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mc6845: Display Start Address is write-only on MC6845, and read-write on HD6845S

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This commit is contained in:
mahlemiut 2015-11-05 15:39:40 +13:00
parent 2ad9fcee0f
commit 2a43785f2f
1 changed files with 2 additions and 2 deletions
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4
src/devices/video/mc6845.c
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@ -1032,7 +1032,7 @@ void mc6845_device::device_start()
m_max_ras_addr = 0x1f;
m_vert_char_total = 0x7f;
m_supports_disp_start_addr_r = true;
m_supports_disp_start_addr_r = false; // MC6845 can not read Display Start (double checked on datasheet)
m_supports_vert_sync_width = false;
m_supports_status_reg_d5 = false;
m_supports_status_reg_d6 = false;
@ -1168,7 +1168,7 @@ void hd6845_device::device_start()
{
mc6845_device::device_start();
m_supports_disp_start_addr_r = false;
m_supports_disp_start_addr_r = true; // HD6845S can definitely read Display Start (double checked on datasheet)
m_supports_vert_sync_width = true;
m_supports_status_reg_d5 = false;
m_supports_status_reg_d6 = false;