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-rw-r--r--src/devices/machine/adc0844.cpp208
1 files changed, 208 insertions, 0 deletions
diff --git a/src/devices/machine/adc0844.cpp b/src/devices/machine/adc0844.cpp
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+++ b/src/devices/machine/adc0844.cpp
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+// license: BSD-3-Clause
+// copyright-holders: Dirk Best
+/***************************************************************************
+
+ ADC0844/ADC0848
+
+ A/D Converter With Multiplexer Options
+
+***************************************************************************/
+
+#include "emu.h"
+#include "adc0844.h"
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(ADC0844, adc0844_device, "adc0844", "ADC0844 A/D Converter")
+DEFINE_DEVICE_TYPE(ADC0848, adc0848_device, "adc0848", "ADC0848 A/D Converter")
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// adc0844_device - constructor
+//-------------------------------------------------
+
+adc0844_device::adc0844_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+ device_t(mconfig, type, tag, owner, clock),
+ m_intr_cb(*this),
+ m_ch1_cb(*this), m_ch2_cb(*this), m_ch3_cb(*this), m_ch4_cb(*this),
+ m_conversion_timer(nullptr),
+ m_channel(0x0f),
+ m_result(0xff)
+{
+}
+
+adc0844_device::adc0844_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+ adc0844_device(mconfig, ADC0844, tag, owner, clock)
+{
+}
+
+//-------------------------------------------------
+// adc0848_device - constructor
+//-------------------------------------------------
+
+adc0848_device::adc0848_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+ adc0844_device(mconfig, ADC0848, tag, owner, clock),
+ m_ch5_cb(*this), m_ch6_cb(*this), m_ch7_cb(*this), m_ch8_cb(*this)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void adc0844_device::device_start()
+{
+ // resolve callbacks
+ m_intr_cb.resolve_safe();
+ m_ch1_cb.resolve_safe(0xff);
+ m_ch2_cb.resolve_safe(0xff);
+ m_ch3_cb.resolve_safe(0xff);
+ m_ch4_cb.resolve_safe(0xff);
+
+ // allocate timers
+ m_conversion_timer = timer_alloc();
+
+ // register for save states
+ save_item(NAME(m_channel));
+ save_item(NAME(m_result));
+}
+
+void adc0848_device::device_start()
+{
+ adc0844_device::device_start();
+
+ // resolve callbacks
+ m_ch5_cb.resolve_safe(0xff);
+ m_ch6_cb.resolve_safe(0xff);
+ m_ch7_cb.resolve_safe(0xff);
+ m_ch8_cb.resolve_safe(0xff);
+}
+
+//-------------------------------------------------
+// clamp - restrict value to 0..255
+//-------------------------------------------------
+
+uint8_t adc0844_device::clamp(int value)
+{
+ if (value > 0xff)
+ return 0xff;
+ else if (value < 0)
+ return 0x00;
+ else
+ return value;
+}
+
+//-------------------------------------------------
+// device_timer - handler timer events
+//-------------------------------------------------
+
+void adc0844_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+{
+ switch (m_channel)
+ {
+ // differential
+ case 0x00:
+ case 0x08: m_result = clamp(0xff - (m_ch2_cb(0) - m_ch1_cb(0))); break;
+ case 0x01:
+ case 0x09: m_result = clamp(0xff - (m_ch1_cb(0) - m_ch2_cb(0))); break;
+ case 0x02:
+ case 0x0a: m_result = clamp(0xff - (m_ch4_cb(0) - m_ch3_cb(0))); break;
+ case 0x03:
+ case 0x0b: m_result = clamp(0xff - (m_ch3_cb(0) - m_ch4_cb(0))); break;
+ // single-ended
+ case 0x04: m_result = m_ch1_cb(0); break;
+ case 0x05: m_result = m_ch2_cb(0); break;
+ case 0x06: m_result = m_ch3_cb(0); break;
+ case 0x07: m_result = m_ch4_cb(0); break;
+ // pseudo-differential
+ case 0x0c: m_result = clamp(0xff - (m_ch4_cb(0) - m_ch1_cb(0))); break;
+ case 0x0d: m_result = clamp(0xff - (m_ch4_cb(0) - m_ch2_cb(0))); break;
+ case 0x0e: m_result = clamp(0xff - (m_ch4_cb(0) - m_ch3_cb(0))); break;
+ // undefined
+ case 0x0f: m_result = 0x00; break;
+ }
+
+ m_intr_cb(ASSERT_LINE);
+}
+
+void adc0848_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+{
+ switch (m_channel)
+ {
+ // differential
+ case 0x00:
+ case 0x10: m_result = clamp(0xff - (m_ch2_cb(0) - m_ch1_cb(0))); break;
+ case 0x01:
+ case 0x11: m_result = clamp(0xff - (m_ch1_cb(0) - m_ch2_cb(0))); break;
+ case 0x02:
+ case 0x12: m_result = clamp(0xff - (m_ch4_cb(0) - m_ch3_cb(0))); break;
+ case 0x03:
+ case 0x13: m_result = clamp(0xff - (m_ch3_cb(0) - m_ch4_cb(0))); break;
+ case 0x04:
+ case 0x14: m_result = clamp(0xff - (m_ch6_cb(0) - m_ch5_cb(0))); break;
+ case 0x05:
+ case 0x15: m_result = clamp(0xff - (m_ch5_cb(0) - m_ch6_cb(0))); break;
+ case 0x06:
+ case 0x16: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch7_cb(0))); break;
+ case 0x07:
+ case 0x17: m_result = clamp(0xff - (m_ch7_cb(0) - m_ch8_cb(0))); break;
+ // single-ended
+ case 0x08: m_result = m_ch1_cb(0); break;
+ case 0x09: m_result = m_ch2_cb(0); break;
+ case 0x0a: m_result = m_ch3_cb(0); break;
+ case 0x0b: m_result = m_ch4_cb(0); break;
+ case 0x0c: m_result = m_ch5_cb(0); break;
+ case 0x0d: m_result = m_ch6_cb(0); break;
+ case 0x0e: m_result = m_ch7_cb(0); break;
+ case 0x0f: m_result = m_ch8_cb(0); break;
+ // pseudo-differential
+ case 0x18: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch1_cb(0))); break;
+ case 0x19: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch2_cb(0))); break;
+ case 0x1a: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch3_cb(0))); break;
+ case 0x1b: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch4_cb(0))); break;
+ case 0x1c: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch5_cb(0))); break;
+ case 0x1d: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch6_cb(0))); break;
+ case 0x1e: m_result = clamp(0xff - (m_ch8_cb(0) - m_ch7_cb(0))); break;
+ // undefined
+ case 0x1f: m_result = 0x00; break;
+ }
+
+ m_intr_cb(ASSERT_LINE);
+}
+
+
+//**************************************************************************
+// INTERFACE
+//**************************************************************************
+
+READ8_MEMBER( adc0844_device::read )
+{
+ m_intr_cb(CLEAR_LINE);
+
+ return m_result;
+}
+
+WRITE8_MEMBER( adc0844_device::write )
+{
+ m_intr_cb(CLEAR_LINE);
+
+ // set channel and start conversion
+ m_channel = data & 0x0f;
+ m_conversion_timer->adjust(attotime::from_usec(40));
+}
+
+WRITE8_MEMBER( adc0848_device::write )
+{
+ m_intr_cb(CLEAR_LINE);
+
+ // set channel and start conversion
+ m_channel = data & 0x1f;
+ m_conversion_timer->adjust(attotime::from_usec(40));
+}