*FX10	Set flash rate of second colour in fiftieths of a second (default
	setting 25).
	*FX10,0 disables flashing and forces the second colour on the
	screen;
	*FX10,5 sets the flash rate to one tenth of a second.
*FX11	Set keyboard auto-repeat delay in hundredths of a second
	(default setting 32 or as set by *CONFIGURE DELAY).
	*FX11,0 disables auto-repeat;
	*FX11,10 sets auto-repeat delay to one tenth of a second.
*FX12	Set keyboard auto-repeat period in hundredths of a second
	(default setting 8 or as set by *CONFIGURE REPEAT).
	*FX12,0 restores default settings of auto-repeat delay and
	auto-repeat period;
	*FX12,3 sets auto-repeat period to three hundredths of a
	second.
*FX13	Disable various events.
*FX14	Enable various events.
*FX15	Flush buffers:
	*FX15,0 flushes all buffers;
	*FX15,1 flushes current input buffer.
*FX18	Clear user-defined function key definitions.
*FX19	Wait for vertical synchronisation.
*FX20	Restore default font definitions te. reset the characters
	corresponding to ASCII codes 32 to 126 to normal.
*FX21	Flush selected buffer:
	*FX21,0 keyboard buffer;
	*FX21,1 RS232 (optional) input buffer;
	*FX21,2 RS232 (optional) output buffer;
	*FX21,3 printer buffer;
	*FX21,4 sound channel 0;
	*FX21,5 sound channel I;
	*FX21,6 sound channel 2;
	*FX2 ,7 sound channel 3.
*FX22	Increment ROM polling semaphore.
*FX23	Decrement ROM Polling sernaphore.
App 4.3