Dma Channel Assignments; Table 1-4. Dreq Line Assignments - Dell OptiPlex Gn Service Manual

Dell OptiPlex Gn and Gn+ Systems Service Manual
1-24
D
MA Channel Assignments

Table 1-4. DREQ Line Assignments

DREQ Line Used By/Available
DREQ0 Available
DREQ1 Available
DREQ2 Generated by super I/O controller to initiate DMA cycle for
attached diskette drive
DREQ3 Available
DREQ4 Generated by bus controller chip to activate second DMA
controller
DREQ5 Available
DREQ6 Available
DREQ7 Available
NOTES: The optional built-in NIC and built-in video controller are assigned available DMA
channels automatically during system start-up.
If the parallel port is in ECP mode, it uses one of the available DREQ lines.