Update Readme.

README.md

@@ -7,12 +7,15 @@ Port of MiST version by Szombathelyi Gyorgy
 - Selectable ZX80/ZX81
 - 16k/32k/48k RAM packs
 - 8KB with CHR$128/UDG addon
+- QS CHRS (press F1 to enable/disable the alternative chars)
+- CHROMA81
 - Turbo in Slow mode: NoWait, x2, x8
 - YM2149 sound chip (ZON X-81 compatible)
-- Joystick types: Cursor, Sinclar, ZX81
+- Joystick types: Cursor, Sinclar, ZX81, ZXpand
 - PAL/NTSC timings
 - Turbo loading of .o and .p files
 - Load alternative ROM.
+- Load colorization and char files
 
 ### Install
 copy *.rbf to the root of SD card.
@@ -21,3 +24,26 @@ copy *.rbf to the root of SD card.
 Selecting an .o (ZX80) or .p (ZX81) file opens the tape. This is indicated by the
 user LED. The LOAD command will load it as it would be on a standard tape.
 Reset (ALT-F11 or the Reset OSD option) closes the .o or .p file.
+
+### Joystick
+OSD menu allows to switch joysticks between Cursor, Sinclar, ZX81. ZXpand joystick is always enabled.
+Other kinds of joystick will be disabled if ZXpand access is detected to avoid collisions.
+Only direct ZXpand joystick port is supported. $1FFE call is not supported as the ZXpand ROM is not used.
+
+### Colorization and Char files
+Core supports .col and .chr files loading together with main .p file if the have the same name.
+For proper .col file work, CHROMA81 should be enabled before loading. For .chr file QS CHRS should be enabled before loading.
+
+Check [this site](http://www.fruitcake.plus.com/Sinclair/ZX81/Chroma/ChromaInterface_Software.htm) for games adapted for colors.
+
+**MiSTer binary should be updated to 20180903 or later to support .col/.chr files.**
+
+### Options
+ZX81 has many options and for most games, it's better to set:
+* Main RAM: 16KB
+* Low RAM: 8KB
+* CHR$128: 128 chars
+* QD CHRS: enabled
+* CHROMA81: enabled
+
+Some games may require specific settings - check the proper sites.