NEC Network Controller uPD98502 - Manual (Page 327)

CHAPTER 6 USB CONTROLLER
Preliminary User’s Manual S15543EJ1V0UM 327
6.2.19 U_RP0AR (USB Rx Pool0 Address Register)
This register indicates the start address of Buffer Directory which is currently used.
The way to set up Rx Pool is described at Section 6.6.3 Receive pool settings.
Bits Field R/W Default Description
31:0 Address R 0 Buffer Directory Address:
Register that indicates the start address of the first Buffer Directory in Pool0.
The V R 4120A can only read this register.
Buffer Directory addition is performed entirely using the USB Command
Register.
6.2.20 U_RP1IR (USB Rx Pool1 Information Register)
This register indicates the information of Receive Pool1.
The V R 4120A writes to this register only when the device is being initialized.
Bits Field R/W Default Description
31 Reserved R/W 0 Reserved for future use. Writes ‘0’s.
30:28 AL R/W 000 Alert Level:
Sets the warning level for Pool1. When the number of Buffer Directories
remaining in this pool equals the value set in this field, USB Controller sets
the RPA1 bit in the USB General Status Register1 to a ‘1’.
Writing N in this field is equivalent to specifying N x 4 (remaining number of
Buffer Directories = 4, 8, 12, …, 28). When 000 is written into this field, this
function is disabled and no notification is posted to the V
R
4120A.
27:16 Reserved R/W 0 Reserved for future use. Writes ‘0’s.
15:0 RNOD R 0 Remaining Number of Buffer Directory:
Indicates the number of Buffer Directories remaining in Pool1. The V
R
4120A
can only read this field.
Buffer Directory addition is performed entirely using the USB Command
Register.
6.2.21 U_RP1AR (USB Rx Pool1 Address Register)
This register indicates the start address of Buffer Directory which is currently used.
The way to set up Rx Pool is described at Section 6.6.3 Receive pool settings.
Bits Field R/W Default Description
31:0 Address R 0 Buffer Directory Address:
Register that indicates the start address of the first Buffer Directory in Pool1.
The V R 4120A can only read this register.
Buffer Directory addition is performed entirely using the USB Command
Register.