Really more of a way to try and debug the bank8k code than anything else.
Right now this is very very basic - an outline to get booting and work from.
--- /dev/null
+ASRCS = crt0.s tbblue.s tmxvideo.s
+ASRCS += tricks.s commonmem.s
+CSRCS = devtty.c devices.c main.c
+CDSRCS = discard.c
+DSRCS = ../dev/devsd.c ../dev/blkdev.c
+DDSRCS = ../dev/devsd_discard.c ../dev/mbr.c
+DZSRCS = ../dev/zx/divmmc.c ../dev/zx/zxkeyboard.c ../dev/zx/devinput.c
+DDZSRCS =
+NSRCS = ../dev/net/net_native.c
+
+COBJS = $(CSRCS:.c=.rel)
+CDOBJS = $(CDSRCS:.c=.rel)
+AOBJS = $(ASRCS:.s=.rel)
+DOBJS = $(patsubst ../dev/%.c,%.rel, $(DSRCS))
+DDOBJS = $(patsubst ../dev/%.c,%.rel, $(DDSRCS))
+DZOBJS = $(patsubst ../dev/zx/%.c,%.rel, $(DZSRCS))
+DDZOBJS = $(patsubst ../dev/zx/%.c,%.rel, $(DDZSRCS))
+NOBJS = $(patsubst ../dev/net/%.c,%.rel, $(NSRCS))
+
+OBJS = $(COBJS) $(CDOBJS) $(AOBJS) $(DOBJS) $(DDOBJS) $(DZOBJS) $(DDZOBJS) $(NOBJS)
+
+CROSS_CCOPTS += -I../dev/ -I../dev/zx/ -I../dev/net/
+
+all: $(OBJS)
+
+$(COBJS): %.rel: %.c
+ $(CROSS_CC) $(CROSS_CCOPTS) -c $<
+
+$(CDOBJS): %.rel: %.c
+ $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGDISC) -c $<
+
+$(DOBJS): %.rel: ../dev/%.c
+ $(CROSS_CC) $(CROSS_CCOPTS) -c $<
+
+$(DDOBJS): %.rel: ../dev/%.c
+ $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGDISC) -c $<
+
+$(DZOBJS): %.rel: ../dev/zx/%.c
+ $(CROSS_CC) $(CROSS_CCOPTS) -c $<
+
+$(DDZOBJS): %.rel: ../dev/zx/%.c
+ $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGDISC) -c $<
+
+$(NOBJS): %.rel: ../dev/net/%.c
+ $(CROSS_CC) $(CROSS_CCOPTS) -c $<
+
+$(AOBJS): %.rel: %.s
+ $(CROSS_AS) $(ASOPTS) $<
+
+clean:
+ rm -f $(OBJS) *.lst *.asm *.sym *.rst *.rel core *~
+ rm -f FUZIX FUZIX.BIN load-esx.ihx load-esx.tmp
+
+image:
+ # Build an esxdos friendly setup
+ sdasz80 -o load-esx.s
+ sdldz80 -i load-esx.rel
+ makebin -s 8704 load-esx.ihx load-esx.tmp
+ # Generate the image file we need
+ dd if=load-esx.tmp of=FUZIX bs=8192 skip=1
+
+ dd if=/dev/zero bs=256 count=1 >FUZIX.BIN
+ cat ../fuzix.bin >>FUZIX.BIN
--- /dev/null
+First wild guesses at TBBlue support
+
+8K paging also needs debug
+
+Currently goal is
+
+load kernel into pages 16-23
+switch 16-22 into memory
+jump to kernel 0x0100
+switch 23 into memory
+set up and go
+
+TODO:
+DONE program_vectors
+DONE review where font and video code needs to land
+ Use nextreg
+ memory sizing
+DONEish set up page map properly
+
+ See if we can make it boot
+
+
+Bigger issues
+- We actually want a banked kernel so that we can put networking in its
+ own bank and maybe external buffers. We have tons of RAM and fast DMA.
+- Need to look at optimal inter bank copies for user copying and buffers.
+
+
--- /dev/null
+;
+; Multiple app sizes and the fact the kernel and apps share the same banks
+; means we need to put this somewhere low
+;
+ .module commonmem
+ .area _COMMONDATA
+
+ .include "../cpu-z80/std-commonmem.s"
--- /dev/null
+/* Enable to make ^Z dump the inode table for debug */
+#undef CONFIG_IDUMP
+/* Enable to make ^A drop back into the monitor */
+#undef CONFIG_MONITOR
+/* Profil syscall support (not yet complete) */
+#undef CONFIG_PROFIL
+/* Multiple processes in memory at once */
+#define CONFIG_MULTI
+/* Single tasking */
+#undef CONFIG_SINGLETASK
+
+/* Select a banked memory set up */
+#define CONFIG_BANK8 /* 8K pages */
+#define MAX_MAPS 96 /* Assume 512K for now FIXME */
+/* How big is each bank - in our case 8K */
+#define MAP_SIZE 0x2000
+#define TOP_SIZE 0x200 /* Udata to swap */
+/* How many banks do we have in our address space */
+#define CONFIG_BANKS 8 /* 8 x 8K will fix when do paging */
+#define PAGE_INVALID 0xFF /* A never used value */
+
+/* Input layer support */
+#define CONFIG_INPUT
+#define CONFIG_INPUT_GRABMAX 3
+/* Video terminal, not a serial tty */
+#define CONFIG_VT
+/* Keyboard contains non-ascii symbols */
+#define CONFIG_UNIKEY
+#define CONFIG_FONT8X8
+#define CONFIG_FONT8X8SMALL
+/* Vt definitions */
+#define VT_WIDTH 64
+#define VT_HEIGHT 24
+#define VT_RIGHT 63
+#define VT_BOTTOM 23
+
+
+
+/*
+ * Define the program loading area (needs to match kernel.def)
+ */
+#define PROGBASE 0x0000 /* Base of user */
+#define PROGLOAD 0x0100 /* Load and run here */
+#define PROGTOP 0xE000 /* Top of program, base of U_DATA stash */
+#define PROC_SIZE 56 /* Memory needed per process including stash */
+
+/*
+ * Definitions for swapping - we don't need swap!
