Microid Research Microid Research MR-BIOS 20 East Main Street #6 ======================== Los Gatos, CA 95032 00 Cold-Boot Commences (Not Seen with Warm-Boot) 01 HOOK 00 OEM Specific, Typically Restores Chipset to Default 02 Disable Critical I/O: 6845s, 8237s, 765, and Parity Latches 03 ROM BIOS Checksum Test 04 Page Register Test (Ports 81-8F) 05 8042 (Keyboard Controller) Selftest 06 8237-slave/master, 8254-ch2/1, RTC-REG-F/A, 8259-master/slave 07 Memory Refresh Circuit test 08 Master (16 bit) DMA Controller Failure 08 Slave (8 bit) DMA Controller Failure 09 HOOK 01 OEM Specific, Typically Disables Cache, Shadow 0A Base 64K Memory Test - Beep Code Describes Failure 0A Memory Bank 0 Pattern Test Failure 0A Memory Bank 0 Parity Circuitry Failure 0A Memory Bank 0 Parity Error 0A Memory Bank 0 Data Bus Failure 0A Memory Bank 0 Address Bus Failure 0A Memory Bank 0 Block Access Read Failure 0A Memory Bank 0 Block Access Read/Write Failure 0b Master 8259 (Port 21) Failure 0b Slave 8259 (Port A1) Failure 0C 8259/IRQ tests - Beep Code Describes Failure 0C Master 8259 (Port 20) Interrupt Address Error 0C Slave 8259 (Port A0) Interrupt Address Error 0C 8259 (Port 20/A0) Interrupt Address Error 0C Master 8259 (Port 20) Stuck Interrupt Error 0C Slave 8259 (Port A0) Stuck Interrupt Error 0C System timer 8254 CH0/IRQ0 Interrupt Failure 0d 8254 Channel-0 Test and Initialization 0E 8254 Channel-2 (Speaker) Failure 0E 8254 OUT2 (Speaker Detect) Failure 0F RTC tests/inits: Init REG-B, Write/Readback CMOS-RAM, PIE Test 0F CMOS RAM Read/Write Test Failure 0F RTC Periodic Interrupt / IRQ8 Failure 10 Video Initialization and (Cold-Boot) Signon Message 11 CMOS Checksum Test 12 Keyboard Controller Failure 13 HOOK 02 OEM Specific 14 Size/Test Base Memory (Low 64K Already Done) 15 Perform 2nd Try KB Init, if Necessary 16 HOOK 03 Size/Test Cache, Other OEM Unique Code 17 A20 Gate Stuck in Asserted State 17 A20 Test Failure Due to 8042 Timeout 17 A20 Gate Stuck in Disabled State 18 Size/Test Extended Memory 19 HOOK 04 and Size/Test System Memory ("Special" OEM Memory) 19 Memory Parity Error 19 IO Channel Error 1A Real Time Clock (RTC) Settings are Invalid 1A Real Time Clock (RTC) is Not Updating 1b Serial Port Determination Off-board/On-board 1C Parallel Port Determination, Off-board/On-board 1d Coprocessor Determination/Initialization 1E Floppy Controller Test/Determination, CMOS Validation 1F Fixed Disk Controller Test/Determination, CMOS Validation 20 Rigorous CMOS Parameter Validation 21 Front-Panel Lock Check, Wait for User to Acknowledge Errors 22 Set NumLock, Password-Security Trap, Dispatch to Setup-Utility 23 HOOK 05 OEM Specific 24 Set Typematic Rate 25 Floppy Subsystem Initialization 26 Fixed Subsystem Initialization 27 ACK Errors, Set Primary Adaptor Video Mode 28 HOOK 06 OEM Specific, Typically Enables Shadow, Cache, Speed 29 Adaptor ROM Installation 2A ACK Errors, set Video Mode, Set DOS Time Variables From RTC 2b Enable Parity Checking and NMI 2C Set Low Stack, Install E000 ROM 2d ACK Errors, Set Primary Video Mode 2E HOOK 07 OEM Specific 2F Pass Control to INT19 (Boot Disk)