13-4
DS785UM1
Copyright 2007 Cirrus Logic
SDRAM, SyncROM, and SyncFLASH Controller
EP93xx User’s Guide
1
3
1
3
13
the synchronous memory map. Refer to
to compare the memory space with
SROMLL=1 and SROMLL=0. bit can be used to reduce the number of memory segments
and it is
1. “AP” means Auto Precharge -- see SDRAM device’s data sheet
13.4 SDRAM Initialization
Following power on, each SDRAM device must be initialized before it can be used.
shows a general initialization sequence (refer to the SDRAM device’s data sheet to ensure
compatibility).
Table 13-3. Synchronous Memory Address Decoding
Sync
Device
Address
Pins
Muxing
Bank
Address
Pins
Address Pins
AD
15
AD
14
AD
13
AD
12
AD
11
AD
10
AD
9
AD
8
AD
7
AD
6
AD
5
AD
4
AD
3
AD
2
AD
1
AD
0
SDRAM
16 bit
data
Row and
Bank
A27
A26
A22
A21
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
A10
A9
Column
A27
A26
-
-
-
AP
1
A25
A24
A8
A7
A6
A5
A4
A3
A2
A1
SDRAM
32 bit
data
Row and
Bank
A27
A26
A23
A22
A21
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
A10
Column
A27
A26
-
-
-
AP
1
A25
A24
A9
A8
A7
A6
A5
A4
A3
A2
SFLASH
2K Page
Mode,
32 bit
data
Row and
Bank
A27
A26
A24
A23
A22
A21
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
Column
A27
A26
-
-
-
AP
1
A25
A10
A9
A8
A7
A6
A5
A4
A3
A2
SROM
512, 32
bit data
Row and
Bank
A27
A26
A22
A21
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
A10
A9
Column
A27
A26
-
-
-
-
A25
A24
A23
A8
A7
A6
A5
A4
A3
A2
SROM
look
alike, 16
bit data
Row and
Bank
A22
A21
A27
A26
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
A10
A9
Column
A22
A21
-
-
-
AP
1
A25
A24
A8
A7
A6
A5
A4
A3
A2
A1
SROM
look
alike, 32
bit data
Row and
Bank
A23
A22
A27
A26
A21
A20
A19
A18
A17
A16
A15
A14
A13
A12
A11
A10
Column
A23
A22
-
-
-
AP
1
A25
A24
A9
A8
A7
A6
A5
A4
A3
A2
Table 13-4. General SDRAM Initialization Sequence
Step
Action
Reason
1
Wait 100
μ
s
To allow SDRAM power and clocks to
stabilize
Summary of Contents for EP93 Series
Page 28: ...P 6 DS785UM1 Copyright 2007 Cirrus Logic Preface EP93xx User s Guide PP P ...
Page 162: ...5 36 DS785UM1 Copyright 2007 Cirrus Logic System Controller EP93xx User s Guide 55 5 ...
Page 576: ...15 18 DS785UM1 Copyright 2007 Cirrus Logic UART2 EP93xx User s Guide 1515 15 ...
Page 634: ...17 38 DS785UM1 Copyright 2007 Cirrus Logic IrDA EP93xx User s Guide 1717 17 ...
Page 648: ...19 6 DS785UM1 Copyright 2007 Cirrus Logic Watchdog Timer EP93xx User s Guide 1919 19 ...
Page 688: ...21 32 DS785UM1 Copyright 2007 Cirrus Logic I2S Controller EP93xx User s Guide 2121 21 ...
Page 790: ...27 20 DS785UM1 Copyright 2007 Cirrus Logic IDE Interface EP93xx User s Guide 2727 27 ...
Page 808: ...28 18 DS785UM1 Copyright 2007 Cirrus Logic GPIO Interface EP93xx User s Guide 2828 28 ...