+ */
+
+/* What is the maximum number of /dev/hd devices we have. In theory right now
+ it's actually 1 - the SD interface */
+#define MAX_BLKDEV 2
+/* Select IDE disk support, and PPIDE (parallel port IDE) as the interface */
+#define CONFIG_SD
+#define SD_DRIVE_COUNT 1
+
+#define BOOTDEVICENAMES "hd#"
+
+/* We will resize the buffers available after boot. This is the normal setting */
+#define CONFIG_DYNAMIC_BUFPOOL
+/* Larger transfers (including process execution) should go directly not via
+ the buffer cache. For all small (eg bit) systems this is the right setting
+ as it avoids polluting the small cache with data when it needs to be full
+ of directory and inode information */
+#define CONFIG_LARGE_IO_DIRECT
+
+/* Specify this if there is a real time clock capable of reporting seconds. It
+ will be used to lock the kernel time better to reality. Other details like
+ Y2K support, or even supporting dates as well don't matter */
+#undef CONFIG_RTC
+/* Specify that there is a full real time clock that can supply the date and
+ time to the system. */
+#undef CONFIG_RTC_FULL
+
+/*
+ * How fast does the clock tick (if present), or how many times a second do
+ * we simulate if not. For a machine without video 10 is a good number. If
+ * you have video you probably want whatever vertical sync/blank interrupt
+ * rate the machine has. For many systems it's whatever the hardware gives
+ * you.
+ *
+ * Note that this needs to be divisible by 10 and at least 10. If your clock
+ * is a bit slower you may need to fudge things somewhat so that the kernel
+ * gets 10 timer interrupt calls per second.
+ */
+#define TICKSPERSEC 10 /* Ticks per second */
+
+/* Core networking support */
+#define CONFIG_NET
+/* Or native (eg SLIP) */
+#define CONFIG_NET_NATIVE
+
+/*
+ * The device (major/minor) for the console and boot up tty attached to
+ * init at start up. 512 is the major 2, so all the tty devices are
+ * 512 + n where n is the tty.
+ */
+#define BOOT_TTY (512 + 1) /* Set this to default device for stdio, stderr */
+ /* In this case, the default is the first TTY device */
+/*
+ * If you have a mechanism to pass in a root device configuration then
+ * this holds the address of the buffer (eg a CP/M command line or similar).
+ * If the configuration is fixed then this can be a string holding the
+ * configuration. NULL means 'prompt the user'.
+ */
+#define CMDLINE NULL /* Location of root dev name */
+
+/* Device parameters */
+#define NUM_DEV_TTY 2 /* How many tty devices does the platform support */
+#define TTYDEV BOOT_TTY /* Device used by kernel for messages, panics */
+#define NBUFS 5 /* Number of block buffers. Must be 4+ and must match
+ kernel.def */
+#define NMOUNTS 4 /* Number of mounts at a time */
+
+/* This can optionally be set to force a default baud rate, eg if the system
+ console should match a firmware set rate */
+#define TTY_INIT_BAUD B38400 /* To match ROMWBW */
+
--- /dev/null
+ .module crt0
+
+ .area _CODE
+ .area _CODE2
+ .area _CODE3
+ .area _VIDEO
+ .area _INITIALIZED
+ .area _HOME
+ .area _CONST
+
+ ;
+ ; Beyond this point we just zero.
+ ;
+
+ .area _DATA
+ .area _BSEG
+ .area _BSS
+ .area _HEAP
+ .area _GSINIT
+ .area _GSFINAL
+ ;
+ ; Finally the buffers so they can expand
+ ;
+ .area _BUFFERS
+ .area _INITIALIZER
+
+ .area _DISCARD
+ ; Somewhere to throw it out of the way
+
+
+ ; Our common is mapped high
+ .area _COMMONDATA
+ .area _COMMONMEM
+ .area _FONT
+
+
+
+ ; imported symbols
+ .globl _fuzix_main
+ .globl init_early
+ .globl init_hardware
+ .globl l__BUFFERS
+ .globl s__BUFFERS
+ .globl l__DATA
+ .globl s__DATA
+ .globl kstack_top
+
+ .globl unix_syscall_entry
+ .globl nmi_handler
+ .globl interrupt_handler
+
+ .include "../kernel.def"
+ .include "kernel.def"
+
+ ;
+ ; startup code. Runs from 0x100. The kernel is mapped into pages
+ ; 16-23 and 16-22 are currently mapped. Stack is not valid on entry
+ ; and interrupts are off.
+ ;
+
+ .area _CODE
+
+ .globl _start
+
+_start:
+ ; Map in the top page (it couldn't be mapped by the loader as the
+ ; loader is living in it)
+ ld a,#0x57 ; MMU E000-FFFF
+ ld bc,#0x243B
+ out (c),a
+ ld a,#23 ; Top kernel page
+ inc b
+ out (c),a
+
+ ; We need to wipe the BSS but the rest of the job is done.
+
+ ld hl, #s__DATA
+ ld de, #s__DATA+1
+ ld bc, #l__DATA-1
+ ld (hl), #0
+ ldir
+ ld hl, #s__BUFFERS
+ ld de, #s__BUFFERS+1
+ ld bc, #l__BUFFERS-1
+ ld (hl), #0
+ ldir
+
+ ld sp, #kstack_top
+
+ ; Configure memory map
+ call init_early
+
+ ; Hardware setup
+ call init_hardware
+
+ ; Call the C main routine
+ call _fuzix_main
+
+ ; main shouldn't return, but if it does...
