SH7713 Datasheet, PDF (739/904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 19 Ethernet Controller Direct Memory Access Controller (E-DMAC)
Initial
Bit
Bit Name Value R/W Description
29
TFP1
0
R/W Transmit Frame Position 1, 0
28
TFP0
0
R/W Indicates whether information of the corresponding
descriptor represents information about the start,
middle, or end of the transmit frame.
00: The information of the descriptor represents
information about the middle of the frame.
01: The information of the descriptor represents
information about the end of the frame.
10: The information of the descriptor represents
information about the start of the frame.
11: The information of the descriptor represents all
information about the frame (single-frame/single-
descriptor (single-buffer)).
Reference:
When one frame is divided for use, the method of
specifying this bit for a descriptor row according to the
number of divisions is described below.
[For single-frame/single-descriptor operation]
First descriptor: TFP[1:0] = 11
[For single-frame/two-descriptor operation]
First descriptor: TFP[1:0] = 10
Second descriptor: TFP[1:0] = 01
[For single-frame/three-descriptor operation]
First descriptor: TFP[1:0] = 10
Second descriptor: TFP[1:0] = 00
Third descriptor: TFP[1:0] = 01
When the number of divisions is large, a descriptor
row is configured by adding intermediate descriptors
with TFP[1:0] = 00.
Rev.1.50 Aug. 30, 2006 Page 699 of 860
REJ09B0288-0150