Configurable Machine State
MMCDSR:
Mode Control and Diagnostic Status Register
(2101 8048)
--------------------------------------------------------
31:
Fast Diagnostic Mode (FDM)
0 = disabled* - diagnostic use only
30: FDM Second pass
0 = disabled* - diagnostic use only
29: Diagnostic Checkbit mode
0 = disabled* - diagnostic use only
28: QBus on I01
0 = QBus on IO2*
27: Enable soft error log (NDAL & memory related)
0 = disabled* - OpenVMS enables this
26: Flush BCache
0 = don’t flush*
24:17: Memory diagnostic check bits
0 - meaningful only in diagnostic check mode* (may or
may not be read as 0)
8:7: NDAL Timeout Scaler
00 = 2600 cycles* - maximum, to preserve timeout order
6: Disable memory error
0 = memory errors deteted and corrected*
5:
Refresh interval timer select
0 = 328 cycles* (Model 500A, 600A, 700A)
4:2: Force wrong parity on NDAL transactions
0 = off* - diagnostic use only
1: Disable memory refresh
0 = memory refreshed*
0: Force refresh
0 = normal refresh*
MOAMR:
O-bit Address and Mode Register
(2101 804C)
--------------------------------------------
16: Ignore O-bit mode
0 = O-bits checked*
15: Disable O-bit error
0 = O-bit errors detected*
14:6: O-bit segment address (0*) - meaningful only during
O-bit data register access
5:3: O-bit mask (0*) - meaningful only during O-bit data
register access
2:0: O-bit operation mode
000 = reconstruction mode* - meaningful only during
O-bit data register access
Configurable Machine State E–3