+ di
+stop: halt
+ jr stop
+
+ .area _BUFFERS
+;
+; Buffers (we use asm to set this up as we need them in a special segment
+; so we can recover the discard memory into the buffer pool
+;
+
+ .globl _bufpool
+ .area _BUFFERS
+
+_bufpool:
+ .ds BUFSIZE * NBUFS
--- /dev/null
+#include <kernel.h>
+#include <version.h>
+#include <kdata.h>
+#include <tty.h>
+#include <devsys.h>
+#include <vt.h>
+#include <devsd.h>
+#include <blkdev.h>
+#include <devtty.h>
+
+struct devsw dev_tab[] = /* The device driver switch table */
+{
+ /* 0: /dev/hd Hard disc block devices */
+ { blkdev_open, no_close, blkdev_read, blkdev_write, blkdev_ioctl },
+ /* 1: /dev/fd Floppy disc block devices: nope */
+ { no_open, no_close, no_rdwr, no_rdwr, no_ioctl },
+ /* 2: /dev/tty TTY devices */
+ { tty_open, tty_close, tty_read, tty_write, gfx_ioctl },
+ /* 3: /dev/lpr Printer devices */
+ { no_open, no_close, no_rdwr, no_rdwr, no_ioctl },
+ /* 4: /dev/mem etc System devices (one offs) */
+ { no_open, no_close, sys_read, sys_write, sys_ioctl },
+ /* 5: Pack to 7 with nxio if adding private devices and start at 8 */
+};
+
+bool validdev(uint16_t dev)
+{
+ /* This is a bit uglier than needed but the right hand side is
+ a constant this way */
+ if(dev > ((sizeof(dev_tab)/sizeof(struct devsw)) << 8) - 1)
+ return false;
+ else
+ return true;
+}
+
+void device_init(void)
+{
+#ifdef CONFIG_SD
+ devsd_init();
+#endif
+}
--- /dev/null
+#include <kernel.h>
+#include <kdata.h>
+#include <printf.h>
+#include <stdbool.h>
+#include <devtty.h>
+#include <keycode.h>
+#include <vt.h>
+#include <tty.h>
+#include <graphics.h>
+#include <input.h>
+#include <devinput.h>
+
+char tbuf1[TTYSIZ];
+
+uint8_t vtattr_cap = VTA_INVERSE|VTA_FLASH|VTA_UNDERLINE;
+extern uint8_t curattr;
+
+static tcflag_t console_mask[4] = {
+ _ISYS,
+ _OSYS,
+ _CSYS,
+ _LSYS
+};
+
+tcflag_t *termios_mask[NUM_DEV_TTY + 1] = {
+ NULL,
+ console_mask
+};
+
+
+struct s_queue ttyinq[NUM_DEV_TTY + 1] = { /* ttyinq[0] is never used */
+ {NULL, NULL, NULL, 0, 0, 0},
+ {tbuf1, tbuf1, tbuf1, TTYSIZ, 0, TTYSIZ / 2},
+};
+
+/* tty1 is the screen */
+
+/* Output for the system console (kprintf etc) */
+void kputchar(char c)
+{
+ if (c == '\n')
+ tty_putc(0, '\r');
+ tty_putc(0, c);
+}
+
+/* Both console and debug port are always ready */
+ttyready_t tty_writeready(uint8_t minor)
+{
+ minor;
+ return TTY_READY_NOW;
+}
+
+void tty_putc(uint8_t minor, unsigned char c)
+{
+ minor;
+ vtoutput(&c, 1);
+}
+
+int tty_carrier(uint8_t minor)
+{
+ minor;
+ return 1;
+}
+
+void tty_setup(uint8_t minor, uint8_t flags)
+{
+ minor;
+}
+
+void tty_sleeping(uint8_t minor)
+{
+ minor;
+}
+
+void tty_data_consumed(uint8_t minor)
+{
+}
+
+
+/* This is used by the vt asm code, but needs to live in the kernel */
+uint16_t cursorpos;
+
+/* For now we only support 64 char mode - we should add the mode setting
+ logic an dother modes FIXME */
+static struct display specdisplay = {
+ 0,
+ 512, 192,
+ 512, 192,
+ 0xFF, 0xFF,
+ FMT_TIMEX64,
+ HW_UNACCEL,
+ GFX_VBLANK|GFX_MAPPABLE|GFX_TEXT,
+ 0
+};
+
+static struct videomap specmap = {
+ 0,
+ 0,
+ 0x4000,
+ 14336,
+ 0,
+ 0,
+ 0,
+ MAP_FBMEM|MAP_FBMEM_SIMPLE
+};
+
+/*
+ * Graphics ioctls. Very minimal for this platform. It's a single fixed
+ * mode with direct memory mapping.
+ */
+int gfx_ioctl(uint8_t minor, uarg_t arg, char *ptr)
+{
+ if (minor != 1 || arg >> 8 != 0x03)
+ return vt_ioctl(minor, arg, ptr);
+ switch(arg) {
+ case GFXIOC_GETINFO:
+ return uput(&specdisplay, ptr, sizeof(struct display));
+ case GFXIOC_MAP:
+ return uput(&specmap, ptr, sizeof(struct videomap));
+ case GFXIOC_UNMAP:
+ return 0;
+ case GFXIOC_WAITVB:
+ /* Our system clock is vblank */
+ timer_wait++;
+ psleep(&timer_interrupt);
+ timer_wait--;
+ chksigs();
+ if (udata.u_cursig) {
+ udata.u_error = EINTR;
+ return -1;
+ }
+ return 0;
+ }
+ return -1;
+}
+
+void vtattr_notify(void)
+{
+ /* Attribute byte fixups: not hard as the colours map directly
+ to the spectrum ones */
+ if (vtattr & VTA_INVERSE)
+ curattr = ((vtink & 7) << 3) | (vtpaper & 7);
+ else
+ curattr = (vtink & 7) | ((vtpaper & 7) << 3);
+ if (vtattr & VTA_FLASH)
+ curattr |= 0x80;
+ /* How to map the bright bit - we go by either */
+ if ((vtink | vtpaper) & 0x10)
+ curattr |= 0x40;
+}
--- /dev/null
+#ifndef __DEVTTY_DOT_H__
+#define __DEVTTY_DOT_H__
+
+void tty_pollirq(void);
+static void keydecode(void);
+
+#define KEY_ROWS 8
+#define KEY_COLS 5
+extern uint8_t keymap[8];
+extern uint8_t keyboard[8][5];
+extern uint8_t shiftkeyboard[8][5];
+
+extern uint8_t timer_wait;
+
+extern int gfx_ioctl(uint8_t minor, uarg_t arg, char *ptr);
+
