Rainbow Electronics AT89C5131 - Manual (Page 136)

136
AT89C5131
4136A–USB–03/03
Table 87. UEPNUM Register
UEPNUM (S:C7h)
USB Endpoint Number
Reset Value = 00h
7 6 5 4 3 2 1 0
- - - - EPNUM3 EPNUM2 EPNUM1 EPNUM0
Bit Number Bit Mnemonic Description
7-4 -
Reserved
The value read from these bits is always 0. Do not set these bits.
3-0 EPNUM[3:0]
Endpoint Number
Set this field with the number of the endpoint which will be accessed when
reading or writing to, UEPDATX Register UEPDATX (S:CFh) USB FIFO Data
Endpoint X (X = EPNUM set in UEPNUM Register UEPNUM (S:C7h) USB
Endpoint Number), UBYCTLX Register UBYCTLX (S:E2h) USB Byte Count
Low Register X (X = EPNUM set in UEPNUM Register UEPNUM (S:C7h)
USB Endpoint Number), UBYCTHX Register UBYCTHX (S:E3h) USB Byte
Count High Register X (X = EPNUM set in UEPNUM Register UEPNUM
(S:C7h) USB Endpoint Number) or UEPCONX Register UEPCONX (S:D4h)
USB Endpoint X Control Register. This value can be 0, 1, 2, 3, 4, 5 or 6.