LSI Logic Confidential
Clock and Power Registers
16-3
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
16.1 Clock and Power Registers
All registers shown in this section are clocked by the CLKCTRL_CLK and
are NOT disabled unless the Main PLL is powered down.
Internal Clock Control Register
Cbus Address: 0xC20008
DLL Test
18
Enables DLL test mode when set. Should not be set by
software. This field is reset to zero.
SDRAM Stop
17
SDRAM Stop. When software writes a one to this bit,
pending SDRAM transactions are completed and the
sdrams are placed in standby-refresh power down mode.
Before setting this bit software must stop all internal DMA
operations or the chip will hang. After setting this bit, the
SPARC processors must only access the master or CBus
address space. Software should poll this register until this
bit reads as one to be sure that the sdram is actually
stopped. When software writes zero to this bit (and the
bit is set), the sdrams are taken out of standby refresh
mode. Software should poll this register until this bit
reads as zero to be sure that the sdram is actually
enabled. The SDRAMs should not be enabled until the
the internal clock is stable (1 ms after reset or frequency
change) and the DLL has been reset (10 ms after
reset-DLL is set). This bit is reset to one (SDRAM
disabled). Before performing normal accesses after a
power on reset, the drams must be initialized by setting
the DRAM clock control register, followed by the DRAM
configuration register 1 msec later (see DRAM interface
specification). This field is reset to one
31
20
19
18
17
16
Reserved DLL Test
SDRAM
Stop
SD
Mode
15
14
12
11
7
6
5
4
2
1
0
SD
Mode
Test Mode
XCO Adj
ClkO
Src
CkISrc
27
N
P
reset-
DLL
Содержание DMN-8600
Страница 14: ...LSI Logic Confidential xiv Contents Copyright 2001 2002 by LSI Logic Corporation All rights reserved ...
Страница 18: ...LSI Logic Confidential xviii Copyright 2001 2002 by LSI Logic Corporation All rights reserved ...
Страница 64: ...LSI Logic Confidential 7 6 Memory Mapping Copyright 2001 2002 by LSI Logic Corporation All rights reserved ...