From 8a78236c6a79c67a0f400d3e4313fa412e99496a Mon Sep 17 00:00:00 2001
From: AJR <ajrhacker@users.noreply.github.com>
Date: Tue, 29 Dec 2020 08:44:32 -0500
Subject: [PATCH] zt8802: Moderate de-skeletonization

---
 src/mame/drivers/zt8802.cpp | 67 +++++++++++++++++++++++++++++++++----
 1 file changed, 61 insertions(+), 6 deletions(-)

diff --git a/src/mame/drivers/zt8802.cpp b/src/mame/drivers/zt8802.cpp
index 3d32d81be2c..027e2132156 100644
--- a/src/mame/drivers/zt8802.cpp
+++ b/src/mame/drivers/zt8802.cpp
@@ -1,12 +1,10 @@
 // license:BSD-3-Clause
-// copyright-holders:
+// copyright-holders:AJR
 /***********************************************************************************************************************************
 
-2017-11-02 Skeleton
-
 Ziatech ZT-8802 single-board computer. Advert says: V40 CPU @ 8MHz, 1MB DRAM, 512K EPROM, 3 RS-232 PORTS.
 
-CPU is NEC D70208L-10 (V40) which is a V20 with 8251,8253,8255 included.
+CPU is NEC D70208L-10 (V40) which is a V20 with 8251,8253,8259 included.
 
 Chips: Maxim MAX249CQH, Exar XT16C452CJPS, Ziatech ICPSMCI-16C49A, 2x GAL22V10D, 2x ACT15245, 2x ACT11245,
        ACT11240, PALCE 16V??-15JC, 2x CYM1465LPD-120C (RAM).
@@ -16,25 +14,82 @@ Other: A 3.6volt battery, a tiny crystal, a red LED, and about 2 dozen jumpers.
 ************************************************************************************************************************************/
 
 #include "emu.h"
+#include "cpu/nec/v5x.h"
+#include "machine/ds1302.h"
 
 class zt8802_state : public driver_device
 {
 public:
 	zt8802_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag)
-		//      , m_maincpu(*this, "maincpu")
+		, m_maincpu(*this, "maincpu")
+		, m_pia(*this, "pia")
+		, m_rtc(*this, "rtc")
 	{ }
 
 	void zt8802(machine_config &config);
+
 private:
-	//  required_device<cpu_device> m_maincpu;
+	void pia_w(offs_t offset, u8 data);
+	u8 rtc_r();
+	void rtc_w(u8 data);
+
+	void mem_map(address_map &map);
+	void io_map(address_map &map);
+
+	required_device<cpu_device> m_maincpu;
+	required_shared_ptr<u8> m_pia;
+	required_device<ds1202_device> m_rtc;
 };
 
+void zt8802_state::pia_w(offs_t offset, u8 data)
+{
+	if (offset == 5)
+		m_rtc->ce_w(BIT(data, 4));
+
+	m_pia[offset] = data;
+}
+
+u8 zt8802_state::rtc_r()
+{
+	if (!machine().side_effects_disabled())
+		m_rtc->sclk_w(0);
+	u8 data = m_rtc->io_r();
+	if (!machine().side_effects_disabled())
+		m_rtc->sclk_w(1);
+	return data;
+}
+
+void zt8802_state::rtc_w(u8 data)
+{
+	m_rtc->sclk_w(0);
+	m_rtc->io_w(BIT(data, 0));
+	m_rtc->sclk_w(1);
+}
+
+void zt8802_state::mem_map(address_map &map)
+{
+	map(0x00000, 0x7ffff).ram();
+	map(0x80000, 0xfffff).rom().region("roms", 0);
+}
+
+void zt8802_state::io_map(address_map &map)
+{
+	map(0x0080, 0x0080).nopr(); // watchdog?
+	map(0xfa00, 0xfa07).ram().share("pia").w(FUNC(zt8802_state::pia_w)); //.rw("pia", FUNC(zt16c49_device::read), FUNC(zt16c49_device::write));
+	map(0xfa80, 0xfa80).rw(FUNC(zt8802_state::rtc_r), FUNC(zt8802_state::rtc_w));
+}
+
 static INPUT_PORTS_START( zt8802 )
 INPUT_PORTS_END
 
 void zt8802_state::zt8802(machine_config &config)
 {
+	V40(config, m_maincpu, 16'000'000);
+	m_maincpu->set_addrmap(AS_PROGRAM, &zt8802_state::mem_map);
+	m_maincpu->set_addrmap(AS_IO, &zt8802_state::io_map);
+
+	DS1202(config, m_rtc, 32'768);
 }
 
 ROM_START( zt8802 )