Transmeta Crusoe TM5500, System Design Manual

Page: 12 / 130

July 17, 2002
12
Introduction and Naming Conventions
Note that some terms must be combined for a full description of system state (e.g. Working/Auto Halt vs.
Working/Quick Start). For more details on ACPI states, see the ACPI specification.
For information on timing requirements between states, see State Transition Timing Requirements on
page 42. Power specifications for each of the supported power management modes are provided in Chapter
3, Electrical Specifications in the Data Book .
1.3.2 Power Network Names
Transmeta’s reference schematics use a standard naming convention for power supply nets, provided in the
table below.
1.3.3 Signal Names
Transmeta’s reference schematics call out many signals which may be named slightly differently in hardware-
oriented documents such as the
Data Book . The following table illustrates the character conventions used in
the schematics:
S4 Suspend-to-Disk
(STD) Current processor state is suspended and saved to non-volatile disk.
All power supplies except _ALWAYS are off.
S5 Soft Off System is turned off. All power supplies except _ALWAYS are off.
Table 3: Power Net Naming Conventions
Convention Description
V_ name A switched voltage such as V_CPU_CORE, off during S3, S4, and S5
V n _ d _STR A voltage present in S3 (STR), off during S4 and S5
V n _ d A switched voltage at n.d volts, off during S3, S4, and S5
V_N n _ d A negative voltage at n.d volts, off during S3, S4, and S5
V n _ d _ALWAYS An always-on voltage, i.e. present in all ACPI sleep states
Table 4: Signal Naming Conventions
Character Description Example
# Denotes asserted low signals. Signal names without this suffix are
assumed to assert high. LOWSIG#
.., : Used to separate elements in a list. EIGHTBITBUS[7..0]
D[7:0]
/ Can be used to separate multiple uses of a pin. USEA/USEB
[ ] Delineates bus name from element list. EIGHTBITBUS[7..0]
Table 2: Supported ACPI System States (Continued)
ACPI State ACPI State Name Description