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* term: dark mode - black background, white text (OSK highlight inverts to match)user4 days2-12/+17
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* irc: a bitchx/irssi-style IRC clientuser4 days1-0/+7
| | | | | | | | | | | | | | | | | | | | | | | irc HOST [NICK] - connects over the kernel TCP stack (DNS-resolves the host), registers, and runs a live client on the 40x18 LCD. UI, within the terminal's means (no cursor addressing - just \r + \b): messages scroll above a fixed irssi-style input line '[#chan] text_' redrawn in place; long input scrolls horizontally. The elders' formats: <nick> msg, <nick:#c> off-channel, *nick* private, -nick- notice, * nick action, >target< outbound, -!- server/status. Keys come from both the OSK (SELECT) and the console ring (pollcon), so a hub can drive it. Commands: /join /part /msg /me /nick /quit /raw, plus bare text to the current channel. Handles PING (PONG + a wink), CTCP ACTION/VERSION, JOIN/PART/QUIT/KICK/NICK, 332/353 topic+names, and 433 nick-in-use (auto-appends _). Registers on bank 32 as program id 30. Note: gbos doesn't zero C statics, so main() inits its state explicitly; the local TCP port is randomized (DIV) to dodge a stale server-side half-open from an unclean prior exit. Tested end to end against a small ircd through gbhub: full MOTD burst, join, channel + private messages, actions, and bot replies all render correctly.
* net: SYS_POLLCON + larger console ring for link-injected inputuser4 days3-3/+19
| | | | | | | | | | | | | | | Programs that own their main loop (the IRC client) need to poll for typed input without blocking. pollin() only sees the on-screen keyboard; bytes injected over the link (gbhub 'type', for scripted/hub-driven sessions) land in the kernel console ring, previously only drained by the blocking KGetc path. Add SYS_POLLCON: a non-blocking con_pop for userland. Also enlarge that console ring 16 -> 64. One net_pump drains an entire serial burst into the ring at once, so a whole injected command line has to fit or bytes are dropped and lines merge (a 20-char command came out truncated and glued to the next). 64 covers a full line; mask stays a power of two.
* net: fix truncated TCP field offsets corrupting multi-segment recvuser4 days1-4/+10
| | | | | | | | | | | | | | | | | | | | | SK_STATE/SK_SND/SK_RCV sat at struct offsets 305/306/310, past the 288-byte SK_RXBUF. But the field accessors add the offset as an 8-bit immediate (add SK_x; ld l,a), so rgbasm truncated 305->49, 306->50, 310->54 (the -Wtruncation warnings we'd been ignoring) - putting STATE and the sequence numbers *inside* RXBUF at offsets 49/50/54. Any TCP segment with >=33 payload bytes therefore overwrote the connection's own STATE and rcv_nxt/snd_nxt with message text. The first segment of a stream landed, its data clobbered STATE to a garbage value, and every subsequent segment was dropped because tcp_in no longer saw ESTABLISHED - so multi-segment TCP receives (an IRC MOTD, any HTTP body past one segment) silently stalled. wget appeared to 'work' only because a single-segment reply plus a never-honored FIN still printed once. Fix: reorder the struct so STATE/SND/RCV precede the big RXBUF, keeping every field offset < 256 (SK_SIZE unchanged at 314, all accessors are symbolic). Zero -Wtruncation warnings remain. Verified an 11-line IRC registration burst now arrives intact.
* net: unbreak ping against hosts that intermittently drop ICMPuser4 days1-3/+54
| | | | | | | | | | | | | | | | | | | | | | | | | Pinging sl0p.foo through gbhub looked hung: DNS resolved, then nothing. Packet-tracing showed the echo request leaving the hub's TUN and eth0 correctly NATed every time - but 80.78.19.56 blackholes ICMP for all ids in windows of tens of seconds (provider rate limiting). One lost reply wedged ping for minutes because net_recv's pump-counted timeout is effectively unbounded at native emulation speed. Two fixes: - NET_RECVNB (op 8): non-blocking recv - one RX pump, $FE if nothing buffered, same delivery/EOF semantics as NET_RECV otherwise. ping now waits <=~2s per seq (net_recv_nb + msleep loop), prints 'seq=N timeout' and moves on, like real ping. - ICMP echo id was hardcoded $1234 for every GB, every boot, so all sessions produced byte-identical flows - hostile to NAT conntrack (keyed on icmp id). wNetEchoId is now our host octet + rDIV timing noise sampled at DHCP lease, distinct per GB and per boot. Verified: 8 back-to-back native-speed gbhub runs, zero hangs; a run that hit a blackhole window printed seq=1 timeout then recovered to 3/4 received. GB<->GB ping and DNS/DHCP unaffected.
* net: pump the network from the console wait (answer pings at the prompt)user4 days3-42/+85
| | | | | | | | | | | | | | | A Game Boy sitting at the shell prompt now services the network instead of being deaf until you run netd: KGetc (the console input wait) pumps net_pump each poll, so inbound pings are auto-answered while idle. net_pump gained an in-frame model and routes any non-framed link bytes to a small console-input ring (con_push/con_pop), so a headless-injected command still reaches the shell while SLIP frames go to the stack. Removes the old SLIP-skip-in-KGetc hack. Verified: two Game Boys on the hub, GB0 idle at the prompt (no netd), GB1 `ping 10.0.0.2` -> 4/4 replies, routed GB1->hub->GB0->hub->GB1. (Separate, pre-existing: gbhub *spawn* mode and windowed gbjoin can drop an idle link socket - under investigation; daemon mode + headless is solid.)
