// 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)); }