Samsung S5PC100 User Manual page 954

S5PC100 USER'S MANUAL (REV1.0)
7.4 DESCRIPTOR TABLE
Figure 8.12-15 shows the definition of 32-bit Address Descriptor Table. One descriptor line consumes 64-bit (8-
byte) memory space. Attribute is used to control descriptor. 3 action symbols are specified. "Nop" operation skips
current descriptor line and fetches next one. "Tran" operation transfers data designated by address and length
field. "Link" operation is used to connect separated two descriptors. The address field of link points to next
Descriptor Table. The combination of Act2=0 and Act1=1 is reserved and defined the same operation as Nop. A
future version of controller may use this field and redefine a new operation. 32-bit address is stored in the lower
32-bit of 64-bit address registers. Address field shall be set on 32-bit boundary (Lower 2-bit is always set to 0) for
32-bit address descriptor table. Table 8.12-1 shows the definition of length field in the Descriptor Table.
Length Field
Figure 8.12- 15 32-bit Address Descriptor Table
Table 8.12- 1 ADMA Length Field
0000h
0001h
0002h
......
FFFFh
SD/MMC CONTROLLER
Value of Length
65536 bytes
1 byte
2 bytes
......
65535 bytes
8.12-19