sed1355 ETC-unknow, sed1355 Datasheet - Page 427

• Manufacturer Part Number: sed1355
• Description: Sed1355 Embedded Ramdac Lcd/crt Controller
• Manufacturer: ETC-unknow

Epson Research and Development
Vancouver Design Center
3.2 Host Bus Interface Signals Descriptions
Interfacing to the NEC VR4102/VR4111™ Microprocessors
Issue Date: 99/05/05
The SED1355 MIPS/ISA Host Bus Interface requires the following signals.
• BUSCLK is a clock input which is required by the SED1355 Host Bus Interface. It is
• The address inputs AB[20:0], and the data bus DB[15:0], connect directly to the
• M/R# (memory/register) selects between memory or register access. It may be
• Chip Select (CS#) must be driven low by LCDCS# whenever the SED1355 is accessed
• WE1# connects to SHB# (the high byte enable signal from the VR4102/VR4111) which
• WE0# connects to WR# (the write enable signal from the VR4102/VR4111) and must
• RD# connects to RD# (the read enable signal from the VR4102/VR4111) and must be
• WAIT# connects to LCDRDY and is a signal output from the SED1355 that indicates
• The BS# and RD/WR# signals are not used for the MIPS/ISA Host Bus Interface and
separate from the input clock (CLKI) and is typically driven by the host CPU system
clock.
VR4102/VR4111 address (ADD[20:0]) and data bus (DAT[15:0]), respectively. MD4
must be set to select the proper endian mode upon reset.
connected to an address line, allowing system address ADD21 to be connected to the
M/R# line.
by the VR4102/VR4111.
in conjunction with address bit 0 allows byte steering of read and write operations.
be driven low when the VR4102/VR4111 is writing data to the SED1355.
driven low when the VR4102/VR4111 is reading data from the SED1355.
the VR4102/VR4111 must wait until data is ready (read cycle) or accepted (write cycle)
on the host bus. Since VR4102/VR4111 accesses to the SED1355 may occur asynchro-
nously to the display update, it is possible that contention may occur in accessing the
SED1355 internal registers and/or display buffer. The WAIT# line resolves these
contentions by forcing the host to wait until the resource arbitration is complete.
should be tied high (connected to V
DD
).
X23A-G-007-05
SED1355
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