+extern uint8_t vtborder;
+
+#endif
--- /dev/null
+#include <kernel.h>
+#include <timer.h>
+#include <kdata.h>
+#include <printf.h>
+#include <devtty.h>
+#include <blkdev.h>
+
+extern uint8_t kempston, kmouse;
+
+uint8_t platform_param(char *p)
+{
+ return 0;
+}
+
+/* Nothing to do for the map of init */
+void map_init(void)
+{
+}
+
+void pagemap_init(void)
+{
+ uint8_t i;
+ /* 8K pages that are above the kernel */
+ /* FIXME: will depend upon size (<160 or < 224 for expanded) */
+ for (i = 24; i < 96; i++)
+ pagemap_add(i);
+ /* We can arguably also steal the memory wasted on the DivMMC
+ that we don't use FIXME */
+
+ /* Low pages we can scavenge */
+ /*
+ Reserved
+ 10-11: system screen (console 1)
+ 14-15: shadow screen (console 2)
+
+ We should probably reserve Layer 2 buffers as well at some
+ point in time
+ */
+ for (i = 0; i < 10; i++)
+ pagemap_add(i);
+ pagemap_add(12);
+ pagemap_add(13);
+ /* Common for init */
+ pagemap_add(23);
+}
+
+void platform_copyright(void)
+{
+ kempston = 1;
+ kmouse = 1;
+}
+
--- /dev/null
+-mwxuy
+-i fuzix.ihx
+-l z80
+-b _CODE=0x0100
+-b _COMMONDATA=0xF200
+-b _DISCARD=0xE200
+platform-tbblue/crt0.rel
+platform-tbblue/commonmem.rel
+platform-tbblue/tbblue.rel
+platform-tbblue/tmxvideo.rel
+platform-tbblue/main.rel
+platform-tbblue/discard.rel
+start.rel
+version.rel
+lowlevel-z80.rel
+usermem_std-z80.rel
+platform-tbblue/tricks.rel
+timer.rel
+kdata.rel
+usermem.rel
+platform-tbblue/devices.rel
+devio.rel
+filesys.rel
+process.rel
+inode.rel
+syscall_exec16.rel
+syscall_fs.rel
+syscall_fs2.rel
+syscall_fs3.rel
+syscall_proc.rel
+syscall_other.rel
+syscall_net.rel
+tty.rel
+vt.rel
+font8x8.rel
+mm.rel
+bank8k.rel
+swap.rel
+devsys.rel
+devinput.rel
+platform-tbblue/devtty.rel
+platform-tbblue/devsd.rel
+platform-tbblue/devsd_discard.rel
+platform-tbblue/divmmc.rel
+platform-tbblue/mbr.rel
+platform-tbblue/blkdev.rel
+platform-tbblue/devinput.rel
+platform-tbblue/zxkeyboard.rel
+platform-tbblue/net_native.rel
+-e
--- /dev/null
+U_DATA .equ 0xF000 ; (this is struct u_data from kernel.h)
+U_DATA__TOTALSIZE .equ 0x200 ; 256+256 bytes.
+
+Z80_TYPE .equ 1
+
+PROGBASE .equ 0x0000
+PROGLOAD .equ 0x0100
+
+NBUFS .equ 5
+
+Z80_MMU_HOOKS .equ 0
--- /dev/null
+;
+; TBBlue bootstrap via ESXDOS API
+;
+; We are loaded at 0x2000. We load the kernel into banks 16-23 and
+; then map most of it in and jump to 0x0100 in the loaded image
+;
+; As we use higher pages we know that we can return to BASIC and
+; stuff like the RAMdisc will remain intact.
+;
+
+ .area _BOOT(ABS)
+ .org 0x2000
+
+ ; We get run with a valid SP but it's lurking in high space so
+ ; move sp for banking.
+start:
+ ld (escape),sp
+ ld sp,#0x8000
+ xor a
+ rst 8
+ .db 0x89
+ ld (drive),a
+
+ ld hl, #filename
+ ld b, #0x01
+ ld a,(drive)
+
+ rst 8
+ .db 0x9A
+
+ jr c, failure
+
+ ld (handle),a
+
+ ;
+ ; We load the image into high pages so that if we barf
+ ; everything is good even the ramdisc.
+ ;
+ ld a,#16 ; Stuff the first 16K in bank 16/17
+ ld hl,#0xC000
+ call load16k
+
+ ld a,#18 ; Second bank into 18/19
+ call load16k
+
+ ld a,#20 ; Third bank
+ call load16k
+
+ ld a,#22
+ call load16k ; Fourth bank
+
+ ld a,(handle)
+ rst 8
+ .db 0x9B ; Close
+
+ ld hl,#strap
+ ld de,#0xFF00
+ ld bc,#0x0100
+ ldir
+
+ ; Now the delicate bit of the operation - taking over the DivMMC/IDE
+ ; ROM image
+
+ ld hl,#0xFF00
+ rst 0x20 ; Terminate esxdos command and return to
+ ; our bootstrap code we just moved
+
+load16k:
+ ld bc,#0x243B
+ ld e,#0x56 ; 0xC000 mapping register
+ out (c),e
+ inc b
+ out (c),a ; Page requested
+ inc b
+ out (c),b ; MMU register 7
+ dec b ; back to control port
+ inc e ; next register
+ inc a ; next page
+ out (c),e
+ inc b
+ out (c),a
+
+ ld a,(handle) ; Load 16K into that page
+ ld bc,#0x4000
+ ld hl,#0xC000 ; We mapped it at 48K up
+ rst 8
+ .byte 0x9D
+ ret nc
+failure:
+ ld hl,#ohpoo
+fail:
+ ld a,(hl)
+ inc hl
+ or a
+ jr z, faildone
+ rst 0x10
+ jr fail
+ ; throw ourselves under the bus
+faildone:
+ ld a,(handle)
+ or a
+ jr z, noclose
+ rst 8
+ .byte 0x9B
+noclose:
+ ld sp,(escape)
+ ret
+
+ohpoo:
+ .ascii 'Unable to load Fuzix image'
+ .db 13,0
+filename:
+ .asciz 'FUZIX.BIN'
+handle:
+ .db 0
+drive:
+ .db 0
+escape:
+ .dw 0
+
+;
+; Code run from 0xFF00
+;
+strap:
+ ; We are moving interrupt vectors and stuff
+ di
+ ; Page in 16/17/18/19/20/21/22
+ ; not 23 as that will go over us. Instead the kernel entry will
+ ; fix that one up
+ ld a,#16
+ ld bc,#0x243B
+ ld de,#0x5007
+mmuset:
+ out (c),d ; register
+ inc b
+ out (c),a ; data
+ dec b
+ inc a ; next page
+ inc d ; next register
+ dec e ; are we there yet ?
