Table 7-52. Sconfigx Register; Table 7-53. Sconfigx Fields; Static Memory Configuration Register (Sconfigx) - Sharp LH79524 User Manual

External Memory Controller

7.5.2.21 Static Memory Configuration Register (SCONFIGx)

The Static Memory Configuration Registers are used to configure the static memory
configuration.
These registers must only be modified during system initialization, or when there are
no current or outstanding transactions. Software can ensure that there are no current or
outstanding transactions by waiting until the memory controller is idle, then entering
Low-Power Mode (CONTROL:MODE = 1), or Disable Mode (CONTROL:ENABLE = 0).
When in these two modes, external memory access is not allowed, ensuring that
changing parameters will not corrupt external data. Low-Power Mode automatically
refreshes SDRAM; Disable Mode requires commanding the SDRAM to Self Refresh
(DYNMCTRL:SR = 1) prior to entering Disable.
BIT
FIELD
RESET
TYPE
BIT
FIELD
RESET
TYPE
ADDR
NOTES:
1. The reset value for nCS1 changes depending on what byte lane boot state is selected. If nBLE0 isn't driven
externally at reset, reset value will be 0. Other chip selects always have a reset value of 0.
2. The reset value for nCS1 changes accordingly to what boot mode width is selected. If nBLE2 and nBLE1
aren't driven externally at reset, system will boot in 16-bit mode, with MW resetting to 0b01. Other chip
selects always have a reset value of 0b00.
BITS NAME
31:21
20
19
18:9
7-52

Table 7-52. SCONFIGx Register

31 30 29 28 27
0 0 0 0 0
RO RO RO RO RO
15 14 13 12 11
///
0 0 0 0 0
RW RW RW RW RW

Table 7-53. SCONFIGx Fields

/// Reserved Reading returns 0. Write the reset value.
Write Protect
P
1 = Write protected
0 = Not Write protected
Buffer Enable
B
1 = Read and write buffer enabled
0 = Read and write buffer disabled
/// Reserved Reading returns 0. Write the reset value.
26 25 24 23
///
0 0 0 0
RO RO RO RO
10 9 8 7
1
EW BLS
0 0 0 0
RW RW RW RW
0xFFFF1000 + 0x200 for SCONFIG0
0xFFFF1000 + 0x220 for SCONFIG1
0xFFFF1000 + 0x240 for SCONFIG2
0xFFFF1000 + 0x260 for SCONFIG3
FUNCTION
Version 1.0
LH79524/LH79525 User's Guide
22 21 20 19 18
P B
0 0 0 0 0
RO RO RW RW RW
6 5 4 3 2
PC /// PM ///
0 0 0 0 0
RW RW RW RW RW
17 16
///
0 0
RW RW
1 0
2
MW
0 0
RW RW