ISP1181ABS NXP Semiconductors, ISP1181ABS Datasheet - Page 20

• Manufacturer Part Number: ISP1181ABS
• Manufacturer: NXP Semiconductors

Specifications of ISP1181ABS

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Compliant

Philips Semiconductors
9397 750 13959
Product data
10.4.2 Isochronous endpoints
Short packet:
before any DMA transfer takes place. When a short packet has been enabled as EOT
indicator (SHORTP = 1), the transfer size is determined by the presence of a short
packet in the data. This mechanism permits the use of a fully autonomous data
transfer protocol.
When reading from an OUT endpoint, reception of a short packet at an OUT token
will stop the DMA operation after transferring the data bytes of this packet.
Table 10:
[1]
A DMA transfer to/from an isochronous endpoint can be terminated by any of the
following conditions (bit names refer to the DMA Configuration Register, see
Table
Table 11:
EOT condition
EOT input
DMA Counter Register
Short packet
DMAEN bit in DMA
Configuration Register
EOT condition
EOT input active
DMA Counter Register zero
End-Of-Packet
•
•
•
•
An external End-Of-Transfer signal occurs on input EOT
The DMA transfer completes as programmed in the DMA Counter register
(CNTREN = 1)
An End-Of-Packet (EOP) signal is detected
DMA operation is disabled by clearing bit DMAEN.
The DMA transfer stops. However, no interrupt is generated.
24):
Summary of EOT conditions for a bulk endpoint
Recommended EOT usage for isochronous endpoints
Normally, the transfer byte count must be set via a control endpoint
Rev. 05 — 08 December 2004
OUT endpoint
EOT is active
transfer completes as
programmed in the DMA
Counter register
short packet is received and
transferred
DMAEN = 0
OUT endpoint
do not use
do not use
preferred
[1]
Full-speed USB peripheral controller
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
IN endpoint
EOT is active
transfer completes as
programmed in the DMA
Counter register
counter reaches zero in the
middle of the buffer
DMAEN = 0
IN endpoint
preferred
preferred
do not use
ISP1181A
[1]
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