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Mac II Midi Demo
Volume Number:3
Issue Number:12
Column Tag:The Midi Mac

A Midi Demo for the Mac II

By Kirk Austin, Contributing Editor, San Rafael, CA

Here we are back in MIDI land again. This is a continuation of the July 1987 article in which we bacame familiar with what MIDI is all about, and looked into some of the low level routines that are necessary to work with MIDI on the Macintosh.

Now, probably what I didn’t tell you last time was that these low level routines were designed to work with LightSpeed Pascal from Think Technologies. I have found that this is the easiest development system for people just starting to program the Macintosh because of its unique source level debugging features. Also, I have found the Pascal language to be the best choice among languages available for the Macintosh because the Macintosh was designed with the Pascal language in mind. Because of this all of the documentation is written with a Pascal syntax (Inside Macintosh, Macintosh Revealed, etc.).

As a result of this built-in bias, if any other language than Pascal is chosen as a development tool, a great deal of time is typically spent just translating from the Pascal documentation to whatever language you have decided to use. The moral of the story is, if you are just starting out programming the Macintosh, you would be doing yourself a big favor by choosing Pascal as your development language, ‘nuff said.

The Apple Music Fair

On July 10th Apple had an in-house party to let its employees find out more about music programs for the Macintosh. It was a great party, with food and drinks in the courtyard of the DeAnza 3 building. About a dozen or so companies with music products for the Macintosh were present, showing their wares, and there was even a presentation by Alan Kay on the future of computers and music.

I was impressed by the fact that Apple is making an effort to get its employees excited about the musical possibilities of the Macintosh computer. The Mac has become the defacto standard for MIDI controllers. If you attend one of the biannual NAMM shows (which is where all of the new musical products are exhibited) you will find that the Macintosh has taken over as far as musical computers go. I just wish Apple would go a little bit further with their support of MIDI. For instance, I know that there are MIDI routines built into the new ROM’s on the Macintosh II, but I can’t get anyone at Apple to tell me what they are. Now, obviously, someone there knows what the routines are, after all, someone had to write them in the first place, right? But, for some reason, Apple is not releasing the information just yet. I hope this changes soon, as I would like to be using ROM routines instead of having to write all of my own code, but I guess I will just have to wait a while (sigh).

By the way, I heard that copies of the July issue of MacTutor are making the rounds at Apple and I have gotten inquiries about the MIDI routines from some Apple employees. Maybe I can stir up enough interest at Apple to get them to come through with some information (are you listening, guys?).

Whoops!

Unfortunately, there was a slight oversight on my part in the program listings that were printed in July that caused a bug in the interrupt handlers. If you are using the low level routines in a program that uses input from the Macintosh keyboard, the status register can become corrupted by the MIDI interrupt routines and the computer will think that it is getting a never-ending string of keystrokes from the ASCII keyboard. I get a string of lower case “c”, but othere people have reported getting lower case “s”.

Anyway, the problem is that I neglected to save and restore the status register in the interrupt routines, so you need to add the following two lines to the four interrupt handlers (i.e. TxIntHandA, TxIntHandB, RxIntHandA, and RxIntHandB):

This should be the first line at the beginning of each routine:

 MOVE  SR,-(SP)

then, replace the line

 ANDI  #$F8FF,SR

at the end of each interrupt handler with the following line

 MOVE  (SP)+,SR

This change keeps the status register intact instead of changing its value after the interrupt routine has executed. Sorry if this error has caused anyone a great deal of hair pulling.

New Changes to LLMIDI

There are also a couple of additional routines that I have added to the library since it was published. The revised routine library is available on the source code disk for July, so if you just buy that you will save yourself an awful lot of typing. Also, there is the distinct possibility that if you do type the listings in yourself that you will make a typo and it will get flagged as an assembly error. The listings on the source code disk have been assembled with MDS without any errors being flagged, so if you are showing an error it is probably a typo.

Anyway, the new additions to the library have to do with filtering out “active sensing” MIDI bytes from the data stream, and also adding a MIDI thru function that echoes the incoming MIDI data on either the same port or the opposite one.

