ALR BIOS Post Codes:

 01   CPU register test in progress 
 02   Real-time clock write/read failure 
 03   ROM BIOS checksum failure 
 04   Programmable internal timer failure (or no video card present) 
 05   DMA initialization failure 
 06   DMA page register write/read failure 
 08   RAM-refresh verification failure 
 09   1st 64KB RAM test in progress 
 0A   1st 64KB RAM chip or data line multi-bit failure 
 0B   1st 64KB RAM odd/even logic failure 
 0C   Address line failure 1st 64KB RAM 
 0D   Parity failure 1st 64KB RAM 
 10-1F   bit 0-15 64KB RAM failure 
 20   Slave DMA-register failure 
 21   Master DMA-register failure 
 22   Master-interrupt mask-register failure 
 23   Slave-interrupt mask-register failure 
 25   Interrupt vector loading in progress 
 27   Keyboard-controller test failure 
 28   RTC power failure and checksum calculation in progress 
 29   Real-time clock-configuration validation in progress 
 2B   Screen-memory test failure 
 2C   Screen-initialization failure 
 2D   Screen-retrace test failure 
 2E   Search believed operational on screen believed running with video ROM 
 30   Monochrome display believed operable 
 32   Color display (40 column) believed operable 
 33   Color display (80 column) believed operable