I am testing the following setup:
MCU (Nordic nRF52840) → UART (via level shifter) → Module → TCP server
During testing, I observed different UART throughput depending on whether Local Echo is enabled in Tera Term.
Test results:
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Local Echo disabled
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UART throughput from the Nordic nRF52840 is very low, typically around 2–3 KB/s, and occasionally drops to around 20 B/s.
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Local Echo enabled
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UART throughput increases significantly to approximately 11 KB/s.
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This behavior is unexpected because the Local Echo setting in Tera Term should only affect what is displayed locally on the PC and should not influence the actual UART transmission rate.
Has anyone encountered similar behavior or can explain why enabling Local Echo would have such a significant impact on UART throughput? Any suggestions on what to investigate would be appreciated.
Thank you.