From 35fe4d50d4a919610253d7c18739802c0ae63c35 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Fri, 15 Sep 2017 20:26:41 -0400
Subject: [PATCH] Adds command termination upon drive becoming unready, and
 copies head and drive selection into ST0.

---
 Components/8272/i8272.cpp | 16 +++++++++++++++-
 Components/8272/i8272.hpp | 10 ++++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/Components/8272/i8272.cpp b/Components/8272/i8272.cpp
index 30cbb0cb1..3f02acf15 100644
--- a/Components/8272/i8272.cpp
+++ b/Components/8272/i8272.cpp
@@ -26,7 +26,7 @@ using namespace Intel::i8272;
 
 #define SetBusy()						(main_status_ |= 0x10)
 #define ResetBusy()						(main_status_ &= ~0x10)
-#define Busy()							(main_status_ & 0x10)
+#define IsBusy()						(main_status_ & 0x10)
 
 #define SetAbnormalTermination()		(status_[0] |= 0x40)
 #define SetInvalidCommand()				(status_[0] |= 0x80)
@@ -34,6 +34,7 @@ using namespace Intel::i8272;
 #define SetSeekEnd()					(status_[0] |= 0x20)
 #define SetEquipmentCheck()				(status_[0] |= 0x10)
 #define SetNotReady()					(status_[0] |= 0x08)
+#define SetSide2()						(status_[0] |= 0x04)
 
 #define SetEndOfCylinder()				(status_[1] |= 0x80)
 #define SetDataError()					(status_[1] |= 0x20)
@@ -158,6 +159,11 @@ void i8272::run_for(Cycles cycles) {
 		}
 	}
 
+	// check for busy plus ready disabled
+	if(is_executing_ && !get_drive().get_is_ready()) {
+		posit_event((int)Event8272::NoLongerReady);
+	}
+
 	is_sleeping_ = !delay_time_ && !drives_seeking_ && !head_timers_running_;
 	if(is_sleeping_) update_sleep_observer();
 }
@@ -230,6 +236,7 @@ uint8_t i8272::get_register(int address) {
 #define SET_DRIVE_HEAD_MFM()	\
 	active_drive_ = command_[1]&3;	\
 	active_head_ = (command_[1] >> 2)&1;	\
+	status_[0] = (command_[1]&7);	\
 	select_drive(active_drive_);	\
 	get_drive().set_head((unsigned int)active_head_);	\
 	set_is_double_density(command_[0] & 0x40);
@@ -263,6 +270,10 @@ uint8_t i8272::get_register(int address) {
 
 void i8272::posit_event(int event_type) {
 	if(event_type == (int)Event::IndexHole) index_hole_count_++;
+	if(event_type == (int)Event8272::NoLongerReady) {
+		SetNotReady();
+		goto abort;
+	}
 	if(!(interesting_event_mask_ & event_type)) return;
 	interesting_event_mask_ &= ~event_type;
 
@@ -332,6 +343,7 @@ void i8272::posit_event(int event_type) {
 				}
 				// Establishes the drive and head being addressed, and whether in double density mode; populates the internal
 				// cylinder, head, sector and size registers from the command stream.
+				is_executing_ = true;
 				if(!dma_mode_) SetNonDMAExecution();
 				SET_DRIVE_HEAD_MFM();
 				LOAD_HEAD();
@@ -811,6 +823,7 @@ void i8272::posit_event(int event_type) {
 
 	// Sets abnormal termination of the current command and proceeds to an ST0, ST1, ST2, C, H, R, N result phase.
 	abort:
+		end_writing();
 		SetAbnormalTermination();
 		goto post_st012chrn;
 
@@ -839,6 +852,7 @@ void i8272::posit_event(int event_type) {
 			printf("\n");
 
 			// Set ready to send data to the processor, no longer in non-DMA execution phase.
+			is_executing_ = false;
 			ResetNonDMAExecution();
 			SetDataRequest();
 			SetDataDirectionToProcessor();
diff --git a/Components/8272/i8272.hpp b/Components/8272/i8272.hpp
index 2edab4e24..1907b020e 100644
--- a/Components/8272/i8272.hpp
+++ b/Components/8272/i8272.hpp
@@ -65,6 +65,7 @@ class i8272: public Storage::Disk::MFMController {
 			CommandByte	= (1 << 3),
 			Timer = (1 << 4),
 			ResultEmpty = (1 << 5),
+			NoLongerReady = (1 << 6)
 		};
 		void posit_event(int type);
 		int interesting_event_mask_;
@@ -107,10 +108,11 @@ class i8272: public Storage::Disk::MFMController {
 		bool seek_is_satisfied(int drive);
 
 		// User-supplied parameters; as per the specify command.
-		int step_rate_time_;
-		int head_unload_time_;
-		int head_load_time_;
-		bool dma_mode_;
+		int step_rate_time_ = 1;
+		int head_unload_time_ = 1;
+		int head_load_time_ = 1;
+		bool dma_mode_ = false;
+		bool is_executing_ = false;
 
 		// A count of head unload timers currently running.
 		int head_timers_running_;