From: Keith Packard <keithp@keithp.com>
Date: Sun, 5 Jun 2011 00:58:51 +0000 (-0700)
Subject: src-avr: Run CPU at 8MHz, even with a 16MHz xtal
X-Git-Url: https://git.gag.com/?a=commitdiff_plain;ds=sidebyside;h=e0ebdb4468db84a8e7f83043103e4b3bac928b74;p=fw%2Faltos

src-avr: Run CPU at 8MHz, even with a 16MHz xtal

This allows the Teensy to run at 3.3V.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/src-avr/ao_timer.c b/src-avr/ao_timer.c
index f0918a7d..aec40475 100644
--- a/src-avr/ao_timer.c
+++ b/src-avr/ao_timer.c
@@ -140,7 +140,13 @@ ao_clock_init(void)
 	/* Disable the clock prescaler */
 	cli();
 	CLKPR = (1 << CLKPCE);
+
+	/* Always run the system clock at 8MHz */
+#if AVR_CLOCK > 12000000UL
+	CLKPR = 1;
+#else
 	CLKPR = 0;
+#endif
 	sei();
 
 	/* Set up the PLL to use the crystal */