+ jr nz, mmuset
+
+ jp 0x0100
--- /dev/null
+#include <kernel.h>
+#include <timer.h>
+#include <kdata.h>
+#include <printf.h>
+#include <devtty.h>
+#include <devinput.h>
+
+uint16_t ramtop = PROGTOP;
+
+/* On idle we spin checking for the terminals. Gives us more responsiveness
+ for the polled ports */
+void platform_idle(void)
+{
+ /* We don't want an idle poll and IRQ driven tty poll at the same moment */
+ __asm
+ halt
+ __endasm;
+}
+
+uint8_t timer_wait;
+
+void platform_interrupt(void)
+{
+ tty_pollirq();
+ timer_interrupt();
+ poll_input();
+ if (timer_wait)
+ wakeup(&timer_interrupt);
+}
+
+/* This points to the last buffer in the disk buffers. There must be at least
+ four buffers to avoid deadlocks. */
+struct blkbuf *bufpool_end = bufpool + NBUFS;
+
+/*
+ * We pack discard into the memory image is if it were just normal
+ * code but place it at the end after the buffers. When we finish up
+ * booting we turn everything from the buffer pool to the start of
+ * user space into buffers.
+ *
+ * Discard gets turned into buffers or user space
+ */
+void platform_discard(void)
+{
+ uint16_t discard_size = 0xE000 - (uint16_t)bufpool_end;
+ bufptr bp = bufpool_end;
+
+ discard_size /= sizeof(struct blkbuf);
+
+ kprintf("%d buffers added\n", discard_size);
+
+ bufpool_end += discard_size;
+
+ memset( bp, 0, discard_size * sizeof(struct blkbuf) );
+
+ for( bp = bufpool + NBUFS; bp < bufpool_end; ++bp ){
+ bp->bf_dev = NO_DEVICE;
+ bp->bf_busy = BF_FREE;
+ }
+}
+
+/* Adding dummy swapper since it is referenced by tricks.s */
+void swapper(ptptr p)
+{
+ p;
+}
--- /dev/null
+export CROSS_CC_SYS5=--codeseg CODE3
--- /dev/null
+export CPU = z80
--- /dev/null
+;
+; TBBlue hardware support
+;
+
+ .module tbblue
+
+ ; exported symbols
+ .globl init_early
+ .globl init_hardware
+ .globl _program_vectors
+ .globl platform_interrupt_all
+ .globl interrupt_handler
+ .globl unix_syscall_entry
+ .globl null_handler
+ .globl nmi_handler
+
+ .globl map_kernel
+ .globl map_process_always
+ .globl map_process
+ .globl map_kernel_di
+ .globl map_process_always_di
+ .globl map_save_kernel
+ .globl map_restore
+ .globl map_kernel_restore
+ .globl map_video
+ .globl current_map
+
+ .globl _int_disabled
+ .globl _vtborder
+
+ ; exported debugging tools
+ .globl _platform_monitor
+ .globl _platform_reboot
+ .globl outchar
+
+ ; imported symbols
+ .globl _ramsize
+ .globl _procmem
+
+ .globl _vtoutput
+ .globl _vtinit
+
+ .globl outcharhex
+ .globl outhl, outde, outbc
+ .globl outnewline
+ .globl outstring
+ .globl outstringhex
+
+ .include "kernel.def"
+ .include "../kernel.def"
+
+; -----------------------------------------------------------------------------
+; COMMON MEMORY BANK (above 0xE000)
+; -----------------------------------------------------------------------------
+ .area _COMMONMEM
+
+_platform_monitor:
+ ;
+ ; Not so much a monitor as wait for space
+ ;
+ ld a, #0x7F
+ in a, (0xFE)
+ rra
+ jr c, _platform_monitor
+
+_platform_reboot:
+ di
+ ; FIXME: put back 48K ROM
+ rst 0 ; back into our booter
+
+platform_interrupt_all:
+ ret
+
+ .area _COMMONDATA
+
+_int_disabled:
+ .db 1
+
+_vtborder: ; needs to be common
+ .db 0
+
+
+; -----------------------------------------------------------------------------
+; KERNEL CODE BANK (below 0xE000, only accessible when the kernel is mapped)
+; -----------------------------------------------------------------------------
+ .area _CODE
+
+init_early:
+ ret
+
+ .area _DISCARD
+
+init_hardware:
+ ; set system RAM size
+ ld hl, #512 ; FIXME: probe not hardcode
+ ld (_ramsize), hl
+ ld hl, #448 ; FIXME: TBD
+ ld (_procmem), hl
+
+ ; Reprogram the TBBlue registers
+
+ ld a,#0x06
+ ld de,#0x9B80 ; Turbo on, DivMMC paging off, Multiface off,
+ ; Sound mode AY
+ call tbblue_config
+
+ ld a,#0x07
+ ld de,#0x0302 ; 14Mhz
+ call tbblue_config
+
+ ld a,#0x08
+ ld de,#0xEECE ; 128K paging(?), no RAM contention, ABC stereo
+ ; Covox, Timex, Turbosound on
+ call tbblue_config
+
+ ld a,#0x09
+ ld de,#0xFC00 ; Kempston on, divMMC on
+ call tbblue_config
+
+ ld a,#0x15
+ ld de,#0xFF00 ; Lores off, sprites off, border off, normal order
+ call tbblue_config
+
+ ; Activate Timex screen
+ ld a,#0x3E
+ out (0xFF),a
+
+ ; screen initialization
+ call _vtinit
+
+ ret
+
+tbblue_config:
+ ld bc,#0x243B
+ out (c),a
+ inc b
+ ld a,d ; mask
+ cpl ; bits to keep
+ in d,(c) ; read register
