Specifications
AMD Geode™ GeodeROM Functional Specification 143
System Services
32087C
12.1.10.12 Subfunction 20h - Get SCxxxx External Clock Speed
Description:
Returns the value of the single chip device’s clock speed in MHz.
Passed:
Related Functions:
None.
Returns:
12.1.10.13 Subfunction 21h - Get SCxxxx Device Type
Description:
Returns the value of the single chip device’s number in the system (i.e., SC1100, SC1200, SC1201, SC2200,
SC3200).
Passed:
Returns:
Related Functions:
None.
Parameter Description
AX BE20h
BX 4E53h (= ‘NS’)
Parameter Description
AX Clock speed (MHz)
CF 0 = Success
1 = Failure
Parameter Description
AX BE21h
BX 4E53h (= ‘NS’)
CX 00h = Returns CPU type that GeodeROM was built with
01h = Returns CPU type reported by F5 60h
02h = Returns CPU type reported by CPU straps
Parameter Description
EBX Chip ID
CF 0 = Success
1 = Failure