Decouple hardware specific code from generic, agnostic code

src/avclan/target/avr-attiny3216/media_avr.h

@@ -0,0 +1,32 @@
+/*
+                        AVCLAN-Mockingboard
+    Copyright (C) 2015 Allen Hill <allenofthehills@gmail.com>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+// AVR-internal media-driver hooks, shared between media_avr.c and the bus
+// transaction guard (phy_avr.c's AVCLAN_stopEvent). Not part of the public
+// mediacontrol.h interface.
+
+#ifndef MEDIA_AVR_H
+#define MEDIA_AVR_H
+
+// Keep the TCA0 press waveform roughly in sync while a bus transaction has
+// masked interrupts (runs the OVF ISR body early if an overflow is imminent).
+// MUST be called with interrupts disabled (from within AVCLAN_stopEvent's
+// ATOMIC_BLOCK).
+void mediacontrol_syncDuringMask();
+
+#endif // MEDIA_AVR_H