From 9c8f4ce941939d9ce313d94e36e5a40530945896 Mon Sep 17 00:00:00 2001
From: Andrei Holub <andrei.holub@gmail.com>
Date: Sun, 13 Apr 2025 14:46:12 -0400
Subject: [PATCH] cpu/z80/z80.cpp: Avoided wrong isnuset() detection in some
 Spectrum clones

---
 src/devices/cpu/z80/z80.lst    | 4 ++--
 src/devices/cpu/z80/z80make.py | 1 -
 src/mame/sinclair/chloe.cpp    | 1 -
 src/mame/sinclair/specnext.cpp | 1 -
 src/mame/sinclair/sprinter.cpp | 1 -
 5 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/devices/cpu/z80/z80.lst b/src/devices/cpu/z80/z80.lst
index 97b0a4e22a0..202776169f6 100644
--- a/src/devices/cpu/z80/z80.lst
+++ b/src/devices/cpu/z80/z80.lst
@@ -712,14 +712,14 @@ ffff
 	if (m_busrq_state) {
 		if (!m_busack_state) {
 			m_busack_state = 1;
-			if (busack_en) m_busack_cb(1);
+			m_busack_cb(1);
 		}
 		if (m_icount > 0)
 			m_icount = 0;
 		return;
 	} else if (m_busack_state) {
 		m_busack_state = 0;
-		if (busack_en) m_busack_cb(0);
+		m_busack_cb(0);
 	}
 	call check_interrupts
 	m_after_ei = false;
diff --git a/src/devices/cpu/z80/z80make.py b/src/devices/cpu/z80/z80make.py
index b430c2690ff..0aa7ee1a55e 100644
--- a/src/devices/cpu/z80/z80make.py
+++ b/src/devices/cpu/z80/z80make.py
@@ -292,7 +292,6 @@ class OpcodeList:
         print("", file=f)
         print("const bool nomemrq_en = !m_nomreq_cb.isunset();", file=f)
         print("[[maybe_unused]] const bool refresh_en = !m_refresh_cb.isunset();", file=f)
-        print("const bool busack_en = !m_busack_cb.isunset();", file=f)
         print("", file=f)
         print("bool interrupted = true;", file=f)
         print("while (u8(m_ref) != 0x00) {", file=f)
diff --git a/src/mame/sinclair/chloe.cpp b/src/mame/sinclair/chloe.cpp
index c8af1e9d9e5..03f9e8cc73a 100644
--- a/src/mame/sinclair/chloe.cpp
+++ b/src/mame/sinclair/chloe.cpp
@@ -930,7 +930,6 @@ void chloe_state::chloe(machine_config &config)
 	m_maincpu->set_memory_map(&chloe_state::map_mem);
 	m_maincpu->set_io_map(&chloe_state::map_io);
 	m_maincpu->set_vblank_int("screen", FUNC(chloe_state::chloe_interrupt));
-	m_maincpu->nomreq_cb().set_nop();
 
 	ADDRESS_MAP_BANK(config, m_regs_map).set_map(&chloe_state::map_regs).set_options(ENDIANNESS_LITTLE, 8, 8, 0);
 
diff --git a/src/mame/sinclair/specnext.cpp b/src/mame/sinclair/specnext.cpp
index 9bfd6a11207..8bfb4e7a79b 100644
--- a/src/mame/sinclair/specnext.cpp
+++ b/src/mame/sinclair/specnext.cpp
@@ -3445,7 +3445,6 @@ void specnext_state::tbblue(machine_config &config)
 	m_maincpu->out_nextreg_cb().set(FUNC(specnext_state::reg_w));
 	m_maincpu->in_nextreg_cb().set(FUNC(specnext_state::reg_r));
 	m_maincpu->out_retn_seen_cb().set(FUNC(specnext_state::leave_nmi));
-	m_maincpu->nomreq_cb().set_nop();
 	m_maincpu->busack_cb().set(m_dma, FUNC(specnext_dma_device::bai_w));
 
 	SPECNEXT_CTC(config, m_ctc, 28_MHz_XTAL / 8);
diff --git a/src/mame/sinclair/sprinter.cpp b/src/mame/sinclair/sprinter.cpp
index a01a35d525b..c75066d83db 100644
--- a/src/mame/sinclair/sprinter.cpp
+++ b/src/mame/sinclair/sprinter.cpp
@@ -1883,7 +1883,6 @@ void sprinter_state::sprinter(machine_config &config)
 	m_maincpu->set_m1_map(&sprinter_state::map_fetch);
 	m_maincpu->set_memory_map(&sprinter_state::map_mem);
 	m_maincpu->set_io_map(&sprinter_state::map_io);
-	m_maincpu->nomreq_cb().set_nop();
 	m_maincpu->set_irq_acknowledge_callback(NAME([](device_t &, int){ return 0xff; }));
 	m_maincpu->irqack_cb().set(m_irqs, FUNC(input_merger_any_high_device::in_clear<2>));
 	m_maincpu->irqack_cb().append(m_irqs, FUNC(input_merger_any_high_device::in_clear<1>));