* net: DHCP client - lease the IP at boot instead of hardcoding ituser4 days2-29/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The address is no longer baked in. net_init starts at 0.0.0.0; a DHCP client runs as the first thing on boot (init/shell forks it and waits), and only once it has a lease (or gives up) does the prompt appear. Kernel: - IP is configurable: 0.0.0.0 until leased; NET_SETIP op stores it. - 16-bit frame length. DHCP/BOOTP packets are ~272 bytes, over the old 255-byte frame cap, so net_slip_send takes a 16-bit length, net_pump assembles into a 320-byte buffer with a 16-bit wNetRxLen, and udp_send writes a 16-bit IP total. Payloads stay <=255 (kept small on purpose) so the per-protocol datalen math is unchanged. wNetTx/wNetRxBuf 256->320, SK_RXBUF 208->288. Userland: - c/dhcp.c: DISCOVER->OFFER->REQUEST->ACK over a UDP socket, then net_setip(); times out gracefully (shell still boots) if there's no server. sh.c runs it before the prompt. Bridge (self-contained DHCP server, no dnsmasq): - tunbridge.py + netboot intercept UDP->:67 and answer OFFER/ACK leasing 10.0.0.2 (gateway 10.0.0.1); everything else is bridged/NATed as before. Regression-tested ICMP/UDP/TCP after the 16-bit change. Verified end to end: dhcp: discovering dhcp: leased 10.0.0.2 /# ping 10.0.0.1 -> 4/4 (traffic from the leased address)
* kernel: sys_sleep - a cooperative delay off the DIV timer (+ ping pacing)user4 days2-0/+44
| | | | | | | | | | | | | | There was no time source at all (IRQ vectors just reti; scheduler is purely cooperative). The DIV register (FF04) free-runs at 16384 Hz regardless of interrupts, so sys_sleep accumulates DIV deltas across SchedYields (other procs keep running) until the requested number of 1/64-second units elapse. - SYS_SLEEP(34): B = 1/64s units; libc gsleep(units) / msleep(ms) wrappers. - ping now msleep(800) between echoes, so it paces like real ping instead of blasting all four at once. Verified real-time (capped emulator): replies land ~0.85s apart. In --uncapped runs the delay is GB-time (fast wall-clock), as expected.
* net: keep network packets out of the console (fixes shell garbage on netboot)user4 days2-0/+24
| | | | | | | | | | | | | | | | | The link port is both the console-input fallback and the network. At the shell prompt the host's multicast (mDNS/LLMNR/IGMP) was fed to the serial and KGetc read those packet bytes as console input -> garbage in the shell, OSK unusable. Two-part fix: - KGetc now skips SLIP frames (0xC0-delimited) on the serial console path, so inbound packets never surface as console input. Plain injected bytes (the headless tunbridge command path) still pass through. New wConInSkip flag. - netboot/tunbridge only forward IP packets destined to 10.0.0.2 (drop the multicast noise at the bridge). Verified: GB sits at a clean "/#" prompt while all packets (noise included) are forwarded; being-pinged (3/3) and wget still work. On the emulator, the OSK is SELECT=space, START=enter, A=z, B=x, d-pad=WASD/arrows.
* net: TCP sockets in the kernel - a Game Boy fetches HTTP over real TCPuser5 days1-8/+678
| | | | | | | | | | | | | | | | | | | | | | | | | Kernel TCP client on the socket layer: net_connect(SOCK_TCP) runs the 3-way handshake in-kernel, send()/recv() drive the byte stream, close() does the FIN. - Socket gains state + 32-bit snd_nxt/rcv_nxt (big-endian, add-with-carry-fold). - tcp_send_seg builds IP+TCP with a pseudo-header checksum; the SYN carries an MSS option (200) so the peer never sends a segment larger than our 256-byte frame buffer (we don't do IP reassembly). - tcp_in state machine: SYN_SENT->ESTABLISHED on SYN-ACK, buffers in-order data and ACKs it, handles FIN -> recv() returns 0 (EOF). - No retransmission: the GB<->host link is lossless and the host's real TCP owns the internet side - which removes TCP's hardest part. - net_pump now processes one frame per call so recv drains each segment before the next arrives (single rx slot, no overwrite). wget.c is now a thin socket client: connect -> send "GET / HTTP/1.0" -> recv to EOF -> print. Verified end to end against a host HTTP server: /# wget 10.0.0.1 HTTP/1.0 200 OK Hello from a real HTTP server, fetched by a Game Boy! with a clean SYN/SYN-ACK/ACK ... PSH ... FIN/ACK trace on the wire.
