Section 10 Ethernet Controller Direct Memory Access Controller (E-DMAC)
Rev. 2.00 Mar 09, 2006 page 423 of 906
REJ09B0292-0200
10.2.3
E-DMAC Receive Request Register (EDRRR)
The E-DMAC receive request register issues receive directives to the E-DMAC.
Bit:
31
30
29
. . .
11
10
9
8
—
—
—
. . .
—
—
—
—
Initial value:
0
0
0
. . .
0
0
0
0
R/W:
R
R
R
. . .
R
R
R
R
Bit:
7
6
5
4
3
2
1
0
—
—
—
—
—
—
—
RR
Initial value:
0
0
0
0
0
0
0
0
R/W:
R
R
R
R
R
R
R
R/W
Bits 31 to 1—Reserved: These bits are always read as 0. The write value should always be 0.
Bit 0—Receive Request (RR): When 1 is written to this bit, the E-DMAC reads a descriptor, and
then transfers receive data to the buffer in response to receive requests from the EtherC.
Bit 0: RR
Description
0
After frame reception is completed, the receiver is disabled
1
A receive descriptor is read, and transfer is enabled
Notes: In order to receive a frame in response to a receive request, the receive descriptor active
bit in the receive descriptor must be set to “active” beforehand.
1. When the receive request bit is set, the E-DMAC reads the relevant receive descriptor.
2. If the receive descriptor active bit in the descriptor has the “active” setting, the E-DMAC
prepares for a receive request from the EtherC.
3. When one receive buffer of data has been received, the E-DMAC reads the next
descriptor and prepares to receive the next frame. If the receive descriptor active bit in
the descriptor has the “inactive” setting, the RR bit is cleared and operation of the
receive DMAC is halted.
Summary of Contents for SH7616
Page 10: ...Rev 2 00 Mar 09 2006 page x of xxvi ...
Page 132: ...Section 2 CPU Rev 2 00 Mar 09 2006 page 106 of 906 REJ09B0292 0200 ...
Page 568: ...Section 12 16 Bit Free Running Timer FRT Rev 2 00 Mar 09 2006 page 542 of 906 REJ09B0292 0200 ...
Page 582: ...Section 13 Watchdog Timer WDT Rev 2 00 Mar 09 2006 page 556 of 906 REJ09B0292 0200 ...
Page 706: ...Section 16 Serial I O SIO Rev 2 00 Mar 09 2006 page 680 of 906 REJ09B0292 0200 ...
Page 820: ...Section 19 Pin Function Controller PFC Rev 2 00 Mar 09 2006 page 794 of 906 REJ09B0292 0200 ...
Page 932: ...Appendix D Package Dimensions Rev 2 00 Mar 09 2006 page 906 of 906 REJ09B0292 0200 ...
Page 935: ...SH7616 Hardware Manual ...