UM10208_2
© NXP B.V. 2007. All rights reserved.
User manual
Rev. 02 — 1 June 2007
309 of 362
NXP Semiconductors
UM10208
Chapter 24: LPC2800 LCD
4.9 Data Byte Register (LCDDBYTE - 0x8010 3030)
4.10 Instruction Word Register (LCDIWORD - 0x8010 3040)
4.11 Data Word Register (LCDDWORD - 0x8010 3080)
5.
LCD interface operation
5.1 Resetting a Remote Device
Either:
1. connect a GPIO pin to the Reset pin of the device, and program the GPIO to drive the
signal to its active state, then its inactive state, OR
2. if the device has a Reset command, write it to LCDIBYTE.
5.2 Programming the LCD interface clock
As noted in
, the Clock Generation Unit (CGU) generates two
clocks for the LCD interface, called “PCLK” and “LCD clock”. PCLK is used for reading
and writing registers in the LCD interface, while the LCD clock is used to operate the LCD
interface. PCLK is typically identical to the processor clock, while the LCD clock must be
generated in “stretched mode” by one of the CGU’s available fractional dividers to meet all
of the following constraints:
Table 359. Data Byte Register (LCDDBYTE - 0x8010 3030)
Bit
Symbol
Description
Reset
value
7:0
Writing to this register places this byte in the output FIFO, tagged as a
data byte. After reading has been initiated, and bit 4 of the LCDSTAT
register has gone from 1 to 0, the byte from the remote device can be
read from this register (or equivalently LCDIBYTE).
0
31:8
-
Reserved, user software should not write ones to reserved bits. The
value read from a reserved bit is not defined.
-
Table 360. Instruction Word Register (LCDIWORD - 0x8010 3040) Write Only
Bit
Symbol
Description
Reset
value
31:0
Writing to this register places four bytes in the output FIFO, tagged as
instruction bytes. The byte in bits 7:0 is sent first, the byte in bits 31:24
is sent last.
0
Table 361. Data Word Register (LCDDWORD - 0x8010 3080) Write Only
Bit
Symbol
Description
Reset
value
7:0
Writing to this register places this byte in the output FIFO, tagged as an
instruction byte. After reading has been initiated, and bit 4 of the
LCDSTAT register has gone from 1 to 0, the byte from the remote
device can be read from this register (or equivalently LCDDBYTE).
0
31:8
-
Reserved, user software should not write ones to reserved bits. The
value read from a reserved bit is not defined.
-