From ba2d7ae1d7b319645b10aaa31a7f664f9f80c25c Mon Sep 17 00:00:00 2001 From: user Date: Sat, 18 Jul 2026 00:38:38 +0200 Subject: refactor: c/ -> usr/, compiled program blobs out of the source tree Userland sources live in usr/ (fits the Unix theme better than 'c'). SDCC output .bin blobs land in build/usr/ with the other build artifacts instead of littering the source dir; programs.asm INCBINs them from there. Byte-identical ROM. --- usr/netlib.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 usr/netlib.h (limited to 'usr/netlib.h') diff --git a/usr/netlib.h b/usr/netlib.h new file mode 100644 index 0000000..ec98eac --- /dev/null +++ b/usr/netlib.h @@ -0,0 +1,39 @@ +#ifndef NETLIB_H +#define NETLIB_H +/* SLIP (RFC 1055) framing over the link port. Header-only so each program gets + its own copy (the C build links one translation unit per program). */ +#include "gbos.h" + +#define SLIP_END 0xC0 +#define SLIP_ESC 0xDB +#define SLIP_ESC_END 0xDC +#define SLIP_ESC_ESC 0xDD + +/* send a framed packet (len up to 255) */ +static void slip_send(const char *buf, unsigned char len) { + unsigned char i, c; + ssend(SLIP_END); + for (i = 0; i < len; i++) { + c = (unsigned char)buf[i]; + if (c == SLIP_END) { ssend(SLIP_ESC); ssend(SLIP_ESC_END); } + else if (c == SLIP_ESC) { ssend(SLIP_ESC); ssend(SLIP_ESC_ESC); } + else ssend(c); + } + ssend(SLIP_END); +} + +/* receive one framed packet into buf (max), returns its length */ +static unsigned char slip_recv(char *buf, unsigned char max) { + unsigned char len = 0, c; + for (;;) { + c = srecv(); + if (c == SLIP_END) { if (len) return len; continue; } + if (c == SLIP_ESC) { + c = srecv(); + if (c == SLIP_ESC_END) c = SLIP_END; + else if (c == SLIP_ESC_ESC) c = SLIP_ESC; + } + if (len < max) buf[len++] = (char)c; + } +} +#endif -- cgit v1.3.1-sl0p