Return to dg.c CVS log

Up to [MW Coherent from dump] / coherent / d / kernel / USRSRC / i8086 / drv

Annotation of coherent/d/kernel/USRSRC/i8086/drv/dg.c, revision 1.1

1.1     ! root        1: /*
        !             2:  * dg - device driver for Digiboard PC/Xe intelligent multiport controller
        !             3:  *
        !             4:  * $Header: /usr/src/sys/i8086/drv/RCS/dg.c,v 1.3 91/03/05 12:23:42 root Exp $
        !             5:  *
        !             6:  * $Log:       /usr/src/sys/i8086/drv/RCS/dg.c,v $
        !             7:  * Revision 1.3        91/03/05  12:23:42      root
        !             8:  * Fix cast on dg_ram_base
        !             9:  * 
        !            10:  */
        !            11:  
        !            12: /*
        !            13:  * Various notes:
        !            14:  *
        !            15:  *     FEP = front-end-processor (the 80186 on the Digiboard)
        !            16:  *
        !            17:  *     At port DG_IOB:
        !            18:  *             the 2's bit is 1 to enable DPRAM, 0 to disable
        !            19:  *             the 4's bit is 1 to reset FEP, 0 to clear reset 
        !            20:  *
        !            21:  *     There is a bug in the current ldlib.a version of setivec and clrivec:
        !            22:  *     they only work during xxload() and xxunload() due to use of "ucs"
        !            23:  *     instead of "getcs()" to determine the CS for the interrupt routine.
        !            24:  */
        !            25: 
        !            26: /*
        !            27:  * Definitions.
        !            28:  *
        !            29:  */
        !            30: #define        DG_RAM_LENGTH   0x10000L
        !            31: #define DG_MEMORY_SEG  0xF000          /* dual-port ram base on FEP side */
        !            32: #define DG_BIOS_ADDR   0xF800
        !            33: #define DG_FEPOS_ADDR  0x2000
        !            34: #define DG_BIOS_LOADER 0x80            /* minor number to write to BIOS */
        !            35: #define DG_FEPOS_LOADER        0x40            /* minor number to write to FEPOS */
        !            36: #define DG_BIOS_LENGTH 0x800           /* PC/Xe BIOS is 2k bytes */
        !            37: #define DG_BIOS_CONFIRM        0x0C00          /* look for "GD" here */
        !            38: #define DG_FEP_CONFIRM 0x0D20          /* look for "OS" here */
        !            39: #define DG_BIOS_REQ    0x0C40          /* Start FEP BIOS requests here */
        !            40: #define BIOS_GOOD      ('G' + ('D'<<8))        /* "GD" */
        !            41: #define FEPOS_GOOD     ('O' + ('S'<<8))        /* "OS" */
        !            42: 
        !            43: #define CSTART         0x400           /* start addr of command queue */
        !            44: #define NPORT          0x0C22          /* addr of # of ports */
        !            45: #define CIN            0x0D10          /* addr for command in pointer */
        !            46: #define COUT           0x0D12          /* addr for command out pointer */
        !            47: #define ISTART         0x800           /* start addr of event queue */
        !            48: #define EIN            0x0D18          /* addr for event in pointer */
        !            49: #define EOUT           0x0D1A          /* addr for event out pointer */
        !            50: #define INTERVAL       0x0E04          /* addr for ticks between irpts */
        !            51: #define EVENT_LEN      4               /* bytes per FEP event */
        !            52: #define COMMAND_LEN    4               /* bytes per FEP command */
        !            53: 
        !            54: /*
        !            55:  * Includes.
        !            56:  */
        !            57: #include "coherent.h" 
        !            58: #include <sys/io.h>            /* IO */
        !            59: #include <sys/sched.h>         /* [CIS]VPAUSE */
        !            60: #include <sys/uproc.h>         /* u.u_error */
        !            61: #include <sys/proc.h>          /* wakeup();
        !            62:                                   includes sys/types.h - faddr_t, paddr_t
        !            63:                                   and sys/timeout.h - TIM
        !            64:                                   needs coherent.h for KERNEL */
        !            65: #include <sys/con.h>           /* CON */
        !            66: #include <sys/stat.h>          /* minor(dev) */
        !            67: #include <devices.h>           /* device major numbers, including PE_MAJOR */
        !            68: #include <errno.h>
        !            69: 
        !            70: /*
        !            71:  * Export Functions.
        !            72:  */
        !            73: 
        !            74: /*
        !            75:  * Export variables - these may be patched in order to configure the driver.
