FDC37M81 SMSC [SMSC Corporation], FDC37M81 Datasheet - Page 148

• Manufacturer Part Number: FDC37M81
• Description: PC98/99 Compliant Enhanced Super I/O Controller with Keyboard/Mouse Wake-Up
• Manufacturer: SMSC [SMSC Corporation]

Note:
Note:
Note 1: The DMA (0x74) default address for logical device 0 (FDD) is 0x02 and for logical device 3 is
DMA Channel
Select
Default = 0x04
or 0X02
(Note 1)
on VCC POR,
VTR POR,
SOFT RESET
and HARD
RESET
NAME
A DMA channel is activated by setting the DMA Channel Select register to [0x01-0x03] AND :
For the FDC logical device by setting DMAEN, bit D3 of the Digital Output Register.
For the PP logical device in ECP mode by setting dmaEn, bit D3 of the ecr.
DMAREQ pins must tri-state if not used/selected by any Logical Device. Refer to Note A.
0x04.
Table 57 - DMA Channel Select Configuration Register Description
REG INDEX
0x74 (R/W)
Bits[2:0] select the DMA Channel.
0x00= Reserved
0x01= DMA1
0x02= DMA2
0x03= DMA3
0x04-0x07= No DMA active
148
DEFINITION
STATE
C