Roflin
9c4bc7a61c
Second W5100S-vs-W5100 gotcha found at bring-up: the W5100S has a Network Lock Register (NETLCKR, 0x0071) the original W5100 lacks. It defaults to 0x00 (locked), and while locked, ALL writes to GWR/SUBR/SHAR/SIPR are silently dropped -- so the chip has no source IP/MAC and the UDP/MACRAW send builds nothing (chip reports SEND_OK but transmits nothing; socket registers aren't locked, which is why an indirect write/readback of Sn_PORT succeeded). Fix: write the unlock value 0x3A to NETLCKR right after MR enables indirect mode, before the network-config writes. On the bench this flipped the board from silent to actually keying frames onto the wire (magjack activity LED now blinks). Also: - bba_top.py test model: RX buffer base 0x6000 -> 0xC000 to match the W5100S buffer-base fix (the model hardcoded the old W5100 address). - w5100_selftest.py: added an indirect-mode (IDM) write/readback probe of a socket register + IND= field in the UART report, to isolate direct-vs-indirect access (confirmed indirect works on the real chip). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>