Toshiba TLCS-900 Network Card User Manual


 
TMP92CZ26A
92CZ26A-220
3.10 SDRAM Controller (SDRAMC)
The TMP92CZ26A incorporates an SDRAM controller (SDRAMC) for accessing SDRAM that can
be used as data memory, program memory, or display memory.
The SDRAMC has the following features:
(1) Supported SDRAM
Data rate type : SDR (single data rate) type only
Memory capacity : 16 / 64 / 128 / 256 / 512 Mbits
Number of banks : 2 banks / 4 banks
Data bus width : 16 bits
Read burst length : 1 word / full page
Write mode : Single mode / Burst mode
(2) Supported initialization sequence commands
Precharge All command
Eight Auto Refresh commands
Mode Register Set command
(3) Access mode
CPU Cycle HDMA Cycle LCDC Cycle
Burst length 1 word 1 word or full page selectable Full page
Addressing mode Sequential Sequential Sequential
CAS latency (clock) 2 2 2
Write mode Single Single or burst selectable
(4) Access cycles
CPU access cycles
Read cycle : 1 word, 4-3-3-3 states (minimum)
Write cycle : Single, 3-2-2-2 states (minimum)
Data size : 1 byte / 1 word / 1 long-word
HDMA access cycles
Read cycle : 1 word, 4-3-3-3 states / full page, 4-1-1-1 states (minimum)
Write cycle : Single, 3-2-2-2 states (minimum) / burst, 2-1-1-1 states (minimum)
Data size : 1 byte / 1 word / 1 long-word
LCDC access cycles
Read cycle : Full page, 4-1-1-1 states (minimum)
Data size : 1 word
(5) Auto generation of refresh cycles
Auto Refresh is performed while the SDRAM is not being accessed.
The Auto Refresh interval is programmable.
The Self Refresh function is also supported.
Note: The SDRAM address area is determined by the CS1 or CS2 setting of the memory controller. However, the number of
bus cycle states is controlled by the SDRAMC.