Specifications

AMD Geode™ GeodeROM Functional Specification 95

System Time and Date 32087C

11.0System Time and Date

GeodeROM supports a majority of the standard system functions listed in Table 11-1.

11.1 INT 1Ah Time and Date Functions Descriptions

This section lists those INT 1Ah functions supported in GeodeROM, the parameters that system software supplies to each

INT 1Ah function, and the values each function returns.

11.1.1 Function 00h - Get System Time Status

Description:

Returns the 4-byte count of the number of timer ticks that have occurred since midnight. The value is maintained in the

BIOS Data Area (40:6C) (Refer to Section 6.4.1 “BIOS Data Area (BDA)” on page 62 for information on BDA.) It also

checks whether the rollover byte has been set (stored in location 40:70) and returns appropriately.

Passed:

Table 11-1. INT 1Ah Time and Date Functions

Function Number/Name Page Number

Function 00h - Get System Time Status 95

Function 01h - Set System Time 96

Function 02h - Get Real-Time Clock Time Status 96

Function 03h - Set Real-Time Clock Time 97

Function 04h - Get Real-Time Clock Date Status 97

Function 05h - Set Real-Time Clock Date 98

Function 06h - Set Real-Time Clock Alarm 98

Function 07h - Cancel Real-Time Clock Alarm 98

Function 09h - Get Real-Time Clock Alarm Status 99

Function 0Ah - Read System Day Counter 99

Function 0Bh - Set System Day Counter 99

Function 0Eh - Get Real-Time Clock Date/Time Alarm and Status 100

Function 0Fh - Initialize Real-Time Clock 100

Parameter Description

AH 00h