The 82408667-001 is the current PROM/RAM board for the Multifunction Controller. This card combines the PROM of the earlier 82408443-004 and the 24K RAM of the 82408443-003 onto a single card.

This card resides in PROM slot 7, to the right of the processor, unless the backplane is 'ISSUE 1'. In this case the ROM/RAM board must be put in slot 4 (RAM) just to the right of the hiway boards. This is a requirement with 'ISSUE 1' so the memory backup battery can be kept charged. The backplane issue number is printed on the lower right corner of the backplane if it is a 'ISSUE 2' or 'ISSUE 3'. 'ISSUE 1' was not printed on the backplane.

The 82408667-001 24K RAM card uses battery (Old Style) 82408060-001 or new style 38002931-100 to maintain its RAM memory for up to 50 hours when power to the backplane is off.