Download SH7760 Group USB Host Module Application Note
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HcControlCurrentED Register: The HcControlCurrentED register indicates the physical address of the current Control ED. 3 1 0 0 4 3 0 0 0 CCED Figure 2.22 HcControlCurrentED Register Table 2.16 HcControlCurrentED Register Read/Write Key Reset HCD HC Description CCED 0h R/W R/W ControlCurrentED This field indicates a pointer of the current ED. This pointer is advanced to the next ED after serving the present one. When it reaches the end of the Control list, HC checks the ControlListFilled of in HcCommandStatus. If set, it copies the content of HcControlHeadED to HcControlCurrentED and clears the bit. If not set, it does nothing. HCD is allowed to modify this register only when the ControlListEnable of HcControl is cleared. When set, HCD only reads the instantaneous value of this register. HcBulkHeadED Register: The HcBulkHeadED register indicates the physical address of the first ED of the Bulk list. 3 1 0 0 4 3 0 0 0 BHED Figure 2.23 HcBulkHeadED Register Table 2.17 HcBulkHeadED Register Read/Write Key Reset HCD HC Description BHED 0h R/W R BulkHeadED HC traverses the Bulk list starting with the HcBulkHeadED pointer. HcBulkCurrentED Register: The HcBulkCurrentED register indicates the physical address of the current Bulk ED. Rev. 1.00, 10/03, page 37 of 90