+ and d ; mask out bits to change
+ or e ; mask in new bits
+ out (c),a ; write register
+ ret
+
+
+;------------------------------------------------------------------------------
+; COMMON MEMORY PROCEDURES FOLLOW
+
+ .area _COMMONMEM
+
+_program_vectors:
+ pop de
+ pop hl
+ push hl
+ push de
+ call map_process
+
+ ; write zeroes across all vectors
+ ld hl, #0
+ ld de, #1
+ ld bc, #0x007f ; program first 0x80 bytes only
+ ld (hl), #0x00
+ ldir
+
+ ; now install the interrupt vector at 0x0038
+ ld a, #0xC3 ; JP instruction
+ ld (0x0038), a
+ ld hl, #interrupt_handler
+ ld (0x0039), hl
+
+ ; set restart vector for FUZIX system calls
+ ld (0x0030), a ; (rst 30h is unix function call vector)
+ ld hl, #unix_syscall_entry
+ ld (0x0031), hl
+
+ ld (0x0000), a
+ ld hl, #null_handler ; to Our Trap Handler
+ ld (0x0001), hl
+
+ ld (0x0066), a ; Set vector for NMI
+ ld hl, #nmi_handler
+ ld (0x0067), hl
+
+ jr map_kernel
+
+map_process:
+ ld a, h
+ or l
+ jr z, map_kernel
+map_process_always:
+map_process_always_di:
+ push af
+ push bc
+ push de
+ push hl
+ ld hl,(U_DATA__U_PAGE)
+map_write_hl:
+ ; Switch this to nextreg at some point FIXME
+ ld bc,#0x243b
+ ld (current_map),hl
+ ld e,#0x0750
+map_write_loop:
+ ld a,(hl)
+ out (c),e
+ inc b
+ out (c),a
+ dec b
+ dec d
+ jr nz, map_write_loop
+ pop hl
+ pop de
+ pop bc
+ pop af
+ ret
+
+;
+; Save and switch to kernel
+;
+map_save_kernel:
+ push hl
+ ld hl, (current_map)
+ ld (map_store), hl
+ pop hl
+map_kernel_di:
+map_kernel:
+map_kernel_restore:
+ push af
+ push bc
+ push de
+ push hl
+ ld hl, #kernel_map
+ jr map_write_hl
+
+map_video:
+ push af
+ push bc
+ push de
+ push hl
+ ld hl, #video_map
+ jr map_write_hl
+
+map_restore:
+ push af
+ push bc
+ push de
+ push hl
+ ld hl, (map_store)
+ jr map_write_hl
+
+;
+; We have no easy serial debug output instead just breakpoint this
+; address when debugging.
+;
+outchar:
+ ld (_tmpout), a
+ push bc
+ push de
+ push hl
+ push ix
+ ld hl, #1
+ push hl
+ ld hl, #_tmpout
+ push hl
+ call _vtoutput
+ pop af
+ pop af
+ pop ix
+ pop hl
+ pop de
+ pop bc
+ ret
+
+ .area _COMMONDATA
+_tmpout:
+ .db 1
+
+current_map: ; place to store current page pointer
+ .dw 0
+map_store: ; and the saved one
+ .dw 0
+
+kernel_map:
+ .db 16, 17, 18, 19, 20, 21, 22
+video_map:
+ .db 16, 17, 10, 11, 20, 21, 22
--- /dev/null
+;
+; Timex VT primitives
+;
+; 512 pixel mode
+;
+; Need to move into one spot and share between tc2068/chloe/tbblue
+;
+
+ .module tmxvideo
+
+ ; exported symbols
+ .globl _plot_char
+ .globl _scroll_down
+ .globl _scroll_up
+ .globl _cursor_on
+ .globl _cursor_off
+ .globl _cursor_disable
+ .globl _clear_lines
+ .globl _clear_across
+ .globl _do_beep
+ .globl _fontdata_8x8
+ .globl _curattr
+ .globl _vtattr
+ .globl map_kernel
+ .globl map_video
+
+ ; Build the video library as the only driver
+ ; We will make this includable at some point
+
+TMXVID_ONLY .equ 1
+
+ .area _VIDEO
+
+;
+; zx128 vt primitives hacked a bit
+;
+; Will be replaced by Timex video shortly
+;
+ ; exported symbols
+ .globl tmx_plot_char
+ .globl tmx_scroll_down
+ .globl tmx_scroll_up
+ .globl tmx_cursor_on
+ .globl tmx_cursor_off
+ .globl tmx_cursor_disable
+ .globl tmx_clear_lines
+ .globl tmx_clear_across
+ .globl tmx_do_beep
+ .globl _fontdata_8x8
+ .globl _curattr
+ .globl _vtattr
+
+videopos:
+ srl d ; we alternate pixels between two screens
+ push af
+ ld a,e
+ and #7
+ rrca
+ rrca
+ rrca
+ add a,d
+ ld d,e
+ ld e,a
+ pop af
+ jr c, rightside
+ ld a,d
+ and #0x18
+ or #0x40 ; Left screen
+ ld d,a
+ jp map_video
+rightside:
+ ld a,d
+ and #0x18
+ or #0x60 ; Left screen
+ ld d,a
+ jp map_video
+
+ .if TMXVID_ONLY
+_plot_char:
+ .endif
+tmx_plot_char:
+ pop hl
+ pop de ; D = x E = y
+ pop bc
+ push bc
+ push de
+ push hl
+
+ ld hl,(_vtattr) ; l is vt attributes
+ push hl ; save attributes as inaccessible once vid mapped
+
+ call videopos
+
+ ld b, #0 ; calculating offset in font table
+ ld a, c
+
+ or a ; clear carry
+ rla
+ rl b
+ rla
+ rl b
+ rla
+ rl b
+ ld c, a
+
+ ld hl, #_fontdata_8x8-32*8 ; font
+ add hl, bc ; hl points to first byte of char data
+
+ pop bc
+ ; We do underline for now - not clear italic or bold are useful
+ ; with the font we have.
+
+ ; printing
+plot_char_loop:
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ ld (de), a
+ inc hl ; next byte of char data
+ inc d ; next screen line
+
+ ld a, (hl)
+ bit 1,c ; underline ?