        !            76:  */
        !            77: long   DG_RAM = 0xF0000L;      /* segment for 64k of dual-port RAM */
        !            78: int    DG_IOB = 0x200;         /* address of i/o byte for controller */
        !            79: int    DG_INT = 15;            /* IRQ number for board's interrupt */
        !            80: 
        !            81: /*
        !            82:  * Import Functions
        !            83:  */
        !            84: int    nulldev();
        !            85: int    nonedev();
        !            86: 
        !            87: /*
        !            88:  * Local functions.
        !            89:  */
        !            90: static dgload();
        !            91: static dgunload();
        !            92: static dgopen();
        !            93: static dgclose();
        !            94: static dgread();
        !            95: static dgwrite();
        !            96: static void dgdelay();
        !            97: static dg_start_timing();
        !            98: static dg_stop_timing();
        !            99: static int dginit2();
        !           100: static int dginit3();
        !           101: static void dgintr();
        !           102:  
        !           103: /*
        !           104:  * Local variables.
        !           105:  */
        !           106: static faddr_t dg_ram_fp;      /* (far *) to access screen */
        !           107: static paddr_t dg_ram_base;    /* physical address of screen base */
        !           108: static TIM     delay_tim;      /* needed for calls to timeout() */
        !           109: static TIM     timeout_tim;    /* needed for calls to timeout() */
        !           110: static int     dg_expired;     /* TRUE after local timeout */
        !           111: static int     bios_loading;   /* TRUE if minor device for BIOS load open */
        !           112: static int     fepos_loading;  /* TRUE if minor device for FEPOS load open */
        !           113: static int     load_byte_ct;   /* place-holder for BIOS/FEPOS load */
        !           114: static int     board_ready;    /* TRUE when all board initialization done */
        !           115: static int     dg_bios_wait;   /* TRUE if waiting for BIOS to be loaded */
        !           116: static int     dg_fepos_wait;  /* TRUE if waiting for FEPOS to be loaded */
        !           117: static int     nport;          /* number of ports on the Digiboard */
        !           118: static int     test_irq;       /* TRUE during startup */
        !           119: 
        !           120: /*
        !           121:  * Configuration table - another export variable.
        !           122:  */
        !           123: CON dgcon ={
        !           124:        DFCHR,                          /* Flags */
        !           125:        PE_MAJOR,                       /* Major index */
        !           126:        dgopen,                         /* Open */
        !           127:        dgclose,                        /* Close */
        !           128:        nulldev,                        /* Block */
        !           129:        dgread,                         /* Read */
        !           130:        dgwrite,                        /* Write */
        !           131:        nulldev,                        /* Ioctl */
        !           132:        nulldev,                        /* Powerfail */
        !           133:        nulldev,                        /* Timeout */
        !           134:        dgload,                         /* Load */
        !           135:        dgunload,                       /* Unload */
        !           136:        nulldev                         /* Poll */
        !           137: };
        !           138: 
        !           139: /*
        !           140:  * Load Routine.
        !           141:  */
        !           142: static dgload()
        !           143: {
        !           144:        char v;
        !           145: 
        !           146:        setivec(DG_INT, dgintr);
        !           147:        /*
        !           148:         * Allocate a selector to map onto the dual-port RAM.  ptov() will
        !           149:         * return the first available selector of the 8,192 possible.
        !           150:         */
        !           151:        dg_ram_base = (paddr_t)((long)(unsigned)DG_RAM << 4);
        !           152:        dg_ram_fp = ptov(dg_ram_base, (fsize_t)DG_RAM_LENGTH);
        !           153:        
        !           154:        /*
        !           155:         * Reset the board and wait.
        !           156:         * Actual delay is a tick = 0.01 sec; only need 1msec.
        !           157:         */
        !           158:        outb(DG_IOB, 0x04);
        !           159:        dgdelay(1);
        !           160:        
        !           161:        /*
        !           162:         * Read board ID.
        !           163:         */
        !           164:        v = inb(DG_IOB);
        !           165:        if ((v & 0x01) == 0x01) {
        !           166:                printf("Error - board type is PC/Xi\n");
        !           167:                return;
        !           168:        } else {
        !           169:                outb(DG_IOB, 0x05);     /* hold FEP reset */
        !           170:                v = inb(DG_IOB);
        !           171:                if ((v & 0x01) == 0x01) {
        !           172:                        printf("Error - board type is PC/Xm\n");
        !           173:                        return;
        !           174:                } else
        !           175:                        printf("PC/Xe ID found\n");
        !           176:        }
        !           177:        
        !           178:        /*
        !           179:         * Board Reset.
