From 9ab4e449b87b0b8b7a4054927c743fa7dbe062d7 Mon Sep 17 00:00:00 2001
From: Ivan Izaguirre <ivanizag@gmail.com>
Date: Sun, 14 Apr 2019 20:46:40 +0200
Subject: [PATCH] Revert change on keyboard strobe, use it for flow control on
 the stdin keyboard provider

---
 apple2/ansiConsoleFrontend.go | 32 ++++++++++++++++++++------------
 apple2/ioC0Page.go            |  2 +-
 apple2/softSwitches2.go       |  3 ++-
 apple2sdl/sdlKeyboard.go      |  2 +-
 4 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/apple2/ansiConsoleFrontend.go b/apple2/ansiConsoleFrontend.go
index 4fc02cd..5a2fa83 100644
--- a/apple2/ansiConsoleFrontend.go
+++ b/apple2/ansiConsoleFrontend.go
@@ -44,24 +44,32 @@ func (fe *ansiConsoleFrontend) subscribeToTextPages() {
 
 const refreshDelayMs = 100
 
-func (fe *ansiConsoleFrontend) GetKey() (key uint8, ok bool) {
-	stdinReader := func(c chan uint8) {
-		reader := bufio.NewReader(os.Stdin)
-		for {
-			byte, err := reader.ReadByte()
-			if err != nil {
-				fmt.Println(err)
-				return
-			}
-			c <- byte
-		}
-	}
+func (fe *ansiConsoleFrontend) GetKey(strobed bool) (key uint8, ok bool) {
 
+	// Init the first time
 	if fe.keyChannel == nil {
+		stdinReader := func(c chan uint8) {
+			reader := bufio.NewReader(os.Stdin)
+			for {
+				byte, err := reader.ReadByte()
+				if err != nil {
+					fmt.Println(err)
+					return
+				}
+				c <- byte
+			}
+		}
+
 		fe.keyChannel = make(chan uint8, 100)
 		go stdinReader(fe.keyChannel)
 	}
 
+	if !strobed {
+		// We must use the strobe to control the flow from stdin
+		ok = false
+		return
+	}
+
 	select {
 	case key = <-fe.keyChannel:
 		if key == 10 {
diff --git a/apple2/ioC0Page.go b/apple2/ioC0Page.go
index 3e50df2..3cccef8 100644
--- a/apple2/ioC0Page.go
+++ b/apple2/ioC0Page.go
@@ -16,7 +16,7 @@ type softSwitchR func(io *ioC0Page) uint8
 type softSwitchW func(io *ioC0Page, value uint8)
 
 type KeyboardProvider interface {
-	GetKey() (key uint8, ok bool)
+	GetKey(strobe bool) (key uint8, ok bool)
 }
 
 // See https://www.kreativekorp.com/miscpages/a2info/iomemory.shtml
diff --git a/apple2/softSwitches2.go b/apple2/softSwitches2.go
index 8bad68d..0a66df9 100644
--- a/apple2/softSwitches2.go
+++ b/apple2/softSwitches2.go
@@ -93,8 +93,9 @@ func getSoftSwitch(ioFlag uint8, isSet bool) softSwitchR {
 }
 
 func getKeySoftSwitch(io *ioC0Page) uint8 {
+	strobed := (io.softSwitchesData[ioDataKeyboard] & (1 << 7)) == 0
 	if io.keyboard != nil {
-		if key, ok := io.keyboard.GetKey(); ok {
+		if key, ok := io.keyboard.GetKey(strobed); ok {
 			io.softSwitchesData[ioDataKeyboard] = key + (1 << 7)
 		}
 	}
diff --git a/apple2sdl/sdlKeyboard.go b/apple2sdl/sdlKeyboard.go
index 965042b..bb35a73 100644
--- a/apple2sdl/sdlKeyboard.go
+++ b/apple2sdl/sdlKeyboard.go
@@ -93,7 +93,7 @@ func (k *sdlKeyboard) putChar(ch uint8) {
 	k.keyChannel <- ch
 }
 
-func (k *sdlKeyboard) GetKey() (key uint8, ok bool) {
+func (k *sdlKeyboard) GetKey(_ bool) (key uint8, ok bool) {
 	select {
 	case key = <-k.keyChannel:
 		ok = true