Datasheet

8−14
SLLS535E − April 2008TUSB6250
8.9.3 OEPCNFG_0: Output Endpoint-0 Configuration Register (XDATA at F003)
The OEPCNFG_0 register contains various bits used to configure and control this endpoint.
76543210
UBME NAK_INTE TOGLE RSV STALL USBIE RSV RSV
R/W R/W R/O R/O R/W R/W R/O R/O
BIT NAME RESET FUNCTION
1−0 RSV 00 Reserved = 00
2 USBIE 0 USB interrupt enable on transaction completion. Set/cleared by the MCU.
USBIE = 0 No interrupt
USBIE = 1 Interrupt on transaction completion
3 STALL 0 USB stall condition indication. Set/cleared by MCU.
STALL = 0 No stall
STALL = 1 USB stall condition. If set by the MCU, a STALL handshake is initiated and the bit is
cleared automatically.
4 RSV 0 Reserved = 0
5 TOGLE 0 USB toggle bit
6 NAK_INTE 0 NAK interrupt enable
NAK_INTE = 0 NAK does not trigger an interrupt.
NAK_INTE = 1 NAK triggers an interrupt.
7 UBME 0 UBM enable/disable bit. Set/cleared by the MCU.
UBME = 0 UBM cannot use this endpoint.
UBME = 1 UBM can use this endpoint.
8.9.4 OEPBCN_0: Output Endpoint-0 Buffer Byte-Count Register (XDATA at F004)
The OEPBCN_0 register contains the NAK bit and a 7-bit value used to specify the amount of data received
in a data packet from the USB host.
76543210
NAK C
6
C
5
C
4
C
3
C
2
C
1
C
0
R/W R/O R/O R/O R/O R/O R/O R/O
BIT
NAME RESET FUNCTION
6−0 C[6:0] 0000000 Byte count. Only count of 0 to 64 (00h to 40h) is supported.
00h Byte count = 0
:
40h Byte count = 64
41h to 7Fh should not be used. If the USB host sends more than 64 bytes of data to this endpoint, the
TUSB6250 hardware treats it as an illegal packet. When this condition happens, the hardware does not
update the byte count in the OEBPCN_0 register if it contains the value from the previous packet. There
is no ACK or NAK response generated by the hardware. The MCU is not informed with the arrival of this
illegal packet.
7 NAK 0 NAK = 0 Buffer is empty and ready for a host-out request.
NAK = 1 Buffer contains a valid packet from host (TUSB6250 NAKs the host-OUT request).