AT85C51SND3Bx
Table 126. UEINTX Register (bit addressable)
UEINTX (1.C8h) – USB Endpoint Interrupt Register
7
6
5
4
3
2
1
0
FIFOCON
NAKINI
RWAL
NAKOUTI
RXSTPI
RXOUTI
STALLI
TXINI
Bit
Bit
Number
Mnemonic Description
FIFO Control Bit
For OUT and SETUP Endpoint:
Set by hardware when a new OUT message is stored in the current bank, at the
same time than RXOUT or RXSTP.
Clear to free the current bank and to switch to the following bank. Setting by
software has no effect.
7
FIFOCON
For IN Endpoint:
Set by hardware when the current bank is free, at the same time than TXIN.
Clear to send the FIFO data and to switch the bank. Setting by software has no
effect.
NAK IN Received Interrupt Flag
Set by hardware when a NAK handshake has been sent in response of a IN
request from the host. This triggers an USB interrupt if NAKINE is sent.
6
5
NAKINI
Shall be cleared by software. Setting by software has no effect.
Read/Write Allowed Flag
Set by hardware to signal:
- for an IN endpoint: the current bank is not full i.e. the firmware can push data
into the FIFO,
RWAL
- for an OUT endpoint: the current bank is not empty, i.e. the firmware can read
data from the FIFO.
The bit is never set if STALLRQ is set, or in case of error.
Cleared by hardware otherwise.
This bit shall not be used for the control endpoint.
NAK OUT Received Interrupt Flag
Set by hardware when a NAK handshake has been sent in response of a
OUT/PING request from the host. This triggers an USB interrupt if NAKOUTE is
sent.
4
3
NAKOUTI
RXSTPI
Shall be cleared by software. Setting by software has no effect.
Received SETUP Interrupt Flag
Set by hardware to signal that the current bank contains a new valid SETUP
packet. An interrupt (EPINTx) is triggered (if enabled).
Shall be cleared by software to handshake the interrupt. Setting by software has
no effect.
This bit is inactive (cleared) if the endpoint is an IN endpoint.
Received OUT Data Interrupt Flag
Set by hardware to signal that the current bank contains a new packet. An
interrupt (EPINTx) is triggered (if enabled).
Shall be cleared by software to handshake the interrupt. Setting by software has
no effect.
RXOUTI /
KILLBK
2
Kill Bank IN Bit
Set this bit to kill the last written bank.
Cleared by hardware when the bank is killed. Clearing by software has no effect.
See Section “Abort” for more details on the Abort.
123
7632A–MP3–03/06