NXP Semiconductors PXN2020 - Page 781

Media Local Bus (MLB)
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor 27-9
Offset: MLB_BASE + 0x0000 Access: User read/write
0123456 7 8 9101112131415
R
MDE LBM MCS[1:0]
0 MLK
MLE MHRE MRS
0000000
W
Reset0000000000000000
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
R 0 0000000
MDA[8:1]
W
Reset0000000000000000
Figure 27-2. Device Control Configuration Register (DCCR)
Table 27-8. DCCR Field Descriptions
Field Description
MDE MLB Device Enable. When set, enables the MLB Interface based on the other bits in the register.
0 MLB device disabled.
1 MLB device enabled.
LBM Loop-Back Mode Enable. When set, enables the loop-back testing of the MLB bus between logical channel 0 (RX)
and logical channel 1 (TX).
0 Loop-back mode disabled.
1 Loop-Back Mode Enabled.
MCS
[1:0]
MLB Clock Select. These field must be programmed by system software to reflect the MLBCLK speed.
00 256Fs: supports 8 quadlets per frame.
01 512Fs: supports 16 quadlets per frame.
10 1024Fs: supports 32 quadlets per frame.
11 Reserved.
MLK MLB Lock. When set, indicates that the MLB Port is synchronized to the incoming MLB frame. If MLK is clear
(unlocked), MLK is set after FRAMESYNC is detected at the same position for three consecutive frames. If MLK is
set (locked), MLK is cleared after not receiving FRAMESYNC at the expected time for two consecutive frames. While
MLK is set, FRAMESYNC patterns occurring at locations other than the expected one are ignored.
0 MLB device is not synchronized to the incoming MLB frame.
1 MLB device is synchronized to the incoming MLB frame.
MLE MLB Little Endian. This field determines how MLB quadlet based data is stored in system memory. For normal
operation, this bit should be set.
0 Little Endian mode.
1 Big Endian mode.
MHRE MLB Hardware Reset Enable. When set, enables hardware to automatically reset the MLB physical and link layer
logic upon the reception of either a global (SDCR[MDS] = 8’h0000) or device specific (SDCR[MDS] = DA) MlbReset
(FEh) System Command.
0 MLB device does not reset on reception of system reset command.
1 MLB device is reset on reception of system reset command.