The emulator (and real hardware) creates ddc_specific_thread (port 1025),
duc_specific_thread (port 1026), and rx_thread[0..3] (ports 1035+) only
after receiving HP Run=1. Previously ConfigureDDCs and SendDUCSpecific
were sent before SetRunAndFreq(True), so both packets arrived at closed
ports and were silently dropped — ddcenable remained -1, rx_thread slept
forever, no IQ data ever arrived, and the 5-second timeout fired Run=0.
Fix: reorder DoConnectDevice to send Run=1 first, then DDC/DUC Specific.
Also add keepalive resend of the cached DDC Specific packet every 500 ms
for the first 5 seconds after start, to handle thread-startup races on
real hardware over the network.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
ew8bakandClaude Sonnet 4.6