Revision 1.1
49
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G
3.0
The General Configuration Block (GCB) includes registers
for:
General Configuration Block
Pin Multiplexing and Miscellaneous Configuration
WATCHDOG Timer
High-Resolution Timer
Clock Generators
A selectable interrupt is shared by all these functions.
3.1
Registers of the GCB are mapped in a 64-byte address
range which is mapped to I/O space. These registers are
physically connected to the internal Fast-PCI bus, but do
CONFIGURATION BLOCK ADDRESSES
not have a register block in PCI configuration space (i.e.,
they do not appear to software as PCI registers).
After system reset, the Base Address register is located at
I/O address 02EAh. This address can be used only once.
Before accessing any PCI registers, the BOOT code must
program this 16-bit register to the I/O base address for the
General Configuration Block registers. All subsequent
writes to this address, are ignored until system reset.
Note:
Location of the General Configuration Block cannot
be determined by software. See the
SC1100 Infor-
mation Appliance On a Chip device errata
docu-
ment.
Reserved bits in the General Configuration block should
read as written unless otherwise specified.
Table 3-1. Configuration Space Register Map
Offset
+0
+1
+2
+3
00h
WATCHDOG Timeout (WDTO)
WATCHDOG Configuration (WDCNFG)
04h
WATCHDOG Status
(WDSTS)
Reserved
08h
TIMER Value (TMVALUE)
0Ch
TIMER Status (TMSTS)
TIMER Config
(TMCNFG)
Reserved
10h
Maximum Core Clock
Multiplier (MCCM)
Reserved
PLL Power Control
(PPCR)
Reserved
14h
Reserved
18h
Clocks: PLL3C
1Ch
Reserved
Reserved
Core Clock Frequency (CCFC)
20h
Reserved
24h
28h
2Ch
30h
Pin Multiplexing (PMR)
34h
Miscellaneous Configuration (MCR)
38h
Interrupt Selection
(INTSEL)
Reserved
3Ch
IA On a Chip ID (IID)
Revision (REV)
Configuration Base Address (CBA)