SSTV transmit beta (320x256 24bpp Scottie 2 only)

firmware/baseband/CMakeLists.txt

@@ -387,6 +387,13 @@ set(MODE_CPPSRC
 )
 DeclareTargets(PREP replay)
 
+### SSTV TX
+
+set(MODE_CPPSRC
+	proc_sstvtx.cpp
+)
+DeclareTargets(PSTX sstvtx)
+
 ### Tones
 
 set(MODE_CPPSRC

firmware/baseband/proc_sstvtx.cpp

@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
+ * Copyright (C) 2016 Furrtek
+ * 
+ * This file is part of PortaPack.
+ *
+ * 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 2, 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; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "proc_sstvtx.hpp"
+#include "sine_table_int8.hpp"
+#include "event_m4.hpp"
+
+#include <cstdint>
+
+// This is called at 3072000/2048 = 1500Hz
+void SSTVTXProcessor::execute(const buffer_c8_t& buffer) {
+	
+	if (!configured) return;
+	
+	for (size_t i = 0; i < buffer.count; i++) {
+		
+		if (!sample_count) {
+			
+			// This FSM is a mess. It seems to do a lot where it shouldn't (I/Q loop),
+			// but it actually doesn't do much. Used for sequencing the different parts
+			// of the scanline. Todo: simplify !
+			
+			if (state == STATE_CALIBRATION) {
+				// Once per scanline
+				tone_delta = calibration_sequence[substep].first;
+				sample_count = calibration_sequence[substep].second;
+				if (substep == 2) {
+					substep = 0;
+					state = STATE_VIS;
+				} else
+					substep++;
+			} else if (state == STATE_VIS) {
+				// Once per scanline
+				if (substep == 10) {
+					current_scanline = &scanline_buffer[buffer_flip];
+					buffer_flip ^= 1;
+					if (asked == false) {
+						// Ask application for a new scanline
+						shared_memory.application_queue.push(sig_message);
+						asked = true;
+					}
+					if (current_scanline->start_tone.duration) {
+						state = STATE_START;
+						tone_delta = current_scanline->start_tone.frequency;
+						sample_count = current_scanline->start_tone.duration;
+					} else {
+						state = STATE_PIXELS;
+						tone_delta = current_scanline->gap_tone.frequency;
+						sample_count = current_scanline->gap_tone.duration;
+					}
+				} else {
+					tone_delta = vis_code_sequence[substep];
+					sample_count = SSTV_MS2S(30);	// VIS code bit is 30ms
+					substep++;
+				}
+			} else if (state == STATE_START) {
+				// Once per scanline, optional
+				state = STATE_PIXELS;
+				tone_delta = current_scanline->gap_tone.frequency;
+				sample_count = current_scanline->gap_tone.duration;
+			} else if (state == STATE_PIXELS) {
+				// Many times per scanline
+				pixel_luma = current_scanline->luma[pixel_index];
+				
+				pixel_index++;
+				
+				tone_delta = SSTV_F2D(1500 + ((pixel_luma * 800) / 256));
+				
+				sample_count = pixel_duration;
+				
+				if (pixel_index >= 320) {
+					// Scanline done, (dirty) state jump
+					pixel_index = 0;
+					state = STATE_VIS;
+					substep = 10;
+				}
+			}
+		} else {
+			sample_count--;
+		}
+
+		tone_sample = (sine_table_i8[(tone_phase & 0xFF000000U) >> 24]);
+		tone_phase += tone_delta;
+		
+		// FM
+		delta = tone_sample * fm_delta;
+		
+		phase += delta;
+		sphase = phase + (64 << 24);
+
+		re = (sine_table_i8[(sphase & 0xFF000000U) >> 24]);
+		im = (sine_table_i8[(phase & 0xFF000000U) >> 24]);
+		
+		buffer.p[i] = {re, im};
+	}
+}
+
+void SSTVTXProcessor::on_message(const Message* const msg) {
+	const auto message = *reinterpret_cast<const SSTVConfigureMessage*>(msg);
+	
+	switch(msg->id) {
+		case Message::ID::SSTVConfigure:
+			pixel_duration = message.pixel_duration;
+			
+			if (!pixel_duration) {
+				configured = false;
+				return;
+			}
+			
+			vis_code = message.vis_code;
+			
+			// VIS code:
+			// 1200
+			// 00011101 (0=1300, 1=1100)
+			// 1200
+			vis_code_sequence[0] = SSTV_VIS_SS;
+			for (uint32_t c = 0; c < 8; c++) {
+				vis_code_sequence[c + 1] = ((vis_code << c) & 0x80) ? SSTV_VIS_ONE : SSTV_VIS_ZERO;
+			}
+			vis_code_sequence[9] = SSTV_VIS_SS;
+			
+			fm_delta = 9000 * (0xFFFFFFULL / 3072000);	// Fixed for now
+			
+			pixel_index = 0;
+			sample_count = 0;
+			tone_phase = 0;
+			state = STATE_CALIBRATION;
+			substep = 0;
+			
+			configured = true;
+			break;
+		
+		case Message::ID::FIFOData:
+			memcpy(&scanline_buffer[buffer_flip], static_cast<const FIFODataMessage*>(msg)->data, sizeof(sstv_scanline));
+			asked = false;
+			break;
+
+		default:
+			break;
+	}
+}
+
+int main() {
+	EventDispatcher event_dispatcher { std::make_unique<SSTVTXProcessor>() };
+	event_dispatcher.run();
+	return 0;
+}