Active Sensing

This is a data byte that is sent out by some controllers every 300 milliseconds or so that lets receiving equipment know that everything is hunky dory. Mostly, it just gets in the way of whatever you might be trying to do with the MIDI data stream, so the best thing to do is just filter it out before it gets placed in the buffer. A slight change to the RxIntHand routines is all that is necessary to do this, and it consists of a grand total of two lines of assembly code.

MIDI Thru

The MIDI thru capability is pretty easy to add too. It’s another change to the RxIntHand routines that calls either TxMIDIA or TxMIDIB depending on the variable ThruFlagA or ThruFlagB. In order to set the variables two routines had to be added to the library: MIDIThruA and MIDIThruB.

The new routines

{1}
XDEF  MIDIThruA
XDEF  MIDIThruB
ThruFlagA  DC 0  ; MIDI thru flag for modem port
ThruFlagB  DC 0  ; MIDI thru flag for printer port
 
; This routine lets you do a MIDI Thru function
; The Thrucode is:
; 0 = No thru function
; 1 = MIDI thru on the same channel
; 2 = MIDI thru on the opposite channel

; Procedure MIDIThruA(Thrucode : integer);
MIDIThruA
 LEA  ThruFlagA,A0  ; point to the flag
 MOVE  4(SP),(A0)  ; set the flag
 MOVE.L  (SP)+,A0  ; save the return address
 ADDQ  #2,SP     ; move past the parameter
 MOVE.L  A0,-(SP)  ; put the return address back
 RTS      ; and return
 
; This is the interrupt routine for receiving through the
; modem port. It places the counter value and the MIDI byte in
; a circular queue to be accessed later by the application.
; When the system gets this far, A0 contains the SCC base read
; Ctl address and A1 contains the SCC base write Ctl address
; for this channel. The data addresses are offset by 4 from 
; the control addresses. D0-D3/A0-A3 are already preserved, so 
; they may be used freely.

RxIntHandA
 MOVE  SR,-(SP)  ; save status register
 ORI  #$0300,SR  ; disable interrupts
 
@3 MOVE  #4,D0   ; get data offset
 CLR.L  D1       ; prepare for data
 MOVE.L  (SP),(SP)   ; Delay
 MOVE.B  0(A0,D0),D1    ; read data from SCC
 MOVE.L  (SP),(SP)   ; Delay
 CMPI  #$FE,D1   ; filter out acitve sensing
 BEQ  @2
 LEA  ThruFlagA,A1   ; 
 CMPI  #1,(A1)   ; check for MIDI Thru
 BNE  @4
 MOVE  D1,-(SP)  ; put data on the stack
 BSR  TxMIDIA    ; send it out port A
@4

 LEA  ThruFlagA,A1   ;
 CMPI  #2,(A1)   ; check for MIDI Thru
 BNE  @5
 MOVE  D1,-(SP)  ; put data on the stack
 BSR  TxMIDIB    ; send it out port B
@5
 LEA  RxQueueA,A2  ; point to queue
 LEA  RxByteInA,A3   ; get the address
 MOVE  (A3),D0   ; get offset to next cell
 LEA  Counter,A3   ; get the address
 MOVE.L  (A3),D2   ; put counter value in D2
 LSL.L  #8,D2    ; shift counter one byte
 ADD.L  D2,D1    ; combine counter and data
 MOVE.L  D1,0(A2,D0)    ; put longword in queue
 LEA  RxQEmptyA,A3   ; get the address
 MOVE  #0,(A3)   ; reset queue empty flag
 ADDQ  #4,D0     ; update index
 CMP  #$400,D0
 BNE  @1
 MOVE  #0,D0
@1 LEA  RxByteInA,A3      ; get the address
 MOVE  D0,(A3)
 
@2 BTST.B  #0,(A0)   ; is there more data?
 BNE  @3    ; do it again if there is
 
 MOVE  (SP)+,SR  ; restore status register
 RTS      ; and return
  
; This is the interrupt routine for transmitting a byte
; through the modem port. It checks to see if there is any 
; data to send, and if there is it sends it to the SCC.  If
; there isn’t it resets the TBE interrupt in the SCC and 
; exits. When the system gets this far, A0 contains the SCC 
; base read Ctl address and A1 contains the SCC base write Ctl 
; address for this channel. The data addresses are offset by 4 
; from the control addresses. D0-D3/A0-A3 are already pre
; served, so they may be used freely.

