Acer Altos G710 Altos G710 Service Guide - Page 88

Checkpoint Diagnostic LED Decoder G=Green, R=Red, A=Amber MSB LSB Description 37 OFF G A A Displaying sign-on message, CPU information, setup key message, and any OEM specific information. 38 G OFF R R Initializes different devices through DIM. See DIM Code Checkpoints section of document for more information. 39 G OFF R A Initializes DMAC-1 and DMAC-2. 3A G OFF A R Initialize RTC date/time. 3B G OFF R A Test for total memory installed in the system. Also, Check for DEL or ESC keys to limit memory test. Display total memory in the system. 3C G G R R Mid POST initialization of chipset registers. Detect different devices (Parallel ports, serial ports, and coprocessor 40 OFF R OFF OFF in CPU, ... etc.) successfully installed in the system and update the BDA, EBDA...etc. 50 OFF R OFF R Programming the memory hole or any kind of implementation that needs an adjustment in system RAM size if needed. 52 OFF R G R Updates CMOS memory size from memory found in memory test. Allocates memory for Extended BIOS Data Area from base memory. 60 OFF R R OFF Initializes NUM-LOCK status and programs the KBD typematic rate. 75 OFF A R A Initialize Int-13 and prepare for IPL detection. 78 G R R R Initializes IPL devices controlled by BIOS and option ROMs. 7A G R A R Initializes remaining option ROMs. 7C G A R R Generate and write contents of ESCD in NVRam. 84 R G OFF OFF Log errors encountered during POST. 85 R G OFF G Display errors to the user and gets the user response for error. 87 R G G G Execute BIOS setup if needed / requested. 8C A G OFF OFF Late POST initialization of chipset registers. 8D A G OFF G Build ACPI tables (if ACPI is supported) 8E A G G OFF Program the peripheral parameters. Enable/Disable NMI as selected 90 R OFF OFF R Late POST initialization of system management interrupt. A0 R OFF R OFF Check boot password if installed. A1 R OFF R G Clean-up work needed before booting to operating system. Takes care of runtime image preparation for different BIOS modules. A2 R OFF A OFF Fill the free area in F000h segment with 0FFh. Initializes the Microsoft IRQ Routing Table. Prepares the runtime language module. Disables the system configuration display if needed. A4 R G R OFF Initialize runtime language module. A7 R G A G Displays the system configuration screen if enabled. Initialize the CPU's before boot, which includes the programming of the MTRR's. A8 A OFF R OFF Prepare CPU for operating system boot including final MTRR values. A9 A OFF R G Wait for user input at config display if needed. AA A OFF A OFF Uninstall POST INT1Ch vector and INT09h vector. Deinitializes the ADM module. AB A OFF A G Prepare BBS for Int 19 boot. AC A G R OFF End of POST initialization of chipset registers. B1 R OFF R A Save system context for ACPI. 00 OFF OFF OFF OFF Passes control to OS Loader (typically INT19h). Chapter 4 80