init

main/lipton/vospi.h

@@ -0,0 +1,74 @@
+/*
+ * Lepton VoSPI Module
+ *
+ * Contains the functions to get frames from a Lepton 3.5 via its SPI port.
+ * Optionally supports collecting telemetry when enabled as a footer (does not
+ * support telemetry enabled as a header). 
+ *
+ * Copyright 2020-2022 Dan Julio
+ *
+ * This file is part of tCam.
+ *
+ * tCam 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.
+ *
+ * tCam 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 tCam.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+#include "lepton_system.h"
+
+
+//
+// VoSPI Constants
+//
+
+// LEP_FRAME_USEC is the per-frame period from the Lepton (interrupt rate) 
+#define LEP_FRAME_USEC 9450
+// LEP_MAX_FRAME_XFER_WAIT_USEC specifies the maximum time we should wait in
+// vospi_transfer_segment() to read a valid frame.  It should be LEP_FRAME_USEC -
+// (maximum ISR latency + transfer_packet() code path overhead)
+// than LEP_FRAME_USEC -  maximum ISR latency)
+#define LEP_MAX_FRAME_XFER_WAIT_USEC 9250
+
+#define LEP_WIDTH      160
+#define LEP_HEIGHT     120
+#define LEP_NUM_PIXELS (LEP_WIDTH * LEP_HEIGHT)
+#define LEP_PKT_LENGTH 164
+
+// Telemetry related
+#define LEP_TEL_PACKETS 3
+#define LEP_TEL_PKT_LEN (LEP_PKT_LENGTH - 4)
+#define LEP_TEL_WORDS   (LEP_TEL_PACKETS * LEP_TEL_PKT_LEN / 2)
+
+// Dynamic values depending if telemetry is included or not
+#define LEP_TEL_PKTS_PER_SEG     61
+#define LEP_NOTEL_PKTS_PER_SEG   60
+#define LEP_TEL_WORDS_PER_SEG    (LEP_TEL_PKTS_PER_SEG * LEP_WIDTH / 2)
+#define LEP_NOTEL_WORDS_PER_SEG  (LEP_NOTEL_PKTS_PER_SEG * LEP_WIDTH / 2)
+
+/* Lepton frame error return */
+enum LeptonReadError {
+  NONE, DISCARD, SEGMENT_ERROR, ROW_ERROR, SEGMENT_INVALID
+};
+
+
+
+//
+// VoSPI API
+//
+int vospi_init();
+bool vospi_transfer_segment(uint64_t vsyncDetectedUsec);
+void vospi_get_frame(lep_buffer_t* sys_bufP);
+void vospi_include_telem(bool en);