7677ref.exe Model 76/77 Reference Disk v3.10 (zipped image)
U76 This can be either a N82077AA (90 and 95) or it can be National Semiconductor PC8477AV-2 floppy controller. A few systems have a 82077SL controller, PLUS U65 System EPROM 39G3299 is soldered directly to the planar (no PLCC socket needed).
There were several versions of the "Bermuda" board:
Bermuda Riser Cards
Bermuda 76 Riser FRU 87F4833
The 76i bus adapter support (individual FRU) is 61G2289. FRU 87F4833 is for the bracket alone.
Bermuda 77 Riser FRU 87F4836
The separate riser card (riveted onto bracket) is FRU 87F4836. My HMM has the bracket/riser as FRU 87F4836. The bracket/riser is marked with a sticker as P/N 39G2063
If you look closely at the 9577 planar you will find some SMD transistor "of the bigger kind" and some stuff that looks like "auto-termination". In addition the onboard SCSI adapter of the "Spock-Prime" is described as "SCSI-2 compliant"... which extends on the command set in the first place, the enhanced SCSI translation and on the electric interface as well I think. But not on the speed of course, which is 5 MB/s SCSI-1 standard.
From Peter Wendt:
I tried running the machine with a DX4-33/100 in 2x mode (jumper on interposer), which is known to even work at 50MHz input clock. No go. The cursor in the phase before memory count seems to blink a bit faster ... but then the machine hangs with I999-error after the count. Configuring it properly and *then* swapping the oscillator (which is a bit tricky) did not work either - ran into a solid I999 0022 (invalid IML). Restoring system partition from diskettes also failed.
Conclusion: overclocking isn't a good idea, at least not with this. Any other experiences?
Bermuda BVE Slot
On the 9576, Slot #1 is the BVE Slot, Slot #3 is the AVE slot.
Bermuda Planar ADF
Serial Port One: Choices are Serial 1 through Serial 16, or disabled. Standard interrupt levels are IRQ 4 for serial 1 and IRQ 3 for any other serial level.
Serial Port Two: Choices are Serial 1 through Serial 16, or disabled. Standard interrupt levels are IRQ 4 for serial 1 and IRQ 3 for any other serial level.
Parallel Port: Choices are Parallel
1 through 4 or disabled.
PARALLEL 1 (03bc-03bf 1278-127b int 7), 2 (0378-037b int 7), 3 (0278-027b int 7), 4 (1378-137b int 7), Disabled
Parallel Port DMA Arbitration Levels:
SCSI Address (ID): ID of the built-in SCSI controller. Choices are ID7 through ID0. Under normal circumstances, select <7>.
SCSI I/O Address: Select: I/O address
of built-in SCSI controller.
SCSI Fairness On/Off: Choices are On or Off. Bus Arbitration Fairness controls whether the adapter will release control of the bus when it has been using it exclusively. Under normal circumstances, select <On>.
SCSI DMA Arbitration Level: Choices are Level 1, 3, 5 through E. Selecting an arbitration level allows only this device to use the value.
ADP Fields (System determined)
Alternate Processor: Type of CPU installed in alternate processor socket on system board.
Current System Speed: Current speed of the system, 25MHz or 33MHz.
System Board: System board type
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