From 2b7382a014ffa2925a0534fdfe39a6dd9132e77e Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Tue, 10 Sep 2024 20:59:05 -0400
Subject: [PATCH] Loop in vsync as a potential tape input.

---
 Machines/Oric/Oric.cpp  | 17 ++++++++++++++---
 Machines/Oric/Video.cpp | 15 +++++++++++++++
 Machines/Oric/Video.hpp |  1 +
 3 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/Machines/Oric/Oric.cpp b/Machines/Oric/Oric.cpp
index 3176ddd7e..63f574d62 100644
--- a/Machines/Oric/Oric.cpp
+++ b/Machines/Oric/Oric.cpp
@@ -576,7 +576,9 @@ template <Analyser::Static::Oric::Target::DiskInterface disk_interface, CPU::MOS
 				break;
 			}
 
-			video_ += Cycles(1);
+			if(video_ += Cycles(1)) {
+				set_via_port_b_input();
+			}
 			return Cycles(1);
 		}
 
@@ -621,9 +623,18 @@ template <Analyser::Static::Oric::Target::DiskInterface disk_interface, CPU::MOS
 		}
 
 		// to satisfy Storage::Tape::BinaryTapePlayer::Delegate
-		void tape_did_change_input(Storage::Tape::BinaryTapePlayer *tape_player) final {
+		void tape_did_change_input(Storage::Tape::BinaryTapePlayer *) final {
+			set_via_port_b_input();
+		}
+
+		void set_via_port_b_input() {
 			// set CB1
-			via_.set_control_line_input(MOS::MOS6522::Port::B, MOS::MOS6522::Line::One, !tape_player->get_input());
+			via_.set_control_line_input(
+				MOS::MOS6522::Port::B, MOS::MOS6522::Line::One,
+				tape_player_.get_motor_control() ?
+					!tape_player_.get_input() :
+					!video_->vsync()
+			);
 		}
 
 		// for Utility::TypeRecipient::Delegate
diff --git a/Machines/Oric/Video.cpp b/Machines/Oric/Video.cpp
index a2f7db8c6..42636c636 100644
--- a/Machines/Oric/Video.cpp
+++ b/Machines/Oric/Video.cpp
@@ -115,6 +115,21 @@ bool VideoOutput::vsync() {
 	return counter_ >= v_sync_start_position_ && counter_ < v_sync_end_position_;
 }
 
+Cycles VideoOutput::next_sequence_point() const {
+	if(counter_ < v_sync_start_position_) {
+		return Cycles(v_sync_start_position_ - counter_);
+	} else if(counter_ < v_sync_end_position_) {
+		return Cycles(v_sync_end_position_ - counter_);
+	} else {
+		// After vsync the length of the next frame is baked in, so this is safe
+		// (but should probably be factored out).
+		return Cycles(
+			counter_period_ + static_cast<int>(next_frame_is_sixty_hertz_ ? PAL60VSyncStartPosition : PAL50VSyncStartPosition)
+			- counter_
+		);
+	}
+}
+
 void VideoOutput::run_for(const Cycles cycles) {
 	// Horizontal: 0-39: pixels; otherwise blank; 48-53 sync, 54-56 colour burst.
 	// Vertical: 0-223: pixels; otherwise blank; 256-259 (50Hz) or 234-238 (60Hz) sync.
diff --git a/Machines/Oric/Video.hpp b/Machines/Oric/Video.hpp
index e00a16d69..b3bc5a2ea 100644
--- a/Machines/Oric/Video.hpp
+++ b/Machines/Oric/Video.hpp
@@ -23,6 +23,7 @@ class VideoOutput {
 		void set_colour_rom(const std::vector<uint8_t> &colour_rom);
 
 		void run_for(const Cycles cycles);
+		Cycles next_sequence_point() const;
 
 		bool vsync();