pyocd / pyocd/pyOCD

DAP_PACKET_SIZE >= 256 not fully used

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Python
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Description

Hello,

while debugging #1871 I observed, that the possible packet sizes aren't used to full extent. Probe setup was to use 2048 bytes.

  • read_ap_multi() limits its request to 64 bytes, resulting in a response with only 227 bytes
  • flashing creates requests with a maximum of 334 bytes

Regards
Hardy

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Research direction

Start by tracing read_ap_multi() and the flashing request path, then inspect how DAP_PACKET_SIZE is applied with a 2048-byte probe setup. Reproduce the reported 64-byte read limit and 334-byte flashing limit; done means available packet capacity is used without producing invalid responses.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
embedded-iot
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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