Micros Systems Workstation 4 LX Service Manual page 99

Note 6
The POST checks SDRAM by reading and writing 0xAA and 0x55 patterns to each
memory location. If the DIMM is not installed however, a POST error does not occur.
Instead, the workstation exhibits symptoms similar to that of a bad boot loader chip.
See Step 2 in the Operational Troubleshooting section. The unit appears to respond
when the power switch is pressed, but the Operator LED glows solid Amber, the
screen remains dark, and the beeper does not sound. (This is because the processor is
not running.)
Note 7
EEPROM U21 stores the previous power management state and other information.
The POST attempts to access this device and if a problem is encountered, a failure is
reported. This is likely a defective EEPROM, or perhaps a problem with the Super IO
device that accesses it.
Note 8
This error indicates a problem was found on the PCI Bus and could point to any of the
following PCI bus devices.
• Ethernet Controller and Serial EEPROM
• USB Controller
• TFT Video Controller
• IDE Controller
• Audio Controller
• Mini-PCI Adapter XBRD68 - Requires Boot Loader Version 2.0.15.
The Mini-PCI Adapter Card XBRD68 appeared in 2006 to replace the PCMCIA
adapter card XBRB37. The Mini-PCI Wireless card is part of wireless kit for the
original Workstation 4.
If installed on a Workstation 4 System Board running a boot loader version prior to
2.0.15, the Mini-PCI Adapter causes a PCI Bus POST error because the older boot
loader does not recognize it as a valid PCI device. MD0011-012 describes how to
obtain boot loader version 2.0.15 and install it on the unit.
Workstation 4 and 4 LX Field Service Guide
WS4 Troubleshooting
POST Errors
3-13