firmware/baseband/proc_sstvtx.hpp

@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
+ * Copyright (C) 2016 Furrtek
+ * 
+ * This file is part of PortaPack.
+ *
+ * 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 2, 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; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __PROC_SSTV_TX_H__
+#define __PROC_SSTV_TX_H__
+
+#include "portapack_shared_memory.hpp"
+#include "baseband_processor.hpp"
+#include "baseband_thread.hpp"
+#include "sstv.hpp"
+
+using namespace sstv;
+
+class SSTVTXProcessor : public BasebandProcessor {
+public:
+	void execute(const buffer_c8_t& buffer) override;
+	
+	void on_message(const Message* const p) override;
+
+private:
+
+	// 1900 300ms
+	// 1200 10ms
+	// 1900 300ms
+	const std::pair<uint32_t, uint32_t> calibration_sequence[3] = {
+		{ SSTV_F2D(1900), SSTV_MS2S(300) },
+		{ SSTV_F2D(1200), SSTV_MS2S(10) },
+		{ SSTV_F2D(1900), SSTV_MS2S(300) }
+	};
+	
+	enum state_t {
+		STATE_CALIBRATION = 0,
+		STATE_VIS,
+		STATE_START,
+		STATE_PIXELS
+	};
+	
+	state_t state { };
+	
+	bool configured { false };
+	
+	BasebandThread baseband_thread { 3072000, this, NORMALPRIO + 20, baseband::Direction::Transmit };
+
+	uint32_t vis_code_sequence[10] { };
+	sstv_scanline scanline_buffer[2] { };
+	uint8_t buffer_flip { 0 }, substep { 0 };
+	
+	uint8_t vis_code { };
+	uint32_t pixel_duration { };
+
+	sstv_scanline * current_scanline { };
+	
+	uint8_t pixel_luma { };
+	uint32_t fm_delta { 0 };
+	uint32_t tone_phase { 0 };
+	uint32_t tone_delta { 0 };
+    uint32_t pixel_index { 0 };
+    uint32_t sample_count { 0 };
+	uint32_t phase { 0 }, sphase { 0 };
+	int32_t tone_sample { 0 }, delta { 0 };
+	int8_t re { 0 }, im { 0 };
+	
+	bool asked { false };
+	
+	RequestSignalMessage sig_message { RequestSignalMessage::Signal::FillRequest };
+};
+
+#endif