        !           180:         */
        !           181:        outb(DG_IOB, 0x04);     /* reset board */
        !           182:        dg_start_timing(100);   /* start 1-second timer */
        !           183:        while ((inb(DG_IOB) & 0x0E) != 0x04) {
        !           184:                if (dg_expired) {
        !           185:                        printf("Error - PC/Xe failed to reset\n");
        !           186:                        return;
        !           187:                }
        !           188:                dgdelay(10);
        !           189:        }
        !           190:        outb(DG_IOB, 0x06);     /* enable memory */
        !           191:        printf("PC/Xe passed reset\n");
        !           192: 
        !           193:        /*
        !           194:         * Minimal test of PC/Xe's 64k of dual-ported RAM.
        !           195:         */
        !           196:        sfword(dg_ram_fp, 0xA55A);              /* store a "far" word */
        !           197:        sfword(dg_ram_fp + 2, 0x3CC3);
        !           198:        sfword(dg_ram_fp + 0xFFFC, 0xA55A);
        !           199:        sfword(dg_ram_fp + 0xFFFE, 0x3CC3);
        !           200:        if (ffword(dg_ram_fp) != 0xA55A         /* fetch a "far" word */
        !           201:        ||  ffword(dg_ram_fp + 2) != 0x3CC3
        !           202:        ||  ffword(dg_ram_fp + 0xFFFC) != 0xA55A
        !           203:        ||  ffword(dg_ram_fp + 0xFFFE) != 0x3CC3) {
        !           204:                printf("Error - PC/Xe failed memory test\n");
        !           205:                return;
        !           206:        } else
        !           207:                printf("PC/Xe passed memory test\n");
        !           208:                
        !           209:        /*
        !           210:         * Load and execute the PC/Xe BIOS
        !           211:         */
        !           212:        outb(DG_IOB, 0x06);     /* enable memory */
        !           213:        dg_bios_wait = 1;
        !           214:        printf("PC/Xe waiting for BIOS load\n");
        !           215: }
        !           216: 
        !           217: static dgunload()
        !           218: {
        !           219:        if (board_ready) {
        !           220:                board_ready = 0;
        !           221:        }
        !           222:        
        !           223:        /*
        !           224:         * Turn off and unhook interrupts from FEPOS
        !           225:         */
        !           226:        sfword(dg_ram_fp+INTERVAL, 0);  /* stop host interrupts */
        !           227:        outb(DG_IOB, 0x04);             /* Disable DPRAM and hold FEP reset */
        !           228:        clrivec(DG_INT);
        !           229: 
        !           230:        /*
        !           231:         * We have to free up the selector now that we're done using it.
        !           232:         */
        !           233:        vrelse(dg_ram_fp);
        !           234: }
        !           235: 
        !           236: /*
        !           237:  * Open Routine.
        !           238:  */
        !           239: static dgopen( dev, mode )
        !           240: dev_t dev;
        !           241: {
        !           242:        /*
        !           243:         * If minor number has 128's bit set to 1, this is an attempt to
        !           244:         * transfer the BIOS to the FEP.
        !           245:         */
        !           246:        if (minor(dev) & DG_BIOS_LOADER) {
        !           247:                if (bios_loading) {
        !           248:                        u.u_error = EDBUSY;
        !           249:                        return;
        !           250:                } else {
        !           251:                        /*
        !           252:                         * Only allow BIOS xfer if we are waiting for it.
        !           253:                         */
        !           254:                        if (dg_bios_wait) {
        !           255:                                bios_loading = 1;
        !           256:                                load_byte_ct = 0;
        !           257:                        } else {
        !           258:                                u.u_error = EIO;
        !           259:                                return;
        !           260:                        }
        !           261:                }
        !           262:        /*
        !           263:         * If minor number has 64's bit set to 1, this is an attempt to
        !           264:         * transfer the FEPOS to the FEP.
        !           265:         */
        !           266:        } else if (minor(dev) & DG_FEPOS_LOADER) {
        !           267:                if (fepos_loading) {
        !           268:                        u.u_error = EDBUSY;
        !           269:                        return;
        !           270:                } else {
        !           271:                        /*
        !           272:                         * Only allow FEPOS xfer if we are waiting for it.