+ jr nz, last_ul
+plot_attr:
+ ld (de), a
+ jp map_kernel
+
+last_ul:
+ ld a,#0xff
+ jr plot_attr
+
+ .if TMXVID_ONLY
+_clear_lines:
+ .endif
+tmx_clear_lines:
+ pop hl
+ pop de ; E = line, D = count
+ push de
+ push hl
+ ; This way we handle 0 correctly
+ inc d
+ jr nextline
+
+clear_next_line:
+ push de
+ ld d, #0 ; from the column #0
+ ld b, d ; b = 0
+ ld c, #64 ; clear 64 cols
+ push bc
+ push de
+ call _clear_across
+ pop hl ; clear stack
+ pop hl
+
+ pop de
+ inc e
+nextline:
+ dec d
+ jr nz, clear_next_line
+
+ ret
+
+
+ .if TMXVID_ONLY
+_clear_across:
+ .endif
+tmx_clear_across:
+ pop hl
+ pop de ; DE = coords
+ pop bc ; C = count
+ push bc
+ push de
+ push hl
+ ld a,c
+ or a
+ ret z ; No work to do - bail out
+ call videopos ; first pixel line of first character in DE
+
+ ; Save it in HL
+ ld h,d
+ ld l,e
+
+ xor a
+
+ ; TODO Figure out if starting L or R
+ bit 5,d
+ jr nz, clear_start_r
+
+
+ ; no boundary checks. Assuming that D + C < SCREEN_WIDTH
+clear_line:
+
+ ; Do the left character
+ ld b, #8 ; 8 pixel lines to clear for this char
+clear_char_l:
+ ld (de), a
+ inc d
+ djnz clear_char_l
+
+ ; Left was final char
+ dec c
+ jr z, lines_done
+
+ ; Recover position from HL and move 8K up
+ ld d,h
+ ld e,l
+ set 5,d
+
+clear_start_r:
+ ld b, #8 ; 8 pixel lines to clear for this char
+clear_char_r:
+ ld (de), a
+ inc d
+ djnz clear_char_r
+
+ inc hl
+ ld d,h
+ ld e,l
+
+ ; Next character ?
+ dec c
+ jr nz, clear_line
+lines_done:
+ jp map_kernel
+
+copy_line:
+ ; HL - source, DE - destination
+
+ ; convert line coordinates to screen coordinates both for DE and HL
+ push de
+ ex de, hl
+ call videopos
+ ex de, hl
+ pop de
+ call videopos
+
+ ld c, #8
+
+copy_line_nextchar:
+ push hl
+ push de
+
+ ld b, #32
+
+copy_pixel_line:
+ ld a, (hl)
+ ld (de), a
+ inc e
+ inc l
+ djnz copy_pixel_line
+
+ pop de
+ pop hl
+ push hl
+ push de
+ set 5,d ; Even half
+ set 5,h
+ ld b,#32
+copy_pixel_line_r:
+ ld a,(hl)
+ ld (de),a
+ inc e
+ inc l
+ djnz copy_pixel_line_r
+ pop de
+ pop hl
+ inc d
+ inc h
+ dec c
+ jr nz, copy_line_nextchar
+ ret
+
+ ; TODO: the LDIR way should be much faster
+
+ .if TMXVID_ONLY
+_scroll_down:
+ .endif
+tmx_scroll_down:
+ ; set HL = (0,22), DE = (0, 23)
+ xor a
+ ld d, a
+ ld h, a
+ ld l, #22
+ ld e, #23
+ ld c, #23 ; 23 lines to move
+
+ call map_video
+
+loop_scroll_down:
+ push hl
+ push de
+ push bc
+
+ call copy_line
+
+ pop bc
+ pop de
+ pop hl
+
+ dec l
+ dec e
+ dec c
+ jr nz, loop_scroll_down
+ jp map_kernel
+
+
+ .if TMXVID_ONLY
+_scroll_up:
+ .endif
+tmx_scroll_up:
+ ; set HL = (0,1), DE = (0, 0)
+ xor a
+ ld d, a
+ ld e, a
+ ld h, a
+ ld l, #1
+ ld c, #23 ; 23 lines to move
+
+ call map_video
+
+loop_scroll_up:
+ push hl
+ push de
+ push bc
+
+ call copy_line
+
+ pop bc
+ pop de
+ pop hl
+
+ inc l
+ inc e
+ dec c
+ jr nz, loop_scroll_up
+ jp map_kernel
+
+ .if TMXVID_ONLY
+_cursor_on:
+ .endif
+tmx_cursor_on:
+ pop hl
+ pop de
+ push de
+ push hl
+ ld (cursorpos), de
+
+ call videopos
+ ld a, #7
+ add a, d
+ ld d, a
+ ld a, #0xFF
+ ld (de), a
+ jp map_kernel
+ .if TMXVID_ONLY
+_cursor_disable:
+_cursor_off:
+ .endif
+tmx_cursor_disable:
+tmx_cursor_off:
+ ld de, (cursorpos)
+ call videopos
+ ld a, #7
+ add a, d
+ ld d, a
+ xor a
+ ld (de), a
+ jp map_kernel
+
+ .if TMXVID_ONLY
+_do_beep:
+ .endif
+tmx_do_beep:
+ ret
+
+ .area _DATA
+
+cursorpos:
+ .dw 0
+
+ .area _COMMONDATA
+
+_curattr:
+ .db 7
+
--- /dev/null
+; 2013-12-21 William R Sowerbutts
+
+ .module tricks
+
+ .globl _ptab_alloc
+ .globl _makeproc
+ .globl _chksigs
+ .globl _getproc
+ .globl _platform_monitor
+ .globl trap_illegal
+ .globl _platform_switchout
+ .globl _switchin
+ .globl _doexec
+ .globl _dofork
+ .globl _runticks
+ .globl unix_syscall_entry
+ .globl interrupt_handler
+ .globl map_kernel
+ .globl _need_resched
+ .globl _int_disabled
+ .globl _udata
+
+ ; imported debug symbols
+ .globl outstring, outde, outhl, outbc, outnewline, outchar, outcharhex
+
+ .include "kernel.def"
+ .include "../kernel.def"
+
+ .area _COMMONMEM
+
+_need_resched:
+ .db 0
+
+; Switchout switches out the current process, finds another that is READY,
+; possibly the same process, and switches it in. When a process is
+; restarted after calling switchout, it thinks it has just returned
+; from switchout().
+;
+; This function can have no arguments or auto variables.
+_platform_switchout:
+ ; save machine state
+
+ ld hl, #0 ; return code set here is ignored, but _switchin can
+ ; return from either _switchout OR _dofork, so they must both write
+ ; U_DATA__U_SP with the following on the stack:
+ push hl ; return code
+ push ix
+ push iy
+ ld (U_DATA__U_SP), sp ; this is where the SP is restored in _switchin
+
+ ; find another process to run (may select this one again)
+ call _getproc
+
+ push hl
+ call _switchin
+
+ ; we should never get here
+ call _platform_monitor
+
+badswitchmsg: .ascii "_switchin: FAIL"
+ .db 13, 10, 0
+
+_switchin:
+ di
+ pop bc ; return address
+ pop de ; new process pointer
+;
+; FIXME: do we actually *need* to restore the stack !
