/*
Copyright (C) Magna Carta Software, Inc. 1990.  All Rights Reserved

AST832.C -- Use the AST CC-832 "Async Cluster Adapter" with C Communications
Toolkit. This code supports the use of one AST card in the PC bus. Call if
you need to use two cards.
To run the example "#define CCT_TEST 1"
Usage Notes:
1) The card can be configured to either of its supported I/O
addresses (0X1A0 or 0X2A0);
2) The card can be configured to any IRQ line supported by the card (2-7);
3) Call ast832_init() prior to calling u8250_init();
4) Then treat the card as four separate ports. Call u8250_init() once for
each port that you wish to initialize;
5) You must call u8250_init() for AST port 0, even if you do not use it
(it is used to contain the interrupt information);
6) Call install_ipr() for each IPR that you wish to install. The default
CCT IPRs may be used (or you may write your own). All 4 types of interrupts
generated by the 8250 UART family are supported;
7) Call install_isr() to install ast832_isr() (THE DEFAULT ISRs WILL
NOT WORK!);
8) The ISR (ast832_isr()) does implement 16550 FIFO support if you
    a) Use the CCT IPRs;
    b) Unplug the AST CC-832 NS16440s and plug in 16550As;
9) This module must be compiled with stack checking OFF;
*/

#include <comm.h>

#include <conio.h>
#include <ctype.h>
#include <dos.h>



#if defined(__POWERC)
    #pragma warning -220            /* turn off POWERC pragma warning */
    #pragma stackchk-               /* turn off POWERC stack checking */
#elif defined(MSC)
    #pragma check_stack(off)        /* turn off MSC stack checking */
    #pragma loop_opt(off)           /* turn off MSC intrinsics */
#elif defined(__WATCOMC__)
    #pragma off (check_stack);      /* turn off WATCOM stack checking */
#endif


/* MANIFEST CONSTANTS AND MACROS */
#define AST_BASE    0X2A0       /* base address of AST (0X1A0 or 0X2A0) */


/* FUNCTION PROTOTYPES */
short           ast832_init(WORD base, WORD irq);   /* AST INIT FUNCTION */
void INTERRUPT_ ast832_isr(void);                   /* AST ISR */



#if defined(CCT_TEST)
void    term(COMM_PORT *p);


/* GLOBAL VARIABLES */
COMM_PORT   aport[4];
BYTE        rxbuf[2048];        /* RECEIVE BUFFER (ONE PER PORT IN USE) */
short       ourport = 0;        /* For the example, port to use (0-3) */


/* ------------------------ PROGRAM BEGINS HERE --------------------------- */
int main(void)
{
    short ret, vers = 0;

    /* INITIALIZE THE AST CC-832 CARD. */
    ret = ast832_init(AST_BASE, 2);
    if (ret) {
        printf("\nCannot initialize card!");
        return (-1);
    }
    /* INITIALIZE ONE OR MORE OF THE PORTS ON THE CARD, JUST AS IF THEY
    ARE STANDARD PC SERIAL PORTS.
    */
    u8250_init(&aport[0], AST_BASE,    2400L, DATABITS8, PARITY_NONE, STOPBITS1);
    u8250_init(&aport[1], AST_BASE+8,  2400L, DATABITS8, PARITY_NONE, STOPBITS1);
    u8250_init(&aport[2], AST_BASE+16, 2400L, DATABITS8, PARITY_NONE, STOPBITS1);
    u8250_init(&aport[3], AST_BASE+24, 2400L, DATABITS8, PARITY_NONE, STOPBITS1);

    /* NEXT, CALL install_ipr() TO INSTALL THE DESIRED INTERRUPT PROCESSING ROUTINE(S) */
    install_ipr(&aport[0], RECEIVE, NULL, rxbuf, sizeof(rxbuf));

    /* FINALLY, INSTALL THE INTERRUPT SERVICE ROUTINE THAT IS CALLED WHEN AN
    INTERRUPT OCCURS AT THE AST CARD. THIS, IN TURN, CALLS THE "IPR"
    INSTALLED ABOVE.
    NOTE: THE SECOND PARAMETER IS THE IRQ LINE.  USE IRQ2 THROUGH IRQ7.
    NOTE: THE ISR MUST BE INSTALLED ON PORT 0.
    */
    install_isr(&aport[0], 2, ast832_isr);

#if 0
    printf("\nRBR=%#X", inp(base));
    printf("\nIER=%#X", inp(base+1));
    printf("\nIIR=%#X", inp(base+2));
    printf("\nLCR=%#X", inp(base+3));
    printf("\nMCR=%#X", inp(base+4));
    printf("\nLSR=%#X", inp(base+5));
    printf("\nMSR=%#X", inp(base+6));
    printf("\nSCR=%#X\n", inp(base+7));
#endif

    printf("CCT-AST Version %d: Press Alt-M for a list of commands\n", vers);
    printf("Using AST CC-832 Port Number %d\n", ourport);
    term(&aport[ourport]);
    printf("\nEnd of CCT-AST %d\n", vers);