* net: UDP sockets in the kernel + a DNS resolver (real hostname lookups)user5 days2-21/+328
| | | | | | | | | | | | | | | | | | | | Adds UDP to the kernel socket layer on top of the ICMP core: - net_sum() (raw folded sum) split out of net_cksum() so a UDP pseudo-header (src/dst IP + proto + length) can seed the segment checksum. - udp_send: builds IP+UDP with the pseudo-header checksum; NET_BIND sets the local/source port; net_connect sets the peer. - udp_in: demuxes inbound UDP by destination port to the bound socket (net_find_udp), delivers the payload + source addr. Also fixes a real recv bug: net_pump clobbers BC/DE/HL, so the old recv timeout counted in registers and was effectively random. recv now counts in WRAM. New `nslookup HOST` (PROG_NSLOOKUP=28, bank 30): builds a DNS A query and parses the answer (with 0xC0 name-compression) entirely in userland over a UDP socket - the kernel never sees DNS, just UDP. Verified through the bridge NAT: /# nslookup example.com -> example.com -> 172.66.147.243 This gives us name resolution for the TCP/HTTP demo next.
* net: proper socket API in the kernel (SYS_NET) - no more SLIP in userlanduser5 days3-0/+756
| | | | | | | | | | | | | | | | | | | | | | | | The network stack moves into the kernel. src/socket.asm owns SLIP framing, IPv4, RFC1071 checksums, and ICMP; programs now speak a socket API through one syscall (SYS_NET, DE=&netreq dispatched by op): net_socket/connect/send/recv/ close/poll (c/sock.h). No program touches SLIP, IP headers, or checksums. - Socket table (4 sockets) + tx/rx buffers in WRAM0; our IP = 10.0.0.2. - net_pump: drains the link, reassembles SLIP frames, demuxes IPv4. Inbound ICMP echo requests are auto-answered in-kernel, so the GB replies to pings whenever any process pumps RX. - ICMP sockets: send() emits an echo request to the connected peer; recv() returns the matching reply (with a spin/yield timeout). ping.c is now a ~15-line socket client; netd.c is just `for(;;){net_poll(); yield();}`. Verified over tunbridge: /# ping 1.1.1.1 -> replies from the real internet (kernel builds it all) host# ping 10.0.0.2 -> 4/4, 0% loss (kernel auto-answers) Gotchas recorded: gbos.inc isn't a make dep (touch asm after editing); this crt0 doesn't copy initializers (fill arrays at runtime); and the arg string at 0xA000 overlaps _DATA, so parse targets must sit past it (big buffer first). UDP and TCP sockets build on this same core next.
* net: ping - GB-originated ICMP echo (a Game Boy pings the real internet)user5 days1-0/+7
| | | | | | | | | | | | | | | New `ping [A.B.C.D]` program (PROG_PING=27, bank 29): builds and sends ICMP echo requests from 10.0.0.2, then reads replies off the link port. It keeps reading SLIP frames until it finds *our* echo reply, skipping the IGMP/mDNS/ SSDP multicast noise that shares 10.0.0.0/24. Reply wait uses a generous srecv_nb spin budget since the emulator runs uncapped (no timer syscall yet). Verified over the tunbridge (with NAT): /# ping 10.0.0.1 -> 4/4 received, ttl=64 (the SLIP peer/host) /# ping 1.1.1.1 -> 4/4 received, ttl=56 (Cloudflare, real net!) ttl=56 is a real internet round trip (64 minus the hops). Combined with the host being able to ping the GB, the Game Boy is now a full two-way ICMP host.
* net: real IP stack, milestone A - ICMP echo (you can ping a Game Boy)user5 days1-0/+7
| | | | | | | | | | | | | | Start of an actual TCP/IP stack on gbos (TLS stays in a proxy). netd is a userland IP responder over SLIP: our address is 10.0.0.2, the SLIP peer 10.0.0.1. It parses IPv4 headers, answers ICMP echo requests, and rebuilds the packet with correct IP + ICMP checksums (RFC 1071 one's-complement sum, carry-folded - works fine on the SM83). c/netd.c + register; tools/gateway.py gains --mode ping: it crafts ICMP echo requests over SLIP and verifies the replies. Verified: `netd` answers 4 pings, gateway reports reply from 10.0.0.2 with cksum=ok for each. Next: UDP, then TCP.
* net: chat client - async receive + OSK send over the link portuser5 days3-0/+31
| | | | | | | | | | | | | | | | | | | | | | | The application layer of the link-port demo, and it ties the whole system together: the LCD terminal displays, the on-screen keyboard types, and the link port carries a live chat. Kernel: sys_srecv_nb (non-blocking link receive; A=byte, CF=none) and sys_pollin (poll the OSK for a typed char without blocking) - syscalls 31/32. Both are what a poll loop needs to receive and type at once. Userland: c/chat.c runs a poll loop - it feeds non-blocking bytes through a SLIP receive state machine and prints whole incoming frames as messages, while pollin() drives the on-screen keyboard; SELECT shows the keys, type a line, START sends it as a frame. libc srecv_nb()/pollin(). Host: tools/gateway.py --mode chat is a simple bot peer (echoes each GB message and injects a few async ones); --keys can drive the OSK for tests. Verified: the gateway pushes 'welcome', '<alice> hey gameboy!', '<bob> nice link cable' unprompted and the GB displays all three (async receive); typing 'hi' on the OSK echoes it and emits the SLIP frame \xC0hi\xC0 (send). A Game Boy in the chat, keyboard on screen, over the link cable.