+;
+ push de ; restore stack
+ push bc ; restore stack
+
+ ld hl, #P_TAB__P_PAGE_OFFSET
+ add hl, de ; process ptr
+ ld a,(hl)
+ inc hl
+ ld h,(hl) ; page pointer
+ ld l,a
+
+ ld bc,#7
+ add hl,bc ; common
+
+ ld bc,#0x243B
+ ld a,#0x57 ; common bank MMU pointer
+ out (c),a
+
+ ld a, (hl)
+ inc b
+ out (c), a ; *CAUTION* our stack just left the building
+
+ ; ------- No stack -------
+ ; check u_data->u_ptab matches what we wanted
+ ld hl, (U_DATA__U_PTAB) ; u_data->u_ptab
+ or a ; clear carry flag
+ sbc hl, de ; subtract, result will be zero if DE==IX
+ jr nz, switchinfail
+
+ ; wants optimising up a bit
+ ld hl, #P_TAB__P_STATUS_OFFSET
+ add hl, de
+ ld (hl), #P_RUNNING
+
+ ; runticks = 0
+ ld hl, #0
+ ld (_runticks), hl
+
+ ; restore machine state -- note we may be returning from either
+ ; _switchout or _dofork
+ ld sp, (U_DATA__U_SP)
+
+ ; ---- New task stack ----
+
+ pop iy
+ pop ix
+ pop hl ; return code
+
+ ; enable interrupts, if the ISR isn't already running
+ ld a, (U_DATA__U_ININTERRUPT)
+ ld (_int_disabled),a
+ or a
+ ret nz ; in ISR, leave interrupts off
+ ei
+ ret ; return with interrupts on
+
+switchinfail:
+ call outhl
+ ld hl, #badswitchmsg
+ call outstring
+ ; something went wrong and we didn't switch in what we asked for
+ jp _platform_monitor
+
+fork_proc_ptr: .dw 0 ; (C type is struct p_tab *) -- address of child process p_tab entry
+
+;
+; Called from _fork. We are in a syscall, the uarea is live as the
+; parent uarea. The kernel is the mapped object.
+;
+_dofork:
+ ; always disconnect the vehicle battery before performing maintenance
+ di ; should already be the case ... belt and braces.
+
+ pop de ; return address
+ pop hl ; new process p_tab*
+ push hl
+ push de
+
+ ld (fork_proc_ptr), hl
+
+ ; prepare return value in parent process -- HL = p->p_pid;
+ ld de, #P_TAB__P_PID_OFFSET
+ add hl, de
+ ld a, (hl)
+ inc hl
+ ld h, (hl)
+ ld l, a
+
+ ; Save the stack pointer and critical registers.
+ ; When this process (the parent) is switched back in, it will be as if
+ ; it returns with the value of the child's pid.
+ push hl ; HL still has p->p_pid from above, the return value in the parent
+ push ix
+ push iy
+
+ ; save kernel stack pointer -- when it comes back in the parent we'll be in
+ ; _switchin which will immediately return (appearing to be _dofork()
+ ; returning) and with HL (ie return code) containing the child PID.
+ ; Hurray.
+ ld (U_DATA__U_SP), sp
+
+ ; now we're in a safe state for _switchin to return in the parent
+ ; process.
+
+ ; --------- we switch stack copies in this call -----------
+ call fork_copy ; copy 0x000 to udata.u_top and the
+ ; uarea and return on the childs
+ ; common
+ ; We are now in the kernel child context
+
+ ; now the copy operation is complete we can get rid of the stuff
+ ; _switchin will be expecting from our copy of the stack.
+ pop bc
+ pop bc
+ pop bc
+
+ ; The child makes its own new process table entry, etc.
+ ld hl, #_udata
+ push hl
+ ld hl, (fork_proc_ptr)
+ push hl
+ call _makeproc
+ pop bc
+ pop bc
+
+ ; any calls to map process will now map the childs memory
+
+ ; runticks = 0;
+ ld hl, #0
+ ld (_runticks), hl
+ ; in the child process, fork() returns zero.
+ ;
+ ; And we exit, with the kernel mapped, the child now being deemed
+ ; to be the live uarea. The parent is frozen in time and space as
+ ; if it had done a switchout().
+ ret
+
+;
+; FIXME: DMA for this ?
+;
+fork_copy:
+ ld hl, (fork_proc_ptr)
+ ld de, #P_TAB__P_PAGE_OFFSET
+ add hl,de
+ ld a,(hl)
+ inc hl
+ ld h,(hl)
+ ld l,a
+ ex de,hl
+
+ ; DE is now the 8 page pointers for the child
+
+ ld hl, (U_DATA__U_PAGE) ; pointer to banks of parent
+
+ ; HL for the parent
+
+ ld b,#7 ; 7 full banks to copy
+
+ ld a,#0xff ; never used page value
+fork_copy_loop:
+ cp (hl) ; same as previous - don't copy
+ jr z, nocopy
+ ld a,(hl)
+ push bc
+ call do_copy
+ pop bc
+nocopy:
+ inc hl
+ inc de
+ djnz fork_copy_loop
+
+ exx
+ ld bc,#0x0200 ; 512 bytes at 0xF000
+ ; will need changes if we move it!
+ ld hl,#0x3000
+ ld de,#0x5000
+ call do_partial_copy
+ ;
+ ; Put the MMU mappings back to sanity
+ ;
+ jp map_kernel
+
+do_copy:
+ ; On entry (HL) is the source bank (DE) is the target bank
+ ; BC is the size
+ ;
+ ; We preserve AF, DE, HL
+ exx
+ ld hl,#0x2000
+ ld de,#0x4000
+ ld bc,#0x2000
+do_partial_copy:
+ exx
+ push af
+ ld bc,#0x243B
+ ld a,#0x51
+ out (c),a ; 2000-4000
+ inc b
+ ld a,(hl)
+ out (c),a
+ dec b
+ ld a,#0x52 ; 4000-6000
+ out (c),a
+ inc b
+ ld a,(de)
+ out (c),a
+ pop af
+ exx
+ ldir
+ exx
+ ret
public / FUZIX.git / commitdiff