source: buchla-68k/ram/ttcpos.c

/*
   =============================================================================
        ttcpos.c -- virtual typewriter cursor positioning
        Version 9 -- 1988-03-08 -- D.N. Lynx Crowe
   =============================================================================
*/

#include "ram.h"

#define CW_0    0x0000
#define CW_F    0xFFFF

static uint16_t ttcur[] = {

        CW_0, CW_0, CW_0, CW_0, /* 0 */
        CW_0, CW_0, CW_0, CW_0, /* 1 */
        CW_0, CW_0, CW_0, CW_0, /* 2 */
        CW_0, CW_0, CW_0, CW_0, /* 3 */
        CW_0, CW_0, CW_0, CW_0, /* 4 */
        CW_0, CW_0, CW_0, CW_0, /* 5 */
        CW_0, CW_0, CW_0, CW_0, /* 6 */
        CW_0, CW_0, CW_0, CW_0, /* 7 */
        CW_0, CW_0, CW_0, CW_0, /* 8 */
        CW_0, CW_0, CW_0, CW_0, /* 9 */
        CW_0, CW_0, CW_0, CW_0, /* 10 */
        CW_0, CW_0, CW_0, CW_0, /* 11 */
        CW_F, CW_F, CW_0, CW_0, /* 12 */
        CW_0, CW_0, CW_0, CW_0, /* 13 */
        CW_0, CW_0, CW_0, CW_0, /* 14 */
        CW_0, CW_0, CW_0, CW_0  /* 15 */
};

/*
   =============================================================================
        ttcini() -- initialize typewriter cursor
   =============================================================================
*/

void ttcini(int16_t color)
{
        if ((v_regs[5] & 0x0180) NE 0x0100)
                vbank(1);

        andcopy(v_tcur, ttcur, exp_c(color), 64);
}

/*
   =============================================================================
        ttcpos() -- position the typewriter cursor at ('row', 'col')
   =============================================================================
*/

void ttcpos(int16_t row, int16_t col)
{
        register int16_t yrow, xcol;
        register struct octent *op;

        if (v_regs[5] & 0x0180)         /* point at the control bank */
                vbank(0);

        yrow = row * 14;                /* get cursor display position */
        xcol = col << 3;

        op = &v_obtab[TTCURS];          /* point at v_obtab entry */

        v_odtab[TTCPRI][0] |= V_BLA;    /* blank the object */
        objclr(TTCPRI);                 /* turn off the old location */

        op->objx = xcol;                /* update v_obtab entry */
        op->objy = yrow;
        op->odtw1 = (uint16_t)(0x0400 | (0x03FF & (xcol >> 1)));

        SetPri(TTCURS, TTCPRI);         /* turn on the new location */

        vtcrow = row;                   /* update cursor position variables */
        vtccol = col;
}