MC68HC908BD48 Datasheet, PDF (171/290 Pages) Freescale Semiconductor, Inc – Microcontrollers

Universal Serial Bus Module (USB)
Registers
13.5.4 USB Control Register 0 (UCR0)
Address: $002B
Bit 7
6
5
4
3
2
1
Bit 0
Read:
T0SEQ STALL0
Write:
TX0E
RX0E TP0SIZ3 TP0SIZ2 TP0SIZ1 TP0SIZ0
Reset: 0
0
0
0
0
0
0
0
Figure 13-4. USB Control Register 0 (UCR0)
T0SEQ — Endpoint 0 Data Packet PID Select
This bit will determine the transmit data packet PID of endpoint 0.
When it is "0", the DATA0 PID (b0011) will be sent. When it is "1", the
DATA1 PID (b1011) will be sent. Reset clears this bit.
1 = DATA1 PID will be sent on endpoint 0
0 = DATA0 PID will be sent on endpoint 0
STALL0 — Endpoint 0 STALL Handshake
This bit is set to generate the STALL handshake packet as next IN or
OUT transactions handshake packet from endpoint 0. The USB
hardware clears the STALL0 bit when a SETUP packet is received.
Reset clears this bit.
1 = Send STALL handshake on endpoint 0
0 = Do not send STALL handshake on endpoint 0
TX0E — Endpoint 0 Transmit Enable
This bit is set to enable data packet transmission from endpoint 0.
Software should set this bit when data is ready for data packet
transmission. It must be cleared when no more data needs to be
transmitted. If TX0E is "0" or TXD0F is "1", a NAK handshake will be
returned for the next IN token. Reset clears this bit.
1 = Data is ready to be sent on endpoint 0
0 = Data is not ready; respond with ACK
MC68HC908BD48 — Rev. 1.0
MOTOROLA
Universal Serial Bus Module (USB)
Technical Data
171