* net: wget - real HTTP over the link port via the gatewayuser5 days1-0/+7
| | | | | | | | | | | | | | | | Grow the link-port demo from echo to actual network access. The Game Boy still only does SLIP framing + display; the host gateway does DNS/TCP/HTTP. - c/netlib.h: SLIP framing factored out (header-only, per-program copy). necho.c now uses it too. - c/wget.c: `wget URL` frames the URL, then prints the reply body. The gateway streams the body back as typed frames: 'D'<chunk> ... 'E'. - tools/gateway.py: add --mode http (urlopen the frame as a URL, cap the body, chunk it) alongside --mode echo; --cmd runs any gbos command. Verified: `wget example.com` streams back the full Example Domain HTML onto the terminal; `wget sl0p.foo` fetches the real page. A Game Boy on the web, over the link cable.
* net: SLIP framing over the link port + a host gateway (echo round-trip)user5 days3-0/+50
| | | | | | | | | | | | | | | | | | | | 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).
* pipe: PIPE_MAX 2->4 (5-stage pipelines) + fix cross-yield byte corruptionuser5 days1-9/+22
| | | | | | | | | | | | | | | | | | | Bump PIPE_MAX to 4 so a|b|c|d|e (4 pipes) works. This stays within the single-byte buffer-offset math (idx*64+pos <= 3*64+63 = 255) and the fd space ($F0..$F7, clear of $FF console). The bump exposed a data-corruption bug that also affected the 2-pipe case (just invisibly - a wc-only test can't see mangled bytes): pipe_write kept the byte-to-write in the SHARED wPipeByte global across its SchedYield (buffer full), so a concurrent pipe op clobbered it and the writer then stored the wrong byte. Now the byte is held in D across the yield, and pipe_bufptr no longer clobbers D; pipe_read/pipe_write also push their idx across SchedYield rather than assume the yield preserves registers. Verified: count N | cat now streams EXACT content (no 'linn'/'llne' corruption); count 60 | cat | cat | wc = 60 180 1671; 5-stage count 4 | cat | cat | cat | cat prints line 1..4; SIGPIPE (count 200|true) and count 100|wc still fine, no hangs.
* kernel+sh: real anonymous pipes (concurrent, streaming, SIGPIPE)user5 days5-1/+256
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the shell's temp-file pipe hack with proper in-kernel FIFOs. Kernel (src/pipe.asm, new): - A small pool of bounded ring buffers (PIPE_MAX=2, 64 B each) with writers/readers refcounts. Pipe fds are $F0+idx*2 (read) / +1 (write); $FF stays "console". - SYS_PIPE allocates one (writers=readers=1) and returns the read fd (write = read+1). getb/putb/close dispatch pipe fds here; sys_exit drops the refcounts held as PROC_STDIN/PROC_STDOUT. - Blocking with SchedYield, which is the flow control: read blocks while empty with a writer (EOF once writers hit 0), write blocks while full with a reader, and if the last reader is gone the writer is killed (SIGPIPE -> exit 141). Cooperative-scheduler friendly. Shell (c/sh.c): - run_pipeline(): split on '|', make a pipe between adjacent stages, and fork ALL stages concurrently (no wait between), wiring stdin/stdout; then wait for all. Per-stage >/< still honored; orphaned pipe ends are closed on a lookup miss so EOF/EPIPE propagate. - Drop the __pipe temp file and its 2 KB / serialized limits. libc: pipe(). New c/ptest.c exercises the FIFO (write, read back, EOF). Now works (old version couldn't): multi-stage a|b|c; streaming beyond 2 KB (count 120 | wc = 3372 bytes through a 64 B buffer); early-exit SIGPIPE (count 200 | true kills count instead of hanging/overflowing a file).
* term: compute the OSK view offset from the cursor row (keep input visible)user5 days2-17/+33
| | | | | | | | | | | | | | | | | A fixed offset of OSK_ROWS pushed the cursor off the top of the screen when there was little backlog (e.g. a fresh terminal: cursor at logical row 0 -> screen row -3, hidden). Now the offset is max(0, wCurRow - 14): 0 when the cursor is within the visible area, growing only enough to keep the cursor line at the bottom visible row (14) once the terminal has filled past it. compute_offset (from wOskVisible + wCurRow) runs at the top of term_write_tilemap; cursor_down re-runs the tilemap when the cursor changes rows while the OSK is up; osk_toggle just re-runs it. Shared OSK_DOCK constant in gbos.inc keeps term.asm and osk.asm in sync. Verified: fresh terminal + OSK shows the input at row 0; filling past row 14 shifts the view to hold the input at row 14; full screen + OSK puts it at row 14; toggle on+off is still lossless.
* term/osk: view-offset scroll region (lossless backlog on OSK toggle)user5 days2-62/+35
| | | | | | | | | | | | | | Replace the shrink-and-scroll region with a view offset. The terminal is always 18 logical rows; term_write_tilemap maps screen row -> logical row + wViewTop (rows the OSK covers clamp to the cursor line). Showing the OSK sets the offset to OSK_ROWS so the cursor line lands at row 14 (above the keyboard) and hiding it sets the offset back to 0 - now purely a remap, so nothing is scrolled off or destroyed. term_set_view replaces term_set_rows; term_scroll/cursor_down are back to plain 18-row scrolling. Result: full 18-row backlog when the OSK is hidden, a shifted 15-row window when shown, and toggling is lossless (verified: OSK-shown view == baseline rows 3..17, and toggle on+off == baseline exactly).
