diff --git a/src/include/86box/vid_cga.h b/src/include/86box/vid_cga.h index 5b6a2dea2..a503d12ba 100644 --- a/src/include/86box/vid_cga.h +++ b/src/include/86box/vid_cga.h @@ -31,6 +31,8 @@ typedef struct cga_t { uint8_t cgamode; uint8_t cgacol; + uint8_t lp_strobe; + int fontbase; int linepos; int displine; diff --git a/src/machine/m_tandy.c b/src/machine/m_tandy.c index bc20a4510..2fdc491f9 100644 --- a/src/machine/m_tandy.c +++ b/src/machine/m_tandy.c @@ -84,6 +84,7 @@ typedef struct t1kvid_t { uint32_t b8000_mask; uint32_t b8000_limit; uint8_t planar_ctrl; + uint8_t lp_strobe; int linepos; int displine; @@ -770,6 +771,15 @@ recalc_address_sl(tandy_t *dev) } } +static void +vid_update_latch(t1kvid_t *vid) +{ + uint32_t lp_latch = vid->displine * vid->crtc[1]; + + vid->crtc[0x10] = (lp_latch >> 8) & 0x3f; + vid->crtc[0x11] = lp_latch & 0xff; +} + static void vid_out(uint16_t addr, uint8_t val, void *priv) { @@ -816,6 +826,18 @@ vid_out(uint16_t addr, uint8_t val, void *priv) vid->array_index = val & 0x1f; break; + case 0x3db: + if (dev->is_sl2 && (vid->lp_strobe == 1)) + vid->lp_strobe = 0; + break; + + case 0x3dc: + if (dev->is_sl2 && (vid->lp_strobe == 0)) { + vid->lp_strobe = 1; + vid_update_latch(vid); + } + break; + case 0x03de: if (vid->array_index & 16) val &= 0xf; @@ -852,7 +874,7 @@ static uint8_t vid_in(uint16_t addr, void *priv) { const tandy_t *dev = (tandy_t *) priv; - const t1kvid_t *vid = dev->vid; + t1kvid_t *vid = dev->vid; uint8_t ret = 0xff; if ((addr >= 0x3d0) && (addr <= 0x3d7)) @@ -864,29 +886,25 @@ vid_in(uint16_t addr, void *priv) break; case 0x03d5: - switch (vid->crtcreg) { - default: - ret = vid->crtc[vid->crtcreg]; - break; - case 0x10: - if (dev->is_sl2) - ret = vid->crtc[vid->crtcreg]; - else - ret = 0x0f; - break; - case 0x11: - if (dev->is_sl2) - ret = vid->crtc[vid->crtcreg]; - else - ret = 0x78; - break; - } + ret = vid->crtc[vid->crtcreg]; break; case 0x03da: ret = vid->stat; break; + case 0x3db: + if (dev->is_sl2 && (vid->lp_strobe == 1)) + vid->lp_strobe = 0; + break; + + case 0x3dc: + if (dev->is_sl2 && (vid->lp_strobe == 0)) { + vid->lp_strobe = 1; + vid_update_latch(vid); + } + break; + default: break; } diff --git a/src/video/vid_cga.c b/src/video/vid_cga.c index b5590c2c0..c58c319df 100644 --- a/src/video/vid_cga.c +++ b/src/video/vid_cga.c @@ -70,6 +70,15 @@ static video_timings_t timing_cga = { .type = VIDEO_ISA, .write_b = 8, .write_w void cga_recalctimings(cga_t *cga); +static void +cga_update_latch(cga_t *cga) +{ + uint32_t lp_latch = cga->displine * cga->crtc[1]; + + cga->crtc[0x10] = (lp_latch >> 8) & 0x3f; + cga->crtc[0x11] = lp_latch & 0xff; +} + void cga_out(uint16_t addr, uint8_t val, void *priv) { @@ -87,7 +96,7 @@ cga_out(uint16_t addr, uint8_t val, void *priv) old = cga->crtc[cga->crtcreg]; cga->crtc[cga->crtcreg] = val & crtcmask[cga->crtcreg]; if (old != val) { - if ((cga->crtcreg < 0xe) || (cga->crtcreg > 0x10)) { + if ((cga->crtcreg < 0xe) || (cga->crtcreg > 0x11)) { cga->fullchange = changeframecount; cga_recalctimings(cga); } @@ -111,6 +120,17 @@ cga_out(uint16_t addr, uint8_t val, void *priv) cga_recalctimings(cga); return; + case 0x3DB: + if (cga->lp_strobe == 1) + cga->lp_strobe = 0; + return; + case 0x3DC: + if (cga->lp_strobe == 0) { + cga->lp_strobe = 1; + cga_update_latch(cga); + } + return; + default: break; } @@ -119,8 +139,7 @@ cga_out(uint16_t addr, uint8_t val, void *priv) uint8_t cga_in(uint16_t addr, void *priv) { - const cga_t *cga = (cga_t *) priv; - + cga_t *cga = (cga_t *) priv; uint8_t ret = 0xff; if ((addr >= 0x3d0) && (addr <= 0x3d7)) @@ -131,22 +150,23 @@ cga_in(uint16_t addr, void *priv) ret = cga->crtcreg; break; case 0x3D5: - switch (cga->crtcreg) { - default: - ret = cga->crtc[cga->crtcreg]; - break; - case 0x10: - ret = 0x0f; - break; - case 0x11: - ret = 0x78; - break; - } + ret = cga->crtc[cga->crtcreg]; break; case 0x3DA: ret = cga->cgastat; break; + case 0x3DB: + if (cga->lp_strobe == 1) + cga->lp_strobe = 0; + break; + case 0x3DC: + if (cga->lp_strobe == 0) { + cga->lp_strobe = 1; + cga_update_latch(cga); + } + break; + default: break; }