DK-35TS-LPC2478 Future Designs Inc, DK-35TS-LPC2478 Datasheet - Page 4

• Manufacturer Part Number: DK-35TS-LPC2478
• Description: PROGRAMMERS, DEVELOPMENT SYSTEMS
• Manufacturer: Future Designs Inc

Specifications of DK-35TS-LPC2478

• Sensor Type: Touch Screen
• Interface: I²C
• Voltage - Supply: 5V
• Embedded: Yes, MCU, 16/32-Bit
• Utilized Ic / Part: LPC2478 ARM7
• For Use With: 568-4742 - MODULE DIMM LPC2478 ARM7
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sensitivity: -
• Sensing Range: -
• Other names: 622-1034; ARM-35TS-LPC2478

NXP Semiconductors
3. Functional problems detail
ES_LPC2478
Errata sheet
3.1 Ethernet.1: Ethernet TxConsumeIndex register does not update
correctly after the first frame is sent
Introduction:
The transmit consume index register defines the descriptor that is going to be transmitted
next by the hardware transmit process. After a frame has been transmitted hardware
increments the index, wrapping the value to 0 once the value of TxDescriptorNumber has
been reached. If the TxConsumeIndex equals TxProduceIndex the descriptor array is
empty and the transmit channel will stop transmitting until software produces new
descriptors.
Problem:
The TxConsumeIndex register is not updated correctly (from 0 to 1) after the first frame is
sent. After the next frame sent, the TxConsumeIndex register is updated by two (from 0 to
2). This only happens the very first time, so subsequent updates are correct (even those
from 0 to 1, after wrapping the value to 0 once the value of TxDescriptorNumber has been
reached)
Work-around:
Software can correct this situation in many ways; for example, sending a dummy frame
after initialization.
All information provided in this document is subject to legal disclaimers.
Rev. 6 — 1 March 2011
ES_LPC2478
Errata sheet LPC2478
© NXP B.V. 2011. All rights reserved.
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