DK-35TS-LPC2478 Future Designs Inc, DK-35TS-LPC2478 Datasheet - Page 5

• 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
ES_LPC2478
Errata sheet
3.2 Core.1: Incorrect update of the Abort Link register in Thumb state
Introduction:
If the processor is in Thumb state and executing the code sequence STR, STMIA or
PUSH followed by a PC relative load, and the STR, STMIA or PUSH is aborted, the PC is
saved to the abort link register.
Problem:
In this situation the PC is saved to the abort link register in word resolution, instead of
half-word resolution.
Conditions:
The processor must be in Thumb state, and the following sequence must occur:
<any instruction>
<STR, STMIA, PUSH> <---- data abort on this instruction
LDR rn, [pc,#offset]
In this case the PC is saved to the link register R14_abt in only word resolution, not
half-word resolution. The effect is that the link register holds an address that could be #2
less than it should be, so any abort handler could return to one instruction earlier than
intended.
Work-around:
In a system that does not use Thumb state, there will be no problem.
In a system that uses Thumb state but does not use data aborts, or does not try to use
data aborts in a recoverable manner, there will be no problem.
Otherwise the workaround is to ensure that a STR, STMIA or PUSH cannot precede a
PC-relative load. One method for this is to add a NOP before any PC-relative load
instruction. However this is would have to be done manually.
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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