Rainbow Electronics AT89C51SND1C - Manual (Page 101)

101
AT8xC51SND1C
4109E–8051–06/03
Table 93. USBIEN Register
USBIEN (S:BEh) – USB Global Interrupt Enable Register
Reset Value = 0001 0000b
Table 94. UEPNUM Register
UEPNUM (S:C7h) – USB Endpoint Number
Reset Value = 0000 0000b
7 6 5 4 3 2 1 0
- - EWUPCPU EEORINT ESOFINT - - ESPINT
Bit
Number
Bit
Mnemonic Description
7 - 6 -
Reserved
The value read from these bits is always 0. Do not set these bits.
5 EWUPCPU
Wake Up CPU Interrupt Enable Bit
Set to enable the Wake Up CPU interrupt.
Clear to disable the Wake Up CPU interrupt.
4 EEOFINT
End Of Reset Interrupt Enable Bit
Set to enable the End Of Reset interrupt. This bit is set after reset.
Clear to disable End Of Reset interrupt.
3 ESOFINT
Start Of Frame Interrupt Enable Bit
Set to enable the SOF interrupt.
Clear to disable the SOF interrupt.
2 - 1 -
Reserved
The value read from these bits is always 0. Do not set these bits.
0 ESPINT
Suspend Interrupt Enable Bit
Set to enable Suspend interrupt.
Clear to disable Suspend interrupt.
7 6 5 4 3 2 1 0
- - - - - - EPNUM1 EPNUM0
Bit
Number
Bit
Mnemonic Description
7 - 2 -
Reserved
The value read from these bits is always 0. Do not set these bits.
1 - 0 EPNUM1:0
Endpoint Number Bits
Set this field with the number of the endpoint which should be accessed when
reading or writing to registers UEPSTAX, UEPDATX, UBYCTX or UEPCONX.