
IDT DMA Controller
PES32NT24xG2 User Manual
15 - 4
January 30, 2013
Notes
Figure 15.4 DMA Channel Addressing
1
The addressing operation consists of two loops. The inner loop performs linear addressing, while the
outer loop implements stride addressing (i.e., used for constant addressing as described later).
1.
The pseudo code in this figure does not support the SSSIZE or DSSIZE equal to zero case. See the text for
behavior.
Global Parameters
BCOUNT
Byte Count
Total number of bytes to transfer
Source Addressing Parameters
SADDR
Source Address
Starting source memory address
SSSIZE
Source Stride Size
Amount of data bytes to transfer in each source
stride (a value of zero indicates an infinite stride
size)
SSCOUNT
Source Stride Count
Number of times to execute the stride loop
SSDIST
Source Stride Distance
Stride distance in bytes (two’s complement repre-
sentation of a positive or negative number)
Destination Addressing Parameters
DADDR
Destination Address
Starting destination memory address
DSSIZE
Destination Stride Size
Amount of data bytes to transfer in each destination
stride (a value of zero indicates an infinite stride
size)
DSCOUNT
Destination Stride Count
Number of times to execute the stride loop
DSDIST
Destination Stride Distance
Stride distance in bytes (two’s complement repre-
sentation of a positive or negative number)
Table 15.1 DMA Channel Addressing Parameters
count = BCOUNT
addr = SADDR
for (j=0; j<SSCOUNT; ++j) {
for (i=0; i<SSSIZE; ++i) {
data = memRead(addr)
count = count - 1
if (count == 0) {
goto done
}
addr = addr + 1
}
addr = addr + SSDIST
}
count = BCOUNT
addr = DADDR
for (j=0; j<DSCOUNT; ++j) {
for (i=0; i<DSSIZE; ++i) {
memWrite(addr,data)
count = count - 1
if (count == 0) {
goto done
}
addr = addr + 1
}
addr = addr + DSDIST
}
(a) Source Addressing
(b) Destination Addressing
Содержание PCI Express 89HPES32NT24xG2
Страница 20: ...IDT Table of Contents PES32NT24xG2 User Manual x January 30 2013 Notes...
Страница 24: ...IDT List of Tables PES32NT24xG2 User Manual xiv January 30 2013 Notes...
Страница 28: ...IDT List of Figures PES32NT24xG2 User Manual xviii January 30 2013 Notes...
Страница 56: ...IDT PES32NT24xG2 Device Overview PES32NT24xG2 User Manual 1 20 January 30 2013 Notes...
Страница 100: ...IDT Switch Core PES32NT24xG2 User Manual 4 22 January 30 2013 Notes...
Страница 124: ...IDT Switch Partition and Port Configuration PES32NT24xG2 User Manual 5 24 January 30 2013 Notes...
Страница 128: ...IDT Failover PES32NT24xG2 User Manual 6 4 January 30 2013 Notes...
Страница 148: ...IDT Link Operation PES32NT24xG2 User Manual 7 20 January 30 2013 Notes...
Страница 164: ...IDT SerDes PES32NT24xG2 User Manual 8 16 January 30 2013 Notes...
Страница 170: ...IDT Power Management PES32NT24xG2 User Manual 9 6 January 30 2013 Notes...
Страница 196: ...IDT Transparent Switch Operation PES32NT24xG2 User Manual 10 26 January 30 2013 Notes...
Страница 244: ...IDT SMBus Interfaces PES32NT24xG2 User Manual 12 40 January 30 2013 Notes...
Страница 247: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 3 January 30 2013 Notes...
Страница 248: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 4 January 30 2013 Notes...
Страница 330: ...IDT Switch Events PES32NT24xG2 User Manual 16 6 January 30 2013 Notes...
Страница 342: ...IDT Multicast PES32NT24xG2 User Manual 17 12 January 30 2013 Notes...
Страница 344: ...IDT Temperature Sensor PES32NT24xG2 User Manual 18 2 January 30 2013 Notes...
Страница 384: ...IDT Register Organization PES32NT24xG2 User Manual 19 40 January 30 2013...
Страница 492: ...IDT Proprietary Port Specific Registers PES32NT24xG2 User Manual 21 44 January 30 2013 Notes...
Страница 588: ...IDT NT Endpoint Registers PES32NT24xG2 User Manual 22 96 January 30 2013 Notes...
Страница 710: ...IDT JTAG Boundary Scan PES32NT24xG2 User Manual 25 12 January 30 2013 Notes...
Страница 743: ...IDT Usage Models PES32NT24xG2 User Manual 26 33 January 30 2013 Notes...
Страница 744: ...IDT Usage Models PES32NT24xG2 User Manual 26 34 January 30 2013 Notes...