* term/osk: scroll region so the OSK never hides the input lineuser5 days3-12/+69
| | | | | | | | | | | | | | | | | | | The terminal now has a variable usable height (wTermRows). term_scroll and cursor_down operate within [0 .. wTermRows-1], and term_set_rows(n) shrinks or grows that region, scrolling the cursor up into view when it would fall outside. osk_toggle shrinks the terminal to the rows above the keyboard on show (18 - OSK_ROWS = 15) and restores full height on hide, so the active line is always visible just above the docked keyboard, and hiding the OSK reclaims all 18 rows. Also add c/count.c ("count [n]", default 25): prints n numbered lines to observe/debug scrolling and the scroll-region behavior. Registered as program id 21 / bank 23. Fixed the arg to read argv[0] (getargs returns the string after the command name). Verified: filling the screen then opening the OSK scrolls the latest line to row 14 (visible) with the keyboard at 15-17; closing it restores rows 15-17; count N prints exactly N lines.
* osk: bind START to Enter (CR)user5 days1-0/+7
| | | | | START now returns $0A regardless of cursor position, so you can submit a command without navigating to the CR key. The CR key still works too.
* sh: handle backspace in readline; prompt is now '#'user5 days1-1/+14
| | | | | | | | | | | | readc() returning $08/$7F now drops the last char from the command buffer (and emits one $08 so the terminal erases it) instead of storing the raw byte. Previously "lz<bksp>s" left the buffer as "lz\x08s", so the command "ls" was reported "not found" even though the screen showed "ls". Also change the shell prompt from '$' to '#'. osk: B button types the selected key SHIFTED (uppercase a-z). A types the key as shown (lowercase/digit/symbol); B on a letter subtracts 32 for the uppercase glyph (the font already has A-Z). Non-letters are unchanged.
* osk: wrap the cursor around all four edgesuser5 days1-19/+27
| | | | | | Left at column 0 wraps to the last column (and vice-versa); up at the top row wraps to the bottom (and vice-versa). Makes reaching far keys quicker - e.g. the Enter/space area is one UP away from the top row.
* osk: toggle-able on-screen keyboard on the window layeruser5 days5-7/+411
| | | | | | | | | | | | | | | | | | | | | | | | | | A joypad-driven keyboard that costs zero permanent screen space: it lives on the GB window layer, so SELECT just flips LCDC bit 5 (window enable) and the terminal's background layer underneath is never disturbed. - src/joypad.asm: read $FF00 with edge detection (wPadCur/Prev/New). - src/osk.asm: 3x20 key grid (letters, digits, space, punctuation, plus Enter/Backspace) built once into spare bank-1 VRAM tiles (104+) and laid out on the $9C00 window map, docked to the bottom 3 rows. The highlighted key is a palette swap on its window attribute byte (CGB BG palette 1 = inverted), so moving the cursor is 1-2 attribute writes with no tile rebuilding. SELECT toggles, d-pad moves, A types. - KGetc's console poll loop now polls the joypad and osk_handle each iteration; a key press returns its byte to the reader exactly like a serial byte, so the shell is oblivious to the input source. Verified in the emulator (via --keys): SELECT shows the keyboard, the highlight tracks the d-pad, and typing "ls"+Enter runs the command and lists the files; a second SELECT hides it and reclaims the full 18 rows. Known limitation: the OSK overlays the bottom 3 terminal rows, so if the prompt has scrolled to the very bottom the current input line can be hidden. A follow-up can add a scroll region (terminal uses rows 0-14 while the OSK is up). Input over serial still works unchanged.
* syscall: mirror console output to the LCD terminaluser5 days3-2/+18
| | | | | | | | | | | | | | | | | | KPutc's console path now renders each byte on the LCD terminal via term_putc in addition to the serial write. Serial is kept so scripted tests still capture output (and for link-cable/debug), while the shell, command output, and echoed input now appear on-screen in the 40-col font with a live cursor and scrolling. Dropped the boot-time term_demo; the terminal starts blank and fills from real console traffic. term_putc now saves/forces/restores SVBK=1 so it always reads and writes the terminal buffer/state in WRAM bank 1, regardless of which process context KPutc is invoked from (defensive; all procs currently use bank 1). The stack lives in non-banked WRAM, so saving SVBK across the switch is safe. Verified: a headless run of `uname; ls; echo hello world` renders each prompt, the echoed command, and its output on the LCD (captured via the new `--headless --shot` path), and serial capture is unchanged.
* term: cursor + O(1) line scrollinguser5 days2-209/+455
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rework the terminal from a static one-tile-per-screen-position model to LINE-BOUND tiles with an assign[] indirection, so scrolling is cheap: - Each line-slot L owns the 20 VRAM tiles at positions [L*20..L*20+19]. - assign[screen_row] -> line-slot; the tilemap points each screen row at its slot's tiles. - Scroll = rotate assign[], blank+rebuild only the new bottom line (20 tiles), and rewrite the tilemap. O(1 line) instead of rebuilding all 360 tiles. - term_putc: printable + \n \r \b, line wrap at col 40, cursor advance with scroll-on-overflow. - Cursor: an underline OR'd into the current cell's tile via wCurMask (no sprites/OAM); moving it just re-renders the old and new tiles. - term_demo drives 24 lines through term_putc to exercise scroll+cursor. Also fixes a vicious bug this shook out: build_tile advanced its 16-bit glyph pointers with `ld hl, wGlyphL+1 / inc [hl]`, which CLOBBERS HL -- and HL is the live VRAM destination pointer. Whenever a glyph's 8 bytes straddled a page boundary (common with long/varied lines) the next tile bytes were written into WRAM at $D580+, corrupting wGlyphL/wVram/wCurRow/ wCurCol and freezing the display. Now the pointers are bumped via A so HL is preserved. (Note: the emulator build had also been silently failing on an unrelated debug edit, masking this for a while.) Verified by screenshot: 24 lines scroll to show the last 18 + a visible cursor at the "ready$" prompt; serial shell and filesystem still work.
