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Diffstat (limited to 'src/mess/machine/md_eeprom.c')
-rw-r--r--src/mess/machine/md_eeprom.c71
1 files changed, 35 insertions, 36 deletions
diff --git a/src/mess/machine/md_eeprom.c b/src/mess/machine/md_eeprom.c
index f1f72500143..6905e0e1df3 100644
--- a/src/mess/machine/md_eeprom.c
+++ b/src/mess/machine/md_eeprom.c
@@ -1,14 +1,14 @@
/***********************************************************************************************************
-
-
+
+
MegaDrive / Genesis cart+EEPROM emulation
-
-
+
+
TODO: proper EEPROM emulation, still not worked on (just hooked up the I2C device)
-
+
i2c games mapping table:
-
+
game name | SDA_IN | SDA_OUT | SCL | SIZE_MASK | PAGE_MASK |
----------------------------------|------------|------------|------------|----------------|-----------|
NBA Jam | 0x200001-0 | 0x200001-0 | 0x200001-1 | 0x00ff (24C02) | 0x03 | xx
@@ -30,7 +30,7 @@
Micro Machines 96 | 0x380001-7 | 0x300000-0*| 0x300000-1*| 0x07ff (24C16) | 0x0f |
Brian Lara Cricket 96 | 0x380001-7 | 0x300000-0*| 0x300000-1*| 0x1fff (24C64) | 0x??* |
----------------------------------|------------|------------|------------|----------------|-----------|
-
+
* Notes: check these
** original Rockman Mega World (J) set uses normal backup RAM
@@ -213,12 +213,12 @@ READ16_MEMBER(md_std_eeprom_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return ~m_i2c_mem & 1;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -237,12 +237,12 @@ READ16_MEMBER(md_eeprom_nbajam_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return m_i2c_mem & 1;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -261,12 +261,12 @@ READ16_MEMBER(md_eeprom_nbajamte_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return m_i2c_mem & 1;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -286,12 +286,12 @@ READ16_MEMBER(md_eeprom_cslam_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return m_i2c_mem & 1;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -311,12 +311,12 @@ READ16_MEMBER(md_eeprom_nflqb_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return m_i2c_mem & 1;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -335,12 +335,12 @@ READ16_MEMBER(md_eeprom_nhlpa_device::read)
{
if (offset == 0x200000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return (m_i2c_mem & 1) << 7;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -359,12 +359,12 @@ READ16_MEMBER(md_eeprom_blara_device::read)
{
if (offset == 0x380000/2)
{
-// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
+// m_i2c_mem = i2cmem_sda_read(m_i2cmem);
return (m_i2c_mem & 1) << 7;
}
- if (offset < 0x400000/2)
- return m_rom[MD_ADDR(offset)];
- else
+ if (offset < 0x400000/2)
+ return m_rom[MD_ADDR(offset)];
+ else
return 0xffff;
}
@@ -378,4 +378,3 @@ WRITE16_MEMBER(md_eeprom_blara_device::write)
i2cmem_sda_write(m_i2cmem, m_i2c_mem);
}
}
-