CC2510F16 Datasheet, PDF (170/244 Pages) Texas Instruments – Low-Power SoC (System-on-Chip) with MCU, Memory, 2.4 GHz RF Transceiver, and USB Controller

1. Unload the Setup Packet from the EP0
FIFO
2. Examine the contents and perform the
appropriate operations
3. Set the USBCS0.CLR_OUTPKT_RDY bit
to 1. This denotes the end of the Setup
stage. If the control transfer has no Data
stage, the USBCS0.DATA_END bit must
also be set. If there is no Data stage, the
USB Controller will stay in the IDLE
state.
12.16.5.3 IN Transactions (TX state)
If the control transfer requires data to be sent
to the host, the Setup stage will be followed by
one or more IN transactions in the Data stage.
In this case the USB controller will be in TX
state and only accept IN tokens. A successful
IN transaction comprises two or three
sequential packets (a token packet, a data
packet, and a handshake packet¹⁹). If more
than 32 bytes (maximum packet size) is to be
sent, the data must be split into a number of 32
byte packets followed by a residual packet. If
the number of bytes to send is a multiple of 32,
the residual packet will be a zero length data
packet, hence a packet size less than 32 bytes
denotes the end of the transfer.
Firmware should load the EP0 FIFO with the
first data packet and set the
USBCS0.INPKT_RDY bit as soon as possible
after the USBCS0.CLR_OUTPKT_RDY bit has
been set. The USBCS0.INPKT_RDY will be
cleared and an EP0 interrupt will be generated
when the data packet has been sent. Firmware
might then load more data packets as
necessary. An EP0 interrupt will be generated
for each packet sent. Firmware must set
USBCS0.DATA_END in addition to
USBCS0.INPKT_RDY when the last data
packet has been loaded. This will start the
Status stage of the control transfer.
EP0 will switch to the IDLE state when the
Status stage has completed. The Status stage
may fail if the USBCS0.SEND_STALL bit is set
to 1. The USBCS0.SENT_STALL bit will then
be asserted and an EP0 interrupt will be
generated as explained in Section 12.16.5.1.
If USBCS0.INPKT_RDY is not set when
receiving an IN token, the USB Controller will
reply with a NAK to indicate that the endpoint
19 _{For isochronous transfers there would not be}
a handshake packet from the host
CC2510Fx / CC2511Fx
is working, but temporarily has no data to
send.
12.16.5.4 OUT Transactions (RX state)
If the control transfer requires data to be
received from the host, the Setup stage will be
followed by one or more OUT transactions in
the Data stage. In this case the USB controller
will be in RX state and only accept OUT
tokens. A successful OUT transaction
comprises two or three sequential packets (a
token packet, a data packet, and a handshake
packet²⁰). If more than 32 bytes (maximum
packet size) is to be received, the data must
be split into a number of 32 byte packets
followed by a residual packet. If the number of
bytes to receive is a multiple of 32, the residual
packet will be a zero length data packet, hence
a data packet with payload less than 32 bytes
denotes the end of the transfer.
The USBCS0.OUTPKT_RDY bit will be set and
an EP0 interrupt will be generated when a data
packet has been received. The firmware
should set USBCS0.CLR_OUTPKT_RDY when
the data packet has been unloaded from the
EP0 FIFO. When the last data packet has
been received (packet size less than 32 bytes)
firmware should also set the
USBCS0.DATA_END bit. This will start the
Status stage of the control transfer. The size of
the data packet is kept in the USBCNT0
registers. Note that this value is only valid
when USBCS0.OUTPKT_RDY=1.
EP0 will switch to the IDLE state when the
Status stage has completed. The Status stage
may fail if the DATA1 packet received is not a
zero length data packet or if the
USBCS0.SEND_STALL bit is set to 1. The
USBCS0.SENT_STALL bit will then be
asserted and an EP0 interrupt will be
generated as explained in Section 12.16.5.1.
12.16.6 Endpoints 1 - 5
Each endpoint can be used as an IN only, an
OUT only, or IN/OUT. For an IN/OUT endpoint
there are basically two endpoints, an IN
endpoint and an OUT endpoint associated with
the endpoint number. Configuration and
control of IN endpoints is performed through
the USBCSIL and USBCSIH registers. The
USBCSOL and USBCSOH registers are used to
20 _{For isochronous transfers there would not be}
a handshake packet from the CC2511Fx
SWRS055F
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