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Diffstat (limited to 'src/devices/machine/ins8154.cpp')
-rw-r--r--src/devices/machine/ins8154.cpp71
1 files changed, 52 insertions, 19 deletions
diff --git a/src/devices/machine/ins8154.cpp b/src/devices/machine/ins8154.cpp
index 8a134000f3f..11943cdee2c 100644
--- a/src/devices/machine/ins8154.cpp
+++ b/src/devices/machine/ins8154.cpp
@@ -1,21 +1,24 @@
// license:GPL-2.0+
// copyright-holders:Dirk Best
-/***************************************************************************
+/******************************************************************************
National Semiconductor INS8154
N-Channel 128-by-8 Bit RAM Input/Output (RAM I/O)
TODO: Strobed modes
+ TODO: Check the ODRx register for where to get pin values, _cb() vs m_out_x
-***************************************************************************/
+*******************************************************************************/
#include "emu.h"
#include "ins8154.h"
-#define VERBOSE 1
+#define LOG_BITS (1U << 1)
+//#define VERBOSE (LOG_BITS) // (LOG_GENERAL|LOG_BITS)
#include "logmacro.h"
+#define LOGBITS(...) LOGMASKED(LOG_BITS, __VA_ARGS__)
/***************************************************************************
CONSTANTS
@@ -75,6 +78,7 @@ void ins8154_device::device_start()
save_item(NAME(m_mdr));
save_item(NAME(m_odra));
save_item(NAME(m_odrb));
+ save_item(NAME(m_ram));
}
@@ -94,7 +98,7 @@ void ins8154_device::device_reset()
}
-READ8_MEMBER(ins8154_device::ins8154_r)
+uint8_t ins8154_device::read_io(offs_t offset)
{
uint8_t val = 0xff;
@@ -119,17 +123,23 @@ READ8_MEMBER(ins8154_device::ins8154_r)
break;
default:
- if (offset < 0x08)
+ val = 0;
+ if (offset < 0x08) // Read a bit in Port A
{
if (!m_in_a_cb.isnull())
- val = (m_in_a_cb(0) << (8 - offset)) & 0x80;
- m_in_a = val;
+ {
+ //val = (m_in_a_cb(0) << (8 - offset)) & 0x80;
+ val = (m_in_a_cb(0) & ~m_odra & (1 << (offset & 0x07))) ? 0x80 : 0x00;
+ }
+ LOGBITS("%s: INS8154 Port A read bit %02x: %02x\n", machine().describe_context(), offset & 0x07, val);
}
- else
+ else // Read a bit in Port B
{
if (!m_in_b_cb.isnull())
- val = (m_in_b_cb(0) << (8 - (offset >> 4))) & 0x80;
- m_in_b = val;
+ {
+ val = (m_in_b_cb(0) & ~m_odrb & (1 << (offset & 0x07))) ? 0x80 : 0x00;
+ }
+ LOGBITS("%s: INS8154 Port B read bit %02x: %02x\n", machine().describe_context(), offset & 0x07, val);
}
break;
}
@@ -137,7 +147,12 @@ READ8_MEMBER(ins8154_device::ins8154_r)
return val;
}
-WRITE8_MEMBER(ins8154_device::ins8154_porta_w)
+uint8_t ins8154_device::read_ram(offs_t offset)
+{
+ return m_ram[offset & 0x7f];
+}
+
+void ins8154_device::porta_w(uint8_t data)
{
m_out_a = data;
@@ -146,8 +161,9 @@ WRITE8_MEMBER(ins8154_device::ins8154_porta_w)
m_out_a_cb(offs_t(0), (data & m_odra) | (m_odra ^ 0xff));
}
-WRITE8_MEMBER(ins8154_device::ins8154_portb_w)
+void ins8154_device::portb_w(uint8_t data)
{
+ LOG("%s: INS8154 Write PortB %02x with odrb: %02x\n", machine().describe_context(), data, m_odrb);
m_out_b = data;
/* Test if any pins are set as outputs */
@@ -155,7 +171,7 @@ WRITE8_MEMBER(ins8154_device::ins8154_portb_w)
m_out_b_cb(offs_t(0), (data & m_odrb) | (m_odrb ^ 0xff));
}
-WRITE8_MEMBER(ins8154_device::ins8154_w)
+void ins8154_device::write_io(offs_t offset, uint8_t data)
{
if (offset > 0x24)
{
@@ -166,11 +182,11 @@ WRITE8_MEMBER(ins8154_device::ins8154_w)
switch (offset)
{
case 0x20:
- ins8154_porta_w(space, 0, data);
+ porta_w(data);
break;
case 0x21:
- ins8154_portb_w(space, 0, data);
+ portb_w(data);
break;
case 0x22:
@@ -193,18 +209,35 @@ WRITE8_MEMBER(ins8154_device::ins8154_w)
{
/* Set bit */
if (offset < 0x08)
- ins8154_porta_w(space, 0, m_out_a |= offset & 0x07);
+ {
+ LOGBITS("%s: INS8154 Port A set bit %02x\n", machine().describe_context(), offset & 0x07);
+ porta_w(m_out_a |= (1 << (offset & 0x07)));
+ }
else
- ins8154_portb_w(space, 0, m_out_b |= (offset >> 4) & 0x07);
+ {
+ LOGBITS("%s: INS8154 Port B set bit %02x\n", machine().describe_context(), offset & 0x07);
+ portb_w(m_out_b |= (1 << (offset & 0x07)));
+ }
}
else
{
/* Clear bit */
if (offset < 0x08)
- ins8154_porta_w(space, 0, m_out_a & ~(offset & 0x07));
+ {
+ LOGBITS("%s: INS8154 Port A clear bit %02x\n", machine().describe_context(), offset & 0x07);
+ porta_w(m_out_a & ~(1 << (offset & 0x07)));
+ }
else
- ins8154_portb_w(space, 0, m_out_b & ~((offset >> 4) & 0x07));
+ {
+ LOGBITS("%s: INS8154 Port B clear bit %02x\n", machine().describe_context(), offset & 0x07);
+ portb_w(m_out_b & ~(1 << (offset & 0x07)));
+ }
}
break;
}
}
+
+void ins8154_device::write_ram(offs_t offset, uint8_t data)
+{
+ m_ram[offset & 0x7f] = data;
+}