transceiver: separate I/O portion of radio interface implementation
Move push and pull of buffers into a dedicated file. This will
allow us to swap out resampling, non-resampling, and possibly
floating point device interfaces while presenting a single
floating point abstration in the interface itself.
Signed-off-by: Thomas Tsou <ttsou@vt.edu>
git-svn-id: http://wush.net/svn/range/software/public/openbts/trunk@2670 19bc5d8c-e614-43d4-8b26-e1612bc8e597
diff --git a/Transceiver52M/radioIO.cpp b/Transceiver52M/radioIO.cpp
new file mode 100644
index 0000000..9956e87
--- /dev/null
+++ b/Transceiver52M/radioIO.cpp
@@ -0,0 +1,91 @@
+/*
+ * Radio device I/O interface
+ * Written by Thomas Tsou <ttsou@vt.edu>
+ *
+ * Copyright 2011 Free Software Foundation, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ * See the COPYING file in the main directory for details.
+ */
+
+#include <radioInterface.h>
+#include <Logger.h>
+
+/* Device side buffers */
+static short rx_buf[OUTCHUNK * 2 * 2];
+static short tx_buf[INCHUNK * 2 * 2];
+
+/* Complex float to short conversion */
+static int float_to_short(short *shrt_out, float *flt_in, int num)
+{
+ int i;
+
+ for (i = 0; i < num; i++) {
+ shrt_out[2 * i + 0] = flt_in[2 * i + 0];
+ shrt_out[2 * i + 1] = flt_in[2 * i + 1];
+ }
+
+ return i;
+}
+
+/* Comlpex short to float conversion */
+static int short_to_float(float *flt_out, short *shrt_in, int num)
+{
+ int i;
+
+ for (i = 0; i < num; i++) {
+ flt_out[2 * i + 0] = shrt_in[2 * i + 0];
+ flt_out[2 * i + 1] = shrt_in[2 * i + 1];
+ }
+
+ return i;
+}
+
+/* Receive a timestamped chunk from the device */
+void RadioInterface::pullBuffer()
+{
+ bool local_underrun;
+
+ /* Read samples. Fail if we don't get what we want. */
+ int num_rd = mRadio->readSamples(rx_buf, OUTCHUNK, &overrun,
+ readTimestamp, &local_underrun);
+
+ LOG(DEBUG) << "Rx read " << num_rd << " samples from device";
+ assert(num_rd == OUTCHUNK);
+
+ underrun |= local_underrun;
+ readTimestamp += (TIMESTAMP) num_rd;
+
+ short_to_float(rcvBuffer + 2 * rcvCursor, rx_buf, num_rd);
+ rcvCursor += num_rd;
+}
+
+/* Send timestamped chunk to the device with arbitrary size */
+void RadioInterface::pushBuffer()
+{
+ if (sendCursor < INCHUNK)
+ return;
+
+ float_to_short(tx_buf, sendBuffer, sendCursor);
+
+ /* Write samples. Fail if we don't get what we want. */
+ int num_smpls = mRadio->writeSamples(tx_buf,
+ sendCursor,
+ &underrun,
+ writeTimestamp);
+ assert(num_smpls == sendCursor);
+
+ writeTimestamp += (TIMESTAMP) num_smpls;
+ sendCursor = 0;
+}