Theory of Operation Chapter 6
GPIB-1014 User Manual 6-6 © National Instruments Corporation
Enabling the Release On Request feature. Writing a 0 to this bit (ROR*) enables the Release
On Request feature while writing a 1 disables the Release On Request feature. This bit is set
to 1 during reset or power up. This bit is used by the DTB Requester circuitry.
Selecting the direction of the DMA transfer. Writing a 1 to this bit (DIR) indicates that the
transfer direction is from GPIB to VMEbus memory, while writing a zero indicates that the
direction is from VMEbus memory to the GPIB. This bit is used by the GPIB
Synchronization and Interrupt Control circuitry.
Writing any value to this register resets the circuitry which detects GPIB synchronization
after a DMA transfer. (For more information, see GPIB Synchronization and Interrupt
Control later in this chapter).