40.8.38 SDHC AHB Control Register

Table 40-42. Register Bit Attribute Legend
Symbol Description Symbol Description Symbol Description
R Readable bit HC Cleared by Hardware (Grey cell) Unimplemented
W Writable bit HS Set by Hardware X Bit is unknown at Reset
K Write to clear S Software settable bit
Name: ACR
Offset: 0x208
Reset: 0x00000000
Property: -

Bit 3130292827262524 
          
Access  
Reset  
Bit 2322212019181716 
          
Access  
Reset  
Bit 15141312111098 
          
Access  
Reset  
Bit 76543210 
   B1KBDISHNBRDIS  BMAX[1:0] 
Access R/WR/WR/WR/W 
Reset 0000 

Bit 5 – B1KBDIS 1kB Boundary Disable

Only significant when the xKBBoundary is not supported by the HMATRIX. Used for debug.

Bit 4 – HNBRDIS HNBREQ Disable

Used for debug to modulate the peripheral host interface bandwidth. Set to 1 to reduce the peripheral bandwidth.

Bits 1:0 – BMAX[1:0] AHB Maximum Burst

This field selects the maximum burst size in case of DMA transfer.

ValueNameDescription
0 INCR16

The maximum burst size is INCR16.

1 INCR8

The maximum burst size is INCR8.

2 INCR4

The maximum burst size is INCR4.

3 SINGLE

Only SINGLE transfers are performed.