From 96b97767737058ae6b115fdecbd0b4877657c4d4 Mon Sep 17 00:00:00 2001
From: Curt Coder <curtcoder@mail.com>
Date: Fri, 10 Dec 2010 15:23:01 +0000
Subject: [PATCH] Adjust MC6850 receive/transmit timer periods when clocks are
 changed. [Curt Coder]

---
 src/emu/machine/6850acia.c | 32 ++++++++++++++++++++++++++++++++
 src/emu/machine/6850acia.h |  4 ++--
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/emu/machine/6850acia.c b/src/emu/machine/6850acia.c
index b1474be17a1..1e9a1042b35 100644
--- a/src/emu/machine/6850acia.c
+++ b/src/emu/machine/6850acia.c
@@ -728,6 +728,22 @@ void acia6850_device::rx_clock_in()
 }
 
 
+/*-------------------------------------------------
+    set_rx_clock - set receiver clock 
+-------------------------------------------------*/
+
+void acia6850_device::set_rx_clock(int clock)
+{
+	m_rx_clock = clock;
+
+	if (m_rx_clock)
+	{
+		attotime rx_period = attotime_mul(ATTOTIME_IN_HZ(m_rx_clock), m_divide);
+		timer_adjust_periodic(m_rx_timer, rx_period, 0, rx_period);
+	}
+}
+
+
 /*-------------------------------------------------
     acia6850_set_rx_clock - Set clock frequencies
     dynamically
@@ -739,6 +755,22 @@ void acia6850_set_rx_clock(running_device *device, int clock)
 }
 
 
+/*-------------------------------------------------
+    set_tx_clock - set receiver clock 
+-------------------------------------------------*/
+
+void acia6850_device::set_tx_clock(int clock)
+{
+	m_tx_clock = clock;
+
+	if (m_tx_clock)
+	{
+		attotime tx_period = attotime_mul(ATTOTIME_IN_HZ(m_tx_clock), m_divide);
+		timer_adjust_periodic(m_tx_timer, tx_period, 0, tx_period);
+	}
+}
+
+
 /*-------------------------------------------------
     acia6850_set_tx_clock - Set clock frequencies
     dynamically
diff --git a/src/emu/machine/6850acia.h b/src/emu/machine/6850acia.h
index 0c8c1f782fb..27877031092 100644
--- a/src/emu/machine/6850acia.h
+++ b/src/emu/machine/6850acia.h
@@ -113,8 +113,8 @@ public:
 	void tx_clock_in();
 	void rx_clock_in();
 
-	void set_rx_clock(int clock) { m_rx_clock = clock; }
-	void set_tx_clock(int clock) { m_tx_clock = clock; }
+	void set_rx_clock(int clock);
+	void set_tx_clock(int clock);
 
 protected:
     // device-level overrides