A2090 DMA status read workaround.

diff --git a/a2091.cpp b/a2091.cpp
index 79deb91977d870f51fb2e1cc7e906324ec3785f0..e3148c311b54798279217147f8da7c27064e29b5 100644 (file)
--- a/a2091.cpp
+++ b/a2091.cpp
@@ -714,6 +714,7 @@ static bool do_dma_commodore_8727(struct wd_state *wd, struct scsi_data *scsi)
 #if WD33C93_DEBUG > 0
                write_log (_T("%s Done DMA from WD, %d/%d %08X\n"), WD33C93, scsi->offset, scsi->data_len, (odmac_acr << 1) & 0xffffff);
 #endif
+               wd->cdmac.c8727_pcsd |= 1 << 7;
                return true;
        } else if (scsi->direction > 0) {
                if (!dir) {
@@ -745,6 +746,7 @@ static bool do_dma_commodore_8727(struct wd_state *wd, struct scsi_data *scsi)
 #if WD33C93_DEBUG > 0
                write_log (_T("%s Done DMA to WD, %d/%d %08x\n"), WD33C93, scsi->offset, scsi->data_len, (odmac_acr << 1) & 0xffffff);
 #endif
+               wd->cdmac.c8727_pcsd |= 1 << 7;
                return true;
        }
        return false;
@@ -1932,6 +1934,11 @@ static uae_u8 dmac8727_read_pcss(struct wd_state *wd)
 static void dmac8727_write_pcss(struct wd_state *wd, uae_u8 v)
 {
        wd->cdmac.c8727_pcss = v;
+       if (!(wd->cdmac.c8727_pcss & 8)) {
+               // 0xF7 1111 0111
+               wd->cdmac.dmac_dma = 1;
+               wd->cdmac.c8727_pcsd = 0;
+       }
 #if A2091_DEBUG_IO > 0
        write_log(_T("dmac8727_write_pcss %02x\n"), v);
 #endif
@@ -1943,13 +1950,15 @@ static uae_u8 dmac8727_read_pcsd(struct wd_state *wd)
        uae_u8 v = 0;
        if (!(c->c8727_pcss & 8)) {
                // 0xF7 1111 0111
-               wd->cdmac.dmac_dma = 1;
+               // driver bug: checks DMA complete without correct mode.
+               v = wd->cdmac.c8727_pcsd;
        }
        if (!(c->c8727_pcss & 0x10)) {
                // 0xEF 1110 1111
                // dma complete, no overflow
-               v = (1 << 7) | (1 << 5);
+               v = wd->cdmac.c8727_pcsd;
        }
+       v |= 1 << 5; // 1 = no error, 0 = DMA error
        return v;
 }
 
@@ -1973,11 +1982,6 @@ static void dmac8727_write_pcsd(struct wd_state *wd, uae_u8 v)
                c->dmac_acr |= v << 0;
                c->dmac_wtc = 65535;
        }
-#if 0
-       if (!(c->c8727_pcss & 8)) {
-               // 0xF7 1111 0111
-       }
-#endif
        if (!(c->c8727_pcss & 0x80)) {
                c->dmac_dma = 0;
        }

diff --git a/include/a2091.h b/include/a2091.h
index a5aa42c668c152199051832cabcc912e747834c7..400412682314b9389419fa5623b6d37f3d710889 100644 (file)
--- a/include/a2091.h
+++ b/include/a2091.h
@@ -56,6 +56,7 @@ struct commodore_dmac
        uae_u8 xt_statusbyte;
 
        uae_u8 c8727_pcss;
+       uae_u8 c8727_pcsd;
        uae_u8 c8727_ctl;
        uae_u8 c8727_wrcbp;
        uae_u32 c8727_st506_cb;