ARM ARM DUI 0224I manual Charcom, Chardat, Charrd, Charmask, Charstat

Programmer’s Reference

The control and data registers for the character LCD interface are listed in Table 4-25.

Table 4-25 Character LCD control and data registers

Address	Name	Type	Description
0x10008000	CHAR_COM	Write command, read	A write to this address will cause a write to the
		busy status	HD44780 command register some cycles later.A
			read from this address will cause a read from the
			HD44780 busy register some cycles later.
				Note
			The data read from this address is not valid LCD
			register data. Use the CHAR_RAW and
			CHAR_RD registers to return LCD register data.
0x10008004	CHAR_DAT	Write data RAM, read	A write to this address will cause a write to the
		data RAM	HD44780 data register some cycles later.A read
			to this address will cause a read to the HD44780
			data register some cycles later.The data read from
			this address is not valid LCD register data. Use
			the CHAR_RAW and CHAR_RD registers to
			return LCD register data.
0x10008008	CHAR_RD	Read captured data	Bits [7:0] contain the data from last request read,
		from an earlier read	valid only when bit 0 is set in CHAR_RAW. Bits
		command	[31:8] should be ignored.

0x1000800C CHAR_RAW	Write to reset access
	complete flag, read to
	determine if data in
	CHAR_RD is valid

Bit 0 indicates AccessComplete (write 0 to clear). The bit is set if read data is valid. Bits [31:1] should be ignored.

0x10008010	CHAR_MASK	Write interrupt mask	Set bit 0 to 1 to enable AccessComplete to
			generate an interrupt on SIC 7.
0x10008014	CHAR_STAT	Read status	Bit 0 is the state of AccessComplete ANDed with
			the CHAR_MASK

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