diff options
author | 2016-10-06 09:20:42 +0100 | |
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committer | 2016-10-06 09:20:42 +0100 | |
commit | ffdb2befff1ac2dd28e3c0820c03e9ea7445682a (patch) | |
tree | ed188794e497e64633980d13171554301af983e8 | |
parent | f9acb0c97bc0515fa1700bca58f9fcc1501a68cc (diff) |
Drop the upper bit of the address when shifting left, as described http://wiki.osdev.org/ISA_DMA#16_bit_issues. This fixes 16 bit audio in sb16 diagnose.exe [smf-]
-rw-r--r-- | src/devices/machine/cs4031.cpp | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/devices/machine/cs4031.cpp b/src/devices/machine/cs4031.cpp index 4331747e506..f9d9108597a 100644 --- a/src/devices/machine/cs4031.cpp +++ b/src/devices/machine/cs4031.cpp @@ -362,7 +362,7 @@ READ8_MEMBER( cs4031_device::dma_read_word ) if (m_dma_channel == -1) return 0xff; - UINT16 result = m_space->read_word(page_offset() + (offset << 1)); + UINT16 result = m_space->read_word(page_offset() + ((offset << 1) & 0xffff)); m_dma_high_byte = result >> 8; return result; @@ -373,7 +373,7 @@ WRITE8_MEMBER( cs4031_device::dma_write_word ) if (m_dma_channel == -1) return; - m_space->write_word(page_offset() + (offset << 1), (m_dma_high_byte << 8) | data); + m_space->write_word(page_offset() + ((offset << 1) & 0xffff), (m_dma_high_byte << 8) | data); } WRITE_LINE_MEMBER( cs4031_device::dma2_dack0_w ) |