NEC Network Controller uPD98502 - Manual (Page 349)

CHAPTER 6 USB CONTROLLER
Preliminary User’s Manual S15543EJ1V0UM 349
(1) Reception in EndPoint0, EndPoint6
Same processing is executed without relations in receive mode in EndPoint0, EndPoint6 every time.
Figure 6-16. Data Receiving in EndPoint0, EndPoint6
D 0
µ P D 9 8 5 0 2
B uffe r
D irec to ry
D 1 D 2 D 3
D 0
D 1
D 2
R x In dicatio n
R x In dicatio n
R x In dicatio n
D 0
D 3
R x In dicatio n
When USB Controller receives one USB packet, stores it in Data Buffer and write Rx indication to the Mailbox. USB
Controller updates the size field and Last field in Buffer Descriptor every USB packet before writing Rx Indication.
(2) EndPoint2, EndPoint4, normal mode
The processing in EndPoint2, EndPoint4 receive Normal mode is explained below.
Figure 6-17. EndPoint2, EndPoint4 Receive Normal Mode
D 0
µ P D 9 8 5 0 2
B uffe r
D irec to ry
D 1 D 2 D 3
D 0
D 1
D 2
R x In dicatio n
R x In dicatio n
R x In dicatio n
D 0
D 3
R x In dicatio n
When USB Controller receives one USB packet, stores it in Data Buffer and write Rx indication to the Mailbox. USB
Controller updates the size field and Last field in Buffer Descriptor every USB packet before writing Rx Indication.