TxIntHandA
 MOVE  SR,-(SP)  ; save the status register
 ORI  #$0300,SR  ; disable interrupts
  
 LEA  TxQEmptyA,A3   ; get the address
 TST.B  (A3)     ; Is queue empty?
 BEQ  @1    ; if not branch
 MOVE.B  #$28,(A1)   ; if so, reset TBE interrupt
 MOVE.L  (SP),(SP)   ; Delay
 BRA  TxIExitA   ; and exit
@1 LEA  TxByteOutA,A3     ; get the address
 MOVE  (A3),D0   ; get index to next data byte
 LEA  TxQueueA,A2  ; point to queue
 MOVE  #4,D1     ; get data offset
 MOVE.B  0(A2,D0),0(A1,D1)  ; write data to SCC
 MOVE.L  (SP),(SP)   ; Delay
 ADDQ  #1,D0     ; update index
 CMP  #$100,D0
 BNE  @2
 MOVE  #0,D0
@2 LEA  TxByteOutA,A3     ; get the address
 MOVE  D0,(A3)
 LEA  TxByteInA,A3   ; get the address
 MOVE  (A3),D1
 CMP  D0,D1      ; is TxQueue empty?
 BNE  TxIExitA   ; if not exit
 LEA  TxQEmptyA,A3   ; get the address
 MOVE  #$FFFF,(A3)   ; if empty set flag
 
TxIExitA
 MOVE  (SP)+,SR  ; restore status register
 RTS      ; and return

; This routine lets you do a MIDI Thru function
; The Thrucode is:
;  0 = No thru function
;  1 = MIDI thru on the same channel
;  2 = MIDI thru on the opposite channel
; Procedure MIDIThruB(Thrucode : integer);

MIDIThruB
 LEA  ThruFlagB,A0   ; point to the flag
 MOVE  4(SP),(A0)  ; set the flag
 MOVE.L  (SP)+,A0  ; save the return address
 ADDQ  #2,SP     ; move past the parameter
 MOVE.L  A0,-(SP)  ; put the return address back
 RTS      ; and return
 
; This is the interrupt routine for receiving through the
; printer port. It places the counter value and the MIDI byte
; in a circular queue to be accessed later by the appl-
; ication. When the system gets this far, A0 contains the SCC
; base read Ctl address and A1 contains the SCC base write Ctl
; address for this channel. The data addresses are offset by 4
; from the control addresses. D0-D3/A0-A3 are already pre-
; served, so they may be used freely.

RxIntHandB
 MOVE  SR,-(SP)  ; save status register
 ORI  #$0300,SR  ; disable interrupts
  
@3 MOVE  #4,D0   ; get data offset
 CLR.L  D1       ; prepare for data
 MOVE.L  (SP),(SP)   ; Delay
 MOVE.B  0(A0,D0),D1      ; read data from SCC
 MOVE.L  (SP),(SP)   ; Delay
 CMPI  #$FE,D1   ; filter out acitve sensing
 BEQ  @2
 LEA  ThruFlagB,A1
 CMPI  #1,(A1)   ; check for MIDI Thru
 BNE  @4
 MOVE  D1,-(SP)  ; put data on the stack
 BSR  TxMIDIB    ; send it out port B
@4
 LEA  ThruFlagB,A1
 CMPI  #2,(A1)   ; check for MIDI Thru
 BNE  @5
 MOVE  D1,-(SP)  ; put data on the stack
 BSR  TxMIDIA    ; send it out port A
@5
 LEA  RxQueueB,A2  ; point to queue
 LEA  RxByteInB,A3   ; get the address
 MOVE  (A3),D0   ; get offset to next cell
 LEA  Counter,A3   ; get the address
 MOVE.L  (A3),D2   ; put counter value in D2
 LSL.L  #8,D2    ; shift counter one byte
 ADD.L  D2,D1    ; combine counter and data
 MOVE.L  D1,0(A2,D0)      ; put longword in queue
 LEA  RxQEmptyB,A3   ; get the address
 MOVE  #0,(A3)   ; reset queue empty flag
 ADDQ  #4,D0     ; update index
 CMP  #$400,D0
 BNE  @1
 MOVE  #0,D0
@1 LEA  RxByteInB,A3      ; get the address
 MOVE  D0,(A3)
  
