From 94231ca3e3bae0a4a46eea27d42f0f5c7fba5921 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Wed, 10 Aug 2022 16:41:45 -0400
Subject: [PATCH] Put word-sizing responsibility on the caller.

---
 Machines/Atari/ST/AtariST.cpp | 5 ++++-
 Machines/Atari/ST/Video.cpp   | 2 +-
 Machines/Atari/ST/Video.hpp   | 2 +-
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Machines/Atari/ST/AtariST.cpp b/Machines/Atari/ST/AtariST.cpp
index 5a350f03d..6925ad85a 100644
--- a/Machines/Atari/ST/AtariST.cpp
+++ b/Machines/Atari/ST/AtariST.cpp
@@ -86,7 +86,10 @@ class ConcreteMachine:
 			}
 			Memory::Fuzz(ram_);
 
-			video_->set_ram(reinterpret_cast<uint16_t *>(ram_.data()), ram_.size());
+			video_->set_ram(
+				reinterpret_cast<uint16_t *>(ram_.data()),
+				ram_.size() >> 1
+			);
 
 			constexpr ROM::Name rom_name = ROM::Name::AtariSTTOS100;
 			ROM::Request request(rom_name);
diff --git a/Machines/Atari/ST/Video.cpp b/Machines/Atari/ST/Video.cpp
index da9412a5a..7549c857c 100644
--- a/Machines/Atari/ST/Video.cpp
+++ b/Machines/Atari/ST/Video.cpp
@@ -132,7 +132,7 @@ Video::Video() :
 
 void Video::set_ram(uint16_t *ram, size_t size) {
 	ram_ = ram;
-	ram_mask_ = int((size >> 1) - 1);
+	ram_mask_ = int(size - 1);
 }
 
 void Video::set_scan_target(Outputs::Display::ScanTarget *scan_target) {
diff --git a/Machines/Atari/ST/Video.hpp b/Machines/Atari/ST/Video.hpp
index 90fc72e19..a467c33cc 100644
--- a/Machines/Atari/ST/Video.hpp
+++ b/Machines/Atari/ST/Video.hpp
@@ -37,7 +37,7 @@ class Video {
 		Video();
 
 		/*!
-			Sets the memory pool that provides video, and its size.
+			Sets the memory pool that provides video, and its size in words.
 		*/
 		void set_ram(uint16_t *, size_t size);