Хост-контроллер USB2.0: список регистров

  BULK_CURRENT_ED_31_4

BulkCurrentED[31:4]


This is advanced to the next ED after the HC has served the present one.
HC continues processing the list from where it left off in the last Frame.
When it reaches the end of the Bulk list, HC checks the ControlListFilled of HcControl.
If set, it copies the content of HcBulkHeadED to HcBulkCurrentED and clears the bit.
If it is not set, it does nothing.
HCD is only allowed to modify this register when the BulkListEnable of HcControl is cleared.
When set, the HCD only reads the instantaneous value of this register.
This is initially set to zero to indicate the end of the Bulk list.

  BULK_CURRENT_ED_3_0

BulkCurrentED[3:0]
Because the general TD length is 16 bytes, the memory structure for the TD must be aligned to a 16-byte boundary.
So the lower bits in the PCED, through bit 0 to bit 3 must be zero in this field.

HCD (HC)

Команда U-Boot для чтения регистра

Bit fields structure

typedef union  o_hcbulkcurrented
{
  struct
  {
   unsigned bulk_current_ed_3_0 : 4;
   unsigned bulk_current_ed_31_4 : 28;
  } b;
   unsigned long w;
} O_HcBulkCurrentED