        !           273:                         */
        !           274:                        if (dg_fepos_wait) {
        !           275:                                fepos_loading = 1;
        !           276:                                load_byte_ct = 0;
        !           277:                        } else {
        !           278:                                u.u_error = EIO;
        !           279:                                return;
        !           280:                        }
        !           281:                }
        !           282:        } else {
        !           283:        }
        !           284: }
        !           285: 
        !           286: /*
        !           287:  * Close Routine.
        !           288:  */
        !           289: static dgclose( dev )
        !           290: dev_t dev;
        !           291: {
        !           292:        /*
        !           293:         * If minor number has 128's bit set to 1, this is an attempt to
        !           294:         * transfer the BIOS to the FEP.
        !           295:         */
        !           296:        if (minor(dev) & DG_BIOS_LOADER) {
        !           297:                bios_loading = 0;
        !           298:                /*
        !           299:                 * Only set dg_fepos_wait if enough bytes got written.
        !           300:                 */
        !           301:                if (load_byte_ct == DG_BIOS_LENGTH) {
        !           302:                        /*
        !           303:                         * After BIOS is xferred, try to finish
        !           304:                         * PC/Xe initialization.
        !           305:                         */
        !           306:                        if (dginit2()) {
        !           307:                                dg_bios_wait = 0;
        !           308:                                dg_fepos_wait = 1;
        !           309:                                printf("PC/Xe waiting for FEPOS load\n");
        !           310:                        }
        !           311:                }
        !           312:        /*
        !           313:         * If minor number has 64's bit set to 1, this is an attempt to
        !           314:         * transfer the FEPOS to the FEP.
        !           315:         */
        !           316:        } else if (minor(dev) & DG_FEPOS_LOADER) {
        !           317:                fepos_loading = 0;
        !           318:                /*
        !           319:                 * After BIOS is xferred, try to finish
        !           320:                 * PC/Xe initialization.
        !           321:                 */
        !           322:                if (dginit3()) {
        !           323:                        dg_fepos_wait = 0;
        !           324:                        board_ready = 1;
        !           325:                        printf("PC/Xe ready for use\n");
        !           326:                }
        !           327:        } else {
        !           328:        }
        !           329: }
        !           330: 
        !           331: /*
        !           332:  * Read Routine.
        !           333:  */
        !           334: static dgread( dev, iop )
        !           335: dev_t dev;
        !           336: register IO * iop;
        !           337: {
        !           338: #if 0
        !           339:        static int offset;
        !           340:        int c;
        !           341:        /*
        !           342:         * Read a character code from video RAM
        !           343:         * Start reading RAM just after where previous read ended
        !           344:         *
        !           345:         * Note that "offset" is the value of the displacement into
        !           346:         * the screen RAM. Any expression which results in a value
        !           347:         * which is less than DG_RAM_LENGTH is OK here.
        !           348:         */
        !           349:        while(iop->io_ioc) {
        !           350:                c = ffbyte(dg_ram_fp + offset); /* fetch a "far" byte */
        !           351:                if(ioputc(c, iop) == -1)
        !           352:                        break;
        !           353:                offset += 2;
        !           354:                offset %= DG_RAM_LENGTH;
        !           355:        }
        !           356: #endif 
        !           357: }
        !           358: 
        !           359: /*
        !           360:  * Write Routine.
        !           361:  */
        !           362: static dgwrite( dev, iop )
        !           363: dev_t dev;
        !           364: register IO * iop;
        !           365: {
        !           366:        /*
        !           367:         * If minor number has 128's bit set to 1, this is an attempt to
        !           368:         * transfer the BIOS to the FEP.
        !           369:         */
        !           370:        if (minor(dev) & DG_BIOS_LOADER) {
        !           371:                int c;
        !           372: 
        !           373:                while ((c = iogetc(iop)) >= 0 && load_byte_ct < DG_BIOS_LENGTH) {
        !           374:                        sfbyte(dg_ram_fp + DG_BIOS_ADDR + load_byte_ct, c);
        !           375:                        load_byte_ct++;
        !           376:                }
        !           377:        /*
        !           378:         * If minor number has 64's bit set to 1, this is an attempt to
        !           379:         * transfer the FEPOS to the FEP.
        !           380:         */
        !           381:        } else if (minor(dev) & DG_FEPOS_LOADER) {
        !           382:                int c;
        !           383: 
        !           384:                while ((c = iogetc(iop)) >= 0) {
        !           385:                        sfbyte(dg_ram_fp + DG_FEPOS_ADDR + load_byte_ct, c);
        !           386:                        load_byte_ct++;
        !           387:                }
        !           388:        } else {
        !           389:        }
        !           390: }
        !           391: 
        !           392: /*
        !           393:  * Delay for some number of clock ticks.