* font: full mixed-case + punctuation glyph set (not uppercase-only)user5 days2-102/+102
| | | | | | | | | | | | | | Replace the small-caps placeholder font with a real baseline-aligned 4x8 set covering all 96 printable ASCII: distinct lowercase with true ascenders (b d f h k l t) and descenders (g j p q y), digits, and punctuation. Metrics: caps/ascenders rows 1-5, x-height rows 2-5, baseline row 5, descenders into rows 6-7. Glyphs are ~3px wide in the 4px cell -- cramped but legible; the tile mechanism itself imposes no character-set limit. genfont.py now takes per-glyph (top, rows) so glyphs sit on the baseline. Demo strings in term_test updated to show mixed case + punctuation. Verified by screenshot: descenders visibly drop below the baseline.
* term: 40-column text terminal on the CGB LCD (4x8 dynamic tiles)user5 days3-0/+482
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a background-tile text terminal that packs TWO 4px-wide characters into each 8x8 tile, giving a 40x18 grid instead of the 20x18 you'd get from an 8x8 font. The tilemap is static (one dedicated VRAM tile per screen position); we rebuild a tile's 16 bytes from two glyphs whenever a character changes. 360 tiles exceed the 256 a single tilemap can address, so positions 256-359 live in VRAM bank 1 via the CGB tilemap attribute bank-bit -- hence CGB-only. - Switch the ROM to CGB (rgbfix -C). Safe for the FS: every process has PROC_WRAMB=1, so SVBK stays on bank 1 and the WRAMX FS caches don't move. - CGB BG palette 0 = white bg / black text via BCPS/BCPD. - src/term.asm: term_init (palette + static tilemap + clear buffer), build_tile (combine two 4px glyphs -> one 8x8 tile, correct VRAM bank), term_redraw (rebuild all tiles), term_puts, term_show, term_test. - src/font.asm: 96-glyph 3x5-in-4x8 font, generated by tools/genfont.py. - 40x18 text buffer at $D600 (WRAMX, above the FS caches). - tools/ppmview.py: render a --shot PPM as ASCII so the LCD is inspectable from the shell during development. Verified via emulator screenshot: "GBOS TERMINAL", the alphabet, and a bank-1 row all render legibly at 40 columns. Serial shell + filesystem still work unchanged. Note: a full term_redraw builds 360 tiles and takes ~8 frames; fine for incremental single-char updates, but scrolling needs a smarter path (next milestone). Input (no keyboard) is also still TODO.
* fs: reject open()/read() on a directory (EISDIR)user6 days1-0/+10
| | | | | | | | open() now checks the target's inode type: opening a directory as a file returns $FE (EISDIR) instead of a valid fd, so 'cat docs' no longer streams the raw directory block as bytes. cat reports 'is a directory'; wc/head/save treat any invalid fd (>3) as an open failure. (ls is unaffected - it uses the structural opendir/list path, not open/getb.)
* fs rewrite stage 3: nested directories, paths, cwd (cd/mkdir/ls)user6 days5-36/+360
| | | | | | | | | | | | | | | | - directories generalized: dir_find/dir_add/dir_remove take any dir inode; every dir carries '.'/'..'. Path resolution (resolve / resolve_parent) walks absolute or cwd-relative paths; open/mkdir/chdir/remove/opendir take paths. - per-process cwd: PROC_CWD in the PCB (root by default, inherited on fork); sys_chdir sets it, sys_opendir points ls at any directory. - shell: 'cd' builtin + cwd-aware prompt; 'mkdir'/'ls <dir>' tools; 'exit'/'quit' and EOF call poweroff() (clean shutdown via the $ED opcode -> reliable save). - three HL/buffer-clobber bugs fixed along the way: resolve didn't preserve the path cursor across dir_find; cur_cwd clobbered HL; resolve_parent set the final name before resolve() overwrote wFsNameBuf (now copied after). - verified: nested mkdir/cd/save, multi-level paths (cat docs/sub/b), and the whole tree persists across a reboot. - README: document directories + the poweroff opcode.