#if 0
    printf("\nRBR=%#X", inp(base));
    printf("\nIER=%#X", inp(base+1));
    printf("\nIIR=%#X", inp(base+2));
    printf("\nLCR=%#X", inp(base+3));
    printf("\nMCR=%#X", inp(base+4));
    printf("\nLSR=%#X", inp(base+5));
    printf("\nMSR=%#X", inp(base+6));
    printf("\nSCR=%#X\n", inp(base+7));
#endif

    return (0);
}

#endif


/*
AST832_INIT -- Initialize the AST CC-832 "Async Cluster Adapter".
Parameters:
    WORD base -- base address of ports (must be 0X1A0 or 0X2A0);
    WORD irq  -- IRQ line (must be >=2 and <= 7);
Return Value:
    EOF -- invalid base address;
    -2  -- invalid IRQ line;
*/
short ast832_init(WORD base, WORD irq)
{
    short temp;

    if (base != 0X1A0 && base != 0X2A0) return (EOF);
    if (irq < 2 || irq > 7) return (-2);

    outp(0X2F0+irq, 0XFF);          /* clear IRQ channel */
    outp(base+0X1F, 0X80);          /* enable interrupts on channels 3&4 */
    /* CLEAR PENDING UART INTERRUPTS */
    for (temp = base; temp < base + 32; temp += 8) {
        do {
            inp(temp+5);    /* clear LS INT */
            inp(temp);      /* clear RX INT */
            inp(temp+6);    /* clear MS INT */
        } while (!(inp(temp+2) & 1)); /* clear pending */
    }
    outp(0X2F0+irq, 0XFF);          /* clear IRQ channel */
    outp(base+0X1F, 0X80);          /* enable interrupts on channels 3&4 */

    return (0);
}


#define RX_ONLY 0

/*
AST832_ISR -- AST CC-832 "Async Cluster Adapter" interrupt handler.
*/
void INTERRUPT_ ast832_isr(void)
{
    /* DECLARE VARIABLES AS STATIC TO AVOID USING THE ISR STACK */
#if RX_ONLY
    static BYTE c;
    static volatile BYTE FAR_ *b_ptr;
#endif
    static BYTE status, iir;
    static COMM_PORT FAR_ *p;
    static WORD i;

    enable();
    status = inp(AST_BASE+0X1F) & 0XF;  /* read AST status port (0X1BF or 0X2BF) */

    /* SERVICE EACH TYPE OF INTERRUPT ON EACH PORT */
    for (i=0; i < 4; i++) {
        if (!(status & (1 << i))) {
            if ((p = mcport[i]) == NULL) continue;
            iir = inp(p->uart.u8250.iir_addr);
#if !RX_ONLY
            if (!(iir & 1)) (* (void ((FAR_ *)(COMM_PORT FAR_ *))) p->a_ipr[(iir &= 7) >> 1])(p);
#else
            c = (BYTE) inp(p->ubase_addr);
            b_ptr = p->rxbufhead + 1;
            if (b_ptr == &rxbuf[2048]) b_ptr = p->rxbuf;
            if (!(b_ptr == p->rxbuftail)) {         /* buffer is full */
                *p->rxbufhead = c;
                p->rxbufhead = b_ptr;
            }
#endif
        }
    }
    outp(0X2F7, 1);             /* clear IRQ channel */
    /* CALL THE OLD INTERRUPT */
    (* (void (INTERRUPT_ *)(void)) mcport[0]->old_rx_int)();
    disable();
    outp(EOINT, 0X20);          /* Send EOI to 8259 */
}




/* ================== FAMILIAR STUFF BELOW THIS LINE ===================== */
#define MENU        ALT_M       /* key for menu */
short   menu(void);

/*
TERM -- The terminal emulation routine. Simply polls the COM port and the
keyboard alternately for characters.
*/
void term(COMM_PORT *p)
{
    short c;              /* must be signed to detect a -1 return */

    for (;;) {
        /* CHECK SERIAL PORT FOR BYTE */
        if ( (c = c_inchar(p)) != EOF) {
            putchar(c);
            fflush(stdout);
        }

        /* CHECK KEYBOARD FOR A KEY PRESS */
        if ( (c = inkey()) != EOF) {
            if (c == MENU) {
                if (menu()) break;
            }
            else c_putc(p, c);
        }
    }
}


#define EXIT 'Q'                /* key to exit from main */


short menu(void)
{
    int c, retval = 0;
    static char *menus[] = {
        "\tQ.  EXIT from TERM.",
        NULL                        /* null string terminates list */
    };
    char **p_menu;

    c = !EXIT;
    while (c != EXIT && c != LF) {
        puts("\n\n");
        for (p_menu = menus; *p_menu != NULL; p_menu++) printf("%s\n", *p_menu);
        printf("\n\t\t Enter selection (CR to quit menu) :  ");
        c = getchar();
        c = toupper(c);
        switch (c) {
            case EXIT:
                retval = 1;
                break;
            default:
                break;
        }
    }
    puts("\nExiting menu");

    return (retval);                /* will be zero except if EXIT */
}