LCSR Programming Model

from the retry and the board does not lose its turn on the VMEbus. For this reason, it is recommended that this bit remain low.

NOELBBSY When this bit is high, the early release feature of bus busy feature on the VMEbus is disabled. The VMEchip2 drives BBSYlow whenever VMEbus ASis low. When this bit is low, the early release feature of bus busy feature on the VMEbus is not disabled.

DISMST When this bit is high, the VME LED on the MVME1x7P illuminates on assertion of Local Bus Reset or when the VMEchip2 ASIC is driving Local Bus Busy. When this bit is low, the VME LED on the MVME1x7P illuminates on assertion of Local Bus Reset, when the VMEchip2 is driving Local Bus Busy, or when the VMEchip2 is driving the VMEbus address strobe.

(The signal is also available at J2, the Remote Reset connector behind the front panel. This connector allows the Reset, Abort, and LED functions to be extended to the exterior of the enclosure containing the board.)

DISSRAM When this bit is high, the SRAM decoder in the VMEchip2 is disabled. When this bit is low, the SRAM decoder in the VMEchip2 is enabled. Because the SRAM decoder in the VMEchip2 is not used on the MVME1x7P, this bit must be set.

REVEROM This function is not used on the MVME1x7P. This bit must not be set.

MPIRQEN This function is not used on the MVME1x7P. This bit must not be set.

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Motorola MVME1X7P manual Lcsr Programming Model