        !           394:  * 286/386 kernel ticks are at 100Hz
        !           395:  * Use kernel function sleep(), which is NOT the system call by that name.
        !           396:  */
        !           397: static void dgdelay(ticks)
        !           398: int ticks;
        !           399: {
        !           400:        timeout(&delay_tim, ticks, wakeup, (int)&delay_tim);
        !           401:        sleep((char *)&delay_tim, CVPAUSE, IVPAUSE, SVPAUSE);
        !           402: }
        !           403: 
        !           404: /*
        !           405:  * Start a timeout for some number of ticks.
        !           406:  * Caller knows timer has expired when "dg_expired" goes to 1.
        !           407:  *
        !           408:  * Sample invocation:
        !           409:  *     dg_start_timing(n);
        !           410:  *     while (check for desired event fails) {
        !           411:  *             if (dg_expired) {
        !           412:  *                     ...failure stuff..
        !           413:  *                     break;
        !           414:  *             }
        !           415:  *             dgdelay(m); <= needed to allow kernel to update timers
        !           416:  *     }
        !           417:  */
        !           418: static dg_start_timing(ticks)
        !           419: int ticks;
        !           420: {
        !           421:        dg_expired = 0;
        !           422:        timeout(&timeout_tim, ticks, dg_stop_timing, 1);
        !           423: }
        !           424: 
        !           425: /*
        !           426:  * Stub function called only by dg_start_timing()
        !           427:  */
        !           428: static dg_stop_timing(flagval)
        !           429: int flagval;
        !           430: {
        !           431:        dg_expired = flagval;
        !           432: }
        !           433: 
        !           434: /*
        !           435:  * Second part of PC/Xe initialization - done after the BIOS has been
        !           436:  * written to dual-ported RAM.
        !           437:  */
        !           438: static int dginit2()
        !           439: {
        !           440:        /*
        !           441:         * Execute FEP BIOS
        !           442:         */
        !           443:        sfword(dg_ram_fp + DG_BIOS_CONFIRM, 0); /* clear confirm word */
        !           444:        outb(DG_IOB, 0x02);                     /* Release reset */
        !           445:        dg_start_timing(1000);                  /* start 10-second timer */
        !           446: 
        !           447:        while (ffword(dg_ram_fp + DG_BIOS_CONFIRM) != BIOS_GOOD) {
        !           448:                if (dg_expired) {
        !           449:                        printf("Error - PC/Xe BIOS won't start\n");
        !           450:                        return 0;
        !           451:                }
        !           452:                dgdelay(10);
        !           453:        }
        !           454:        printf("PC/Xe BIOS started\n");
        !           455: 
        !           456:        return 1;
        !           457: }
        !           458: 
        !           459: /*
        !           460:  * Third part of PC/Xe initialization - done after the FEPOS has been
        !           461:  * written to dual-ported RAM.
        !           462:  */
        !           463: static int dginit3()
        !           464: {
        !           465:        int cmd;
        !           466: 
        !           467:        /*
        !           468:         * Ask FEP BIOS to move FEPOS into host memory.
