isp1161bm NXP Semiconductors, isp1161bm Datasheet - Page 103

• Manufacturer Part Number: isp1161bm
• Description: Isp1161 Full-speed Universal Serial Bus Single-chip Host And Device Controller
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 09567
Product data
13.2.3 Stall Endpoint/Unstall Endpoint (40H–4FH/80H—8FH)
13.2.4 Validate Endpoint Buffer (R/W: 6FH/61H)
Table 94:
These commands are used to stall or unstall an endpoint. The commands modify the
content of the DcEndpointStatus register (see
A stalled control endpoint is automatically unstalled when it receives a SETUP token,
regardless of the packet content. If the endpoint should stay in its stalled state, the
microprocessor can re-stall it with the Stall Endpoint command.
When a stalled endpoint is unstalled (either by the Unstall Endpoint command or by
receiving a SETUP token), it is also re-initialized. This flushes the buffer: if it is an
OUT buffer it waits for a DATA 0 PID, if it is an IN buffer it writes a DATA 0 PID.
Code (Hex): 40 to 4F — stall (control OUT, control IN, endpoint 1 to 14)
Code (Hex): 80 to 8F — unstall (control OUT, control IN, endpoint 1 to 14)
Transaction — none
This command signals the presence of valid data for transmission to the USB host, by
setting the Buffer Full flag of the selected IN endpoint. This indicates that the data in
the buffer is valid and can be sent to the host, when the next IN token is received. For
a double-buffered endpoint this command switches the current FIFO for CPU access.
Remark: For special aspects of the control IN endpoint see
Code (Hex): 61 to 6F — validate endpoint buffer (control IN, endpoint 1 to 14)
Transaction — none
Bit
7
6
5
4
3
2
1
0
DcEndpointStatus register: bit description
Symbol
EPSTAL
EPFULL1
EPFULL0
DATA_PID
OVERWRITE
SETUPT
CPUBUF
-
Rev. 02 — 13 December 2002
Description
This bit indicates whether the endpoint is stalled or not
(1 = stalled, 0 = not stalled).
Set to logic 1 by a Stall Endpoint command and cleared to
logic 0 by an Unstall Endpoint command. The endpoint is
automatically unstalled upon reception of a SETUP token.
Logic 1 indicates that the secondary endpoint buffer is full.
Logic 1 indicates that the primary endpoint buffer is full.
This bit indicates the data PID of the next packet (0 = DATA PID,
1 = DATA1 PID).
This bit is set by hardware, logic 1 indicating that a new SETUP
packet has overwritten the previous set-up information, before it
was acknowledged or before the endpoint was stalled. This bit is
cleared by reading, if writing the set-up data has finished.
Firmware must check this bit before sending an Acknowledge
SETUP command or stalling the endpoint. Upon reading logic 1
the firmware must stop ongoing set-up actions and wait for a
new SETUP packet.
Logic 1 indicates that the buffer contains a SETUP packet.
This bit indicates which buffer is currently selected for CPU
access (0 = primary buffer, 1 = secondary buffer).
reserved
Full-speed USB single-chip host and device controller
Table
93).
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
Section
ISP1161
11.3.6.
103 of 137