code	abbreviation	meaning
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0x0A		E	command end
'a'		A	command succesful executed
'n'		N	command unknown or execution error
'c'		C	continue, send next byte
0..9,A..F	H	hex number (only upper case)
0x00..0xFF	B	byte


PC			programmer
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"Magic",E		A		enable in system programmer
"Reset",E		A		disable in system programmer,
					reset target

"Vers",E;C;C;C;C;C;E	H;H;H;H;H;H:A	version code (6 hex nunbers)
"D1200",E		A		set target type (1200)
"DE1200",E		A		select EEPROM of target
"U12V",E		A		set program voltage
"Size",H,H,H,H,E	A		set target size (4 hex numbers)
"Check",E;C;C;C;C;C;E	H;H;H;H;H;H;A	checksum (6 hex numbers)
"Rsig",E;C;C;C;C;C;E	H;H;H;H;H;H;A	Read Signature
"Erase",E		A		erase target

"Read",H,H,H,H,E	B		set address HHHH, read 1 byte
C			B		read next byte
E			A		end read

"Prog",H,H,H,H,E,B	A		program 1 byte
			or
			N		program failed (e.g. if not erased)
B			A		program next byte
0xA5,0xA5		A		program byte 0xA5
0xa5,0x00		A		end program
	
"Lock?",E;E		H;A		read lock mode (0..3)
			or
			N		read lock mode not supported
"Lock",H,E		A		set lock mode (0..3)

"Fuse?",E;C;E		H;H;A		read fuse (max 8 bits)
			or
			N		read fuse not supported
"Fuse",H,H,E		A		set fuse bits
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