From b5544e84232b80351e7c58501c1632080a354d12 Mon Sep 17 00:00:00 2001 From: user Date: Fri, 17 Jul 2026 01:28:23 +0200 Subject: net: SLIP framing over the link port + a host gateway (echo round-trip) First step of link-port networking. The LCD terminal + OSK freed the serial port from console duty, so it can be the network link. Kernel (src/net.asm): raw link-port serial that bypasses the console/ terminal - sys_ssend (transmit, GB drives the clock) and sys_srecv (receive, GB slave, blocks by yielding). Syscalls 29/30. Userland: libc ssend()/srecv(); c/necho.c does SLIP (RFC 1055) framing over them - send a packet, receive the reply, print it. Host: tools/gateway.py wraps the emulator, owns its link serial, speaks SLIP, and (for now) echoes every frame back - the "link cable adapter". Console (ASCII) bytes on the same channel are printed for visibility. Verified: `necho` sends a SLIP frame, the gateway decodes+echoes it, and gbos prints the reply - a real framed round-trip over the Game Boy link port. Next: swap the echo for actual network ops (DNS/HTTP or IRC/chat). --- c/gbos.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'c/gbos.h') diff --git a/c/gbos.h b/c/gbos.h index a0619cc..d207a75 100644 --- a/c/gbos.h +++ b/c/gbos.h @@ -13,6 +13,8 @@ char readc(void); /* one input byte, EOF at end */ void sexit(unsigned char code); unsigned char getpid(void); unsigned char pipe(void); /* -> read fd; write end is read+1 */ +void ssend(unsigned char b); /* link-port: transmit one byte */ +unsigned char srecv(void); /* link-port: receive one byte (blocks) */ /* helpers (c/libc.c) */ void putu(unsigned int n); /* print decimal */ -- cgit v1.3.1-sl0p