Amiga Boot Sequence After getting a number of inquiries from fellow Amiga users about what

---
Master Index Current Directory Index Go to SkepticTank Go to Human Rights activist Keith Henson Go to Scientology cult

Skeptic Tank!

Amiga 'Boot' Sequence After getting a number of inquiries from fellow Amiga users about what's wrong with their Amigas when their Caplock key starts flashing, or, why the screen flashed odd colors, I decided to create this file. The Amiga goes through a rather elaborate startup sequence which is a series of diagnostic tests the Amiga goes through during each 'cold' or 'warm' boot. The following is a list of what happens during each and every 'boot': 1. Clear all old data in RAM 2. Disable DMA and interrupts 3. Clear the screen 4. Check hardware (is the 680x0 working?) 5. Change screen color indicating pass/fail 6. Perform checksum test of all ROMs 7. Change screen color indicating pass/fail 8. Begin system startup 9. Check RAM at $C0000..move SYSBASE there 10. Test CHIP RAM 11. Change screen color indicating pass/fail 12. Check if software is coming in OK 13. Change screen color indicating pass/fail 14. Set up CHIP RAM to receive data 15. Link libraries 16. Check for any additional RAM and link it 17. Turn on DMA and interrupts 18. Start default task 19. Check processor and MMU type 20. Check for an Exception (processor error) 21. If found, do a reset 22. If not, normal 'boot' As these tests are running, the Capslock key will normally 'flash' once, and the screen will cycle colors. The chart below used in conjunction with the above steps indicates both a 'normal' and an 'abnormal' boot. NORMAL Fault Condition Sreen color: Dark Grey Red (indicates error in ROM) Light Grey Green (error in CHIP RAM) White Blue (error in a Custom Chip) Yellow (680x0 found an error) Capslock Key: Stays on for several secs One blink (ROM checksum failed) Two blinks (RAM test failed) Three blinks (Whatchdog timer) Four blinks (A short exists between 2 lines or one of the special keys) Please note that the capslock 'blinks' are short in duration (about one second) and that your screen colors may falsely indicate a problem when you do a 'warm' boot depending on what state the Amiga was in before the warm boot. Its best to watch for these diagostic errors upon initial startup. If your Amiga exhibits any of these errors frequently, you should take it to an Authorised Service Center for service. The most common error you will encounter is that you'll see a bright green screen at the initial boot..this usually indicates that an addon RAM board is not seated in its socket properly. Try reseating it before you take it all to your dealer. You may save yourself some money;) X-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-X Another file downloaded from: NIRVANAnet(tm) & the Temple of the Screaming Electron Jeff Hunter 510-935-5845 Rat Head Ratsnatcher 510-524-3649 Burn This Flag Zardoz 408-363-9766 realitycheck Poindexter Fortran 415-567-7043 Lies Unlimited Mick Freen 415-583-4102 Specializing in conversations, obscure information, high explosives, arcane knowledge, political extremism, diversive sexuality, insane speculation, and wild rumours. ALL-TEXT BBS SYSTEMS. Full access for first-time callers. We don't want to know who you are, where you live, or what your phone number is. We are not Big Brother. "Raw Data for Raw Nerves" X-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-X

---

E-Mail Fredric L. Rice / The Skeptic Tank