SED1354 Datasheet, PDF (361/472 Pages) Epson Company – Color Graphics LCD/CRT Controller

Epson Research and Development
Vancouver Design Center
Page 9
2.1.2 LCD Memory Access Cycles
Once an address in the LCD block of memory is placed on the external address bus
(ADD[25:0]), the LCD chip select (LCDCS#) is driven low. The read or write enable
signals (RD# or WR#) are driven low for the appropriate cycle and LCDRDY is driven low
to insert wait states into the cycle. The high byte enable (SHB#) is driven low for 16-bit
transfers and high for 8-bit transfers.
The following figure illustrates typical NEC VR4102 memory read and write cycles to the
LCD controller interface.
TCLK
ADD[25:0]
SHB#
LCDCS#
WR#,RD#
VALID
D[15:0]
(write)
D[15:0]
(read)
LCDRDY
VALID
Hi-Z
VALID
Hi-Z
Figure 2-1: NEC VR4102 Read/Write Cycles
Interfacing to the NEC VR4102™ Microprocessor
Issue Date: 99/03/10
SED1354
X19A-G-007-06