* fs rewrite stage 2: inodes + root directory (block-based, persistent)user6 days4-260/+616
| | | | | | | | | | | | | | | | - fs.asm: a real block filesystem on the persistent block device - superblock, block/inode bitmaps, a 32-entry inode table (type, size, 8 direct block pointers -> files up to 2 KiB), and a root directory of 16-byte entries. Metadata cached in WRAMX; one-block data cache streams file/dir blocks. - same syscall interface (open/getb/putb/list/remove) -> tools unchanged; ls now enumerates until flist() runs out (16 files, was hardcoded 8). - old 8-slot WRAM FS removed; cart RAM partitioned: process banks 0-7, disk 8-11. - two register-clobber bugs fixed: alloc_block/alloc_inode returned the bitmap-block number (write_bitmap clobbers C); db_use loaded the wrong block on a transition (db_flush->write_block clobbers C) -> multi-block files broke. - verified: 10+ files, multi-block (300-byte) files, delete, and persistence across reboots. Debug 'blk' disk tool retained (fill/peek). - README: document the block filesystem.
* fs rewrite stage 1: persistent block device (bounce buffer, cart SRAM)user6 days4-1/+178
| | | | | | | | | | | | | | - blk.asm: read_block/write_block move 256-byte blocks between battery-backed cart-RAM banks (8-11, the 'disk') and a WRAM bounce buffer. Banking is hidden in those two routines; they inline the 'restore my bank' step so they never touch the stack while the disk bank is mapped over the process's $A000 window (the stack lives there too -- a call/ret would rug-pull it). - format-on-first-boot: superblock magic in block 0; otherwise the disk persists. - cart RAM bumped to 128 KiB (-r 4); process banks 0-7, disk banks 8-11. - debug tool 'blk fill/peek' + syscalls to validate round-trip and persistence. - verified: round-trip incl. cross-bank (block 100 -> bank 11); block survives a reboot via .sav; magic intact (no reformat on 2nd boot). - old WRAM 8-slot FS still backs the tools until stages 2-3.
* jobs: background execution (&), non-blocking reap, spin demouser6 days2-0/+65
| | | | | | | | | | | - sys_reap: nohang reap of a finished zombie child (-> pid or 0). - shell: 'cmd &' launches in the background (prints [pid], no wait); reaps finished jobs at the prompt ([pid done]). Foreground now waits for its own child specifically (loops wait(), reporting bg completions meanwhile) so kill reports the right pid. - spin: a process that yields forever - a target for ps/kill. - verified: spin &; ps shows it; kill <pid> removes just that one; immortal init; self-finishing bg worker reaped with [pid done].
* kill + ps: implement SYS_KILL (pid 1 immortal) and a ps tooluser6 days4-3/+202
| | | | | | | | | | | - PCB gains PROC_PROG (running program id), set by exec, inherited on fork. - sys_kill(pid): reject pid 1 (immortal) and unknown/dead pids; mark the target zombie, reparent its children to init, wake its parent if blocked in wait; schedule away if a process kills itself. Reuses FindPcbByPid/ReparentToInit. - sys_ps(slot,buf)->{pid,state,prog}; sys_progname(id) via NameTable reverse lookup. NameTable gains sh/ps/kill. - libc: kill/psget/progname; tools ps (pid state cmd) and kill <pid>. - verified: ps lists sh(B)+ps(R); kill 1 refused; kill 42 fails.
* shell: I/O redirection (>/<) and pipes (|); rewrite shell in Cuser6 days4-154/+193
| | | | | | | | | | | | | - kernel I/O routing: PCB gains PROC_STDIN/PROC_STDOUT (default console $FF), inherited across fork. KGetc/KPutc route read/write/putc to the console or a file fd. New syscalls: putc(16), setin(17), setout(18), lookup(19). read/write now go through the routing; putc/puts/nl use SYS_PUTC. - sys_lookup + NameTable move command-name resolution into the kernel. - shell rewritten in C (c/sh.c): tokenizes a line, parses > / < / |, and drives fork+setin/setout+exec+wait. Pipes run as 'a > __pipe ; b < __pipe' (temp file). asm shell + cmdtab removed; StrEqual/SkipName kept for sys_lookup. - libc: fork/exec/wait/setin/setout/lookup wrappers. - verified: echo>file, cat file, wc<file, cat readme|wc -l, echo ...|wc.
* filesystem: a RAM FS (WRAMX) + ls/cat/save/rm; wc/head read filesuser6 days5-2/+486
| | | | | | | | | | | - fs.asm: 8-slot RAM filesystem in WRAMX ($D000-$DFFF), name[8]+len[2]+data[502]; syscalls open/close/getb/putb/list/remove, seeded with a 'readme' at boot. - libc: open/close/fgetc/fputc/flist/fremove wrappers + O_READ/O_WRITE/NOFD. - tools: ls, save (stdin->file, one line), rm; cat/wc/head now take a file arg. - fix: syscall dispatch clobbers A, so putb takes its byte in E (was reading the handler's low address byte, 0xDC); ls NUL-terminates 8-char names. - verified: save/cat/ls/rm cycle; wc readme -> '2 7 38'; head -n 1 readme. - README: document the filesystem + the A-clobber ABI note.
* tools: wc, head, and an argc/argv demo (args) + libc.c helpersuser6 days1-0/+21
| | | | | | | | | | - c/libc.c: shared C helpers linked into every program - putu (print decimal), atou (parse decimal), argv_parse (tokenize getargs() into argc/argv). - wc: count lines/words/chars of stdin. head [n]: first n lines (drains rest to EOF). args: argc/argv demo. - pid now uses libc putu; build.sh links libc.c; Makefile CBLOBS + libc dep. - README: document the new tools + argv_parse. - verified: 'args one two three' -> argc=3/argv[..]; wc '2 3 16'; head 2.
