a need to re-establish Bluetooth connection every time.
+
+Select Atarimax Bank 0 at Coldstart
+-----------------------------------
+Optionally the shift+reset button combination may also reset Atarimax multicart cartridges.
+Writing at $D500 activates bank 0, where a cart menu is located.
+As a result pressing shift+reset would not only trigger the ATARI coldstart, but also reset the Atarimax cart.
+This option is available only together with the previous one and it has no relation to SIO2BT.
+
+Default Basic Off
+-----------------
+You may invert the logic and make BASIC disabled per default.
+In that case you have to keep OPTION key pressed at start-up to activate BASIC.
+
+Enable HiSpeed
+--------------
+You can patch XL and XE OS ROMs with a modified HighSpeed patch from HIAS (https://www.horus.com/~hias/atari/#hipatch).
+The original HIAS's patch applies only to Disk Drives and does not support SIO2BT.
+I created a fork of the source code repository (https://github.com/TheMontezuma/highspeed-sio) and added support for all SIO devices (SIO2BT emulates also SmartDevice and NetworkingDevice) and adapted baudrate detection to support SIO2BT.