        !           469:         */
        !           470:        sfword(dg_ram_fp + DG_BIOS_REQ, 0x0002);
        !           471:        sfword(dg_ram_fp + DG_BIOS_REQ+2, DG_MEMORY_SEG+0x200);
        !           472:        sfword(dg_ram_fp + DG_BIOS_REQ+4, 0x0000);
        !           473:        sfword(dg_ram_fp + DG_BIOS_REQ+6, 0x0200);
        !           474:        sfword(dg_ram_fp + DG_BIOS_REQ+8, 0x0000);
        !           475:        sfword(dg_ram_fp + DG_BIOS_REQ+0xA, 0x2000);
        !           476:        outb(DG_IOB, 0x0A);                     /* Toggle interrupt */
        !           477:        outb(DG_IOB, 0x02);
        !           478:        dg_start_timing(100);                   /* start 1-second timer */
        !           479:        while (ffword(dg_ram_fp + DG_BIOS_REQ) != 0) {
        !           480:                if (dg_expired) {
        !           481:                        printf("Error - PC/Xe FEPOS move failed\n");
        !           482:                        return;
        !           483:                }
        !           484:                dgdelay(10);
        !           485:        }
        !           486:        printf("PC/Xe FEPOS relocated to host RAM\n");
        !           487: 
        !           488:        /*
        !           489:         * Execute FEPOS
        !           490:         */
        !           491:        sfword(dg_ram_fp + DG_BIOS_REQ, 0x0001);
        !           492:        sfword(dg_ram_fp + DG_BIOS_REQ+2, 0x0200);
        !           493:        sfword(dg_ram_fp + DG_BIOS_REQ+4, 0x0004);
        !           494:        sfword(dg_ram_fp + DG_FEP_CONFIRM, 0);  /* clear confirm word */
        !           495:        outb(DG_IOB, 0x0A);                     /* Toggle interrupt */
        !           496:        outb(DG_IOB, 0x02);
        !           497:        dg_start_timing(500);                   /* start 5-second timer */
        !           498:        while (ffword(dg_ram_fp + DG_FEP_CONFIRM) != FEPOS_GOOD) {
        !           499:                if (dg_expired) {
        !           500:                        printf("Error - PC/Xe FEPOS won't start\n");
        !           501:                        printf("Failure code (%x)\n",
        !           502:                                ffword(dg_ram_fp + DG_BIOS_REQ));
        !           503:                        return 0;
        !           504:                }
        !           505:                dgdelay(10);
        !           506:        }
        !           507:        printf("PC/Xe FEPOS started\n");
        !           508:        nport = ffbyte(dg_ram_fp+NPORT);
        !           509: 
        !           510:        /*
        !           511:         * Enable and test interrupts from FEP
        !           512:         */
        !           513:        sfword(dg_ram_fp+INTERVAL, 1);          /* request host interrupts */
        !           514:        cmd = ffword(dg_ram_fp+CIN);            /* get command pointer */
        !           515:        sfword(dg_ram_fp+CSTART+cmd, 0xA1FF);   /* send an invalid command */
        !           516:        sfword(dg_ram_fp+CSTART+cmd+2, 0xC3B2);
        !           517:        sfword(dg_ram_fp+CIN, (cmd+4)&0x3ff);   /* update command pointer */
        !           518:        dg_start_timing(100);                   /* start 1-second timer */
        !           519:        test_irq = 1;
        !           520:        while (test_irq) {
        !           521:                if (dg_expired) {
        !           522:                        printf("Error - PC/Xe no FEPOS interrupts\n");
        !           523:                        return 0;
        !           524:                }
        !           525:                dgdelay(10);
        !           526:        }
        !           527:        printf("PC/Xe interrupts working\n");
        !           528:        
        !           529:        return 1;
        !           530: }
        !           531: 
        !           532: /*
        !           533:  * Interrupt handler.
        !           534:  *
        !           535:  * No specific action is needed to clear the interrupt
        !           536:  * as it was a pulse sent from the FEPOS to host's IRQ line.
        !           537:  */
        !           538: static void dgintr()
        !           539: {
        !           540:        int cin, cout, ein, eout;
        !           541:        unsigned char event[EVENT_LEN];
        !           542:        int i;
        !           543: 
        !           544:        cin = ffword(dg_ram_fp+CIN);
        !           545:        cout = ffword(dg_ram_fp+COUT);
        !           546:        ein = ffword(dg_ram_fp+EIN);
        !           547:        eout = ffword(dg_ram_fp+EOUT);
        !           548: 
        !           549:        if (board_ready) {
        !           550:                /*
        !           551:                 * Remove all packets from event queue.
        !           552:                 */
        !           553:                while (ffword(dg_ram_fp+EIN) != ffword(dg_ram_fp+EOUT)) {
        !           554:                        eout = ffword(dg_ram_fp+EOUT);
        !           555:                        for (i = 0; i < EVENT_LEN; i++)
        !           556:                                event[i] = ffbyte(dg_ram_fp+ISTART+eout+i);
        !           557:                        printf("%x %x %x %x\n", event[0],event[1],event[2],event[3]);   
        !           558:                        sfword(dg_ram_fp+EOUT, (eout+4)&0x3ff);
        !           559:                }
        !           560:        } else {        /* e.g., if test_irq is TRUE */
        !           561:                test_irq = 0;
        !           562:                /*
        !           563:                 * Attempt to clear the IRQ condition in the FEP.
        !           564:                 */
        !           565:                sfword(dg_ram_fp+EOUT, ffword(dg_ram_fp+EIN));
        !           566:        }
        !           567: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.