* libc + CLI tools: a small C userlanduser6 days1-3/+68
| | | | | | | | | | | - libc: add putc, puts, strlen, getargs (args string), EOF (=4) for readc. - args: shell splits the command line at the first space ("cmd\0args\0" at $A000, inherited by the child via fork); getargs() returns the arg string. - shell: exit on Ctrl-D/EOF; $ prompt over a clean read loop. - tools (c/): echo (argv), cat (stdin->stdout to EOF), uname, pid (decimal print), true, false. Each built to a ROM-bank blob and registered. - Makefile: CBLOBS list builds all C programs. - README: document libc + the tool set.
* C toolchain: run SDCC-compiled C programs as gbos processesuser6 days1-0/+13
| | | | | | | | | | | | | - c/{gbos.h,crt0.s,libc.s,build.sh}: SDCC sm83 -> ROM-bank blob toolchain. libc syscall wrappers save/restore BC/DE/HL around rst $30 (trap clobbers them; SDCC expects them preserved). - build via SDCC native asxxxx path (sdasgb/sdldgb), crt0 linked first so _start is the $4000 entry; blob INCBIN'd into a ROM bank. - chello.c: prints a message + getpid() -> runs as 'chello' shell command. - Makefile: auto-build c/*.bin, track as a dep of programs.o; gitignore blobs. - README: document the C toolchain + the SDCC --asm=rgbds codegen bug that forced the native-toolchain approach. - verified: '$ chello' -> 'hello from C on gbos!' / 'my pid is 2'.
* shell working: fix syscall ABI (trap clobbers HL) + documentuser6 days1-1/+5
| | | | | | | | | | | - root cause of the read/echo corruption: SyscallTrap uses HL to index the dispatch table, so HL is clobbered across a syscall; the shell then wrote its buffer pointer's garbage into the $0000-$7FFF MBC register region, corrupting the mapper. fix: userland saves HL around sys_read (push/pop). - shell now runs commands end to end: $ hello -> hello world!, $ worker -> worker!, $ foo -> ? - README: document that syscalls clobber BC/DE/HL (return in A, B for wait); add read + shell to the syscall table.
* wip: sys_read + serial console shell (read-store bug under investigation)user6 days3-72/+177
| | | | | | | | | | | | - sys_read (SYS_READ): blocking console input via external-clock serial poll; yields while waiting. Verified working (direct-echo cat: 'hi' -> 'hi'). - shell (PROG_SH): prompt/read/parse/fork+exec+wait; worker+hello programs; StrEqual/SkipName helpers; command table. - init now execs the shell. - KNOWN BUG: storing the typed char to the line buffer at $A000 (cart RAM of an exec'd program) corrupts the following sys_read; sys_write reading $A000 also returns $3E. Kernel syscalls themselves are correct; isolating the cart-RAM / exec RAM-bank interaction next.
* kernel: complete the process lifecycle (exit/wait/reap + bank free list)user6 days6-76/+325
| | | | | | | | | | | | | | - exit(): zombie + status, reparent orphans to init, wake blocked parent, schedule away forever (resources reclaimed by the reaper) - wait(): scan for a zombie child; reap (free cart-RAM bank + PCB slot) and return pid/code; block PS_BLOCKED + yield if children still live; $FF if none - cart-RAM banks are now a free list (wBankUsed bitmap): AllocRamBank/FreeRamBank - scheduler: FindNextReady returns carry when nothing runnable; yield idles instead of blindly picking slot 0 - helpers: FindPcbByPid, ReparentToInit - demo: init forks 3 workers -> exec -> exit(pid) -> wait/reap => wwwR2R3R4! verified bank recycling with 6 workers over 3 banks (w2w3w4w5w6w7) - README: document the lifecycle + syscall status
* kernel: implement exec()user6 days4-25/+118
| | | | | | | | | | - sys_exec(B=program id): look up ProgramTable, point PROC_ROMB at the program's ROM text bank, map it into $4000-$7FFF, reset stack, jp to entry (no return) - programs.asm: two demo programs (ping/pong) ORG'd at the SAME $4000 in banks 2 and 3 - proves execution is driven purely by PROC_ROMB - demo: init forks; parent execs PROG_PING (bank2, '1'), child execs PROG_PONG (bank3, '2') -> '1212...', 2000/2000 balanced, zero garbage - README: document exec + text-in-ROM model
* kernel: implement fork()user6 days5-27/+249
| | | | | | | | | | - sys_fork: switch to a kernel stack, bump-allocate a cart-RAM bank, copy the parent's 8 KiB bank via a WRAM bounce buffer, plant a switch-in frame so the child returns 0 to the post-fork PC, fill the child PCB (shared ROM text) - add AllocRamBank (bump allocator) + FindFreeSlot helpers - demo: init forks; parent prints P, child prints C (PCPC...); nested fork gives three distinct pids (123...) - README: document the fork mechanism, mark syscall status
* gbos scaffold: working cooperative microkernel (verified ABAB in emulator)user6 days8-0/+653
- fix ClearKernelRAM clobbering the kernel stack (only clear $C000-$CBFF) - fix SyscallTrap clobbering DE (buffer arg) during table dispatch - README: run via ~/dev/gbc --headless; note bring-up bugs