Roflin
c16afb6eea
An interactive UART command shell drives a UDP send/receive test on the W5100's socket 3, running ALONGSIDE the live BBA (socket-0 MACRAW) with EXI keeping bus priority. MACRAW+UDP coexistence is W5100S-datasheet confirmed (S4.6 + "4 independent SOCKETs"). Now the default flash build (--console selects the old event-log console). New / changed gateware: - uart_shell.py (new): rebbarb> shell over FT2232H channel B. Commands: help; udp unicast <ip> [msg]; udp broadcast [msg]. After each send it waits (bounded, else "timeout") for a reply and prints "rx <payload>". Line buffer + message ROM live in block RAM with a sequential parser (LC-efficient); 1-deep RX holding reg keeps pastes intact. 8 sim tests. - w5100_parallel_master.py: configurable UDP socket (default 3) with UDP send AND receive (IP-stack init, runtime dest IP, WIZnet UDP RX header + payload). Gated by enable_udp_test so the MACRAW path is unchanged when off. Tests U1-U4 + MACRAW T1-T5. - exi_capture.py: CAPTURE-DOMAIN CRITICAL-PATH FIX. The TX byte-FIFO read-enable was gated by its own gray-coded ready (r_en = ... | (flushing & r_rdy)), forming a consume_ptr -> gray -> r_rdy -> flush -> r_en -> consume_ptr loop that capped capture_clk. Replaced the r_rdy-based "drain until empty" flush with a fixed-length drain counter (FIFO is only tx_depth deep), removing the pointer feedback from r_en. Path 24.3 -> 19.6 ns; flush behavior preserved. - bba_top.py: wire shell <-> W5100 UDP (send + rx); shell additive. - synth.py: shell default build; env-var UDP network config; documents a reverted PNR-timing-priority experiment. Timing (--seeds 8, default shell build, 67% LC): capture closes on 4/8 seeds (best seed 4 = 58.36 MHz, +8%), clk passes on all. This is BETTER than the pre-shell 2/8 baseline because the flush fix improved the capture domain intrinsically. Flash build/seed4/top.bin. Bring-up caveats (unchanged): W5100 socket register addresses / UDP header format are datasheet-derived (confirm on hardware); UDP_SRC_IP / subnet / gateway must match the LAN for unicast ARP. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>