@2 BTST.B  #0,(A0)   ; is there more data?
 BNE  @3    ; do it again if there is
 
 MOVE  (SP)+,SR  ; restore status register
 RTS      ; and return
  
; This is the interrupt routine for transmitting a byte
; through the printer port.
; It checks to see if there is any data to send, and if there
; is it sends it to the SCC.  If there isn’t it resets the TBE
; interrupt in the SCC and exits. When the system gets this
; far, A0 contains the SCC base read Ctl address and A1
; contains the SCC base write Ctl address for this channel. 
; The data addresses are offset by 4 from the control addr-
; esses. D0-D3/A0-A3 are already preserved, so they may be 
; used freely.

TxIntHandB
 MOVE  SR,-(SP)  ; save status register
 ORI  #$0300,SR  ; disable interrupts
  
 LEA  TxQEmptyB,A3   ; get the address
 TST.B  (A3)     ; Is queue empty?
 BEQ  @1    ; if not branch
 MOVE.B  #$28,(A1)   ; if so, reset TBE interrupt
 MOVE.L  (SP),(SP)   ; Delay
 BRA  TxIExitB   ; and exit
@1 LEA  TxByteOutB,A3     ; get the address
 MOVE  (A3),D0   ; get index to next data byte
 LEA  TxQueueB,A2  ; point to queue
 MOVE  #4,D1     ; get data offset
 MOVE.B  0(A2,D0),0(A1,D1)  ; write data to SCC
 MOVE.L  (SP),(SP)   ; Delay
 ADDQ  #1,D0     ; update index
 CMP  #$100,D0
 BNE  @2
 MOVE  #0,D0
@2 LEA  TxByteOutB,A3     ; get the address
 MOVE  D0,(A3)
 LEA  TxByteInB,A3   ; get the address
 MOVE  (A3),D1
 CMP  D0,D1      ; is TxQueue empty?
 BNE  TxIExitB   ; if not exit
 LEA  TxQEmptyB,A3   ; get the address
 MOVE  #$FFFF,(A3)   ; if empty set flag
 
TxIExitB
 MOVE  (SP)+,SR  ; restore status register
 RTS      ; and return

The World’s dumbest MIDI program

This brings us to an actual example of how to use these routines in a typical program. For the example program I have chosen to make the Macintosh into the worlds most expensive MIDI thru box. Actually, it reminds me of when I first got my Macintosh in 1984 with just MacPaint and MacWrite available. I used to call it the $2,000 etch-a-sketch (ha ha).

At any rate, the demo program MIDI Shell lets you test out the various modes of MIDI thru by using menu selections. I also added some of my preferred techniques for writing applications in general, such as including a Transfer... menu item in the file Menu, and using an About... dialog box that doesn’t get in the user’s way.

What I mean by that last statement is that most About... boxes that I see force you to click on an OK button or something in order to continue working in the program. Now, there are some cases where you don’t have to click in the dialog box itself, but you can’t just go up and make a normal menu selection because you have to click once just to get rid of the dialog first (the finder’s About... box is an example of this way to handle it). My feeling is that the optimum way to deal with the About... dialog box is to make it possible to use the program without having to concern yourself with getting rid of the dialog box first. This is accomplished by using the scheme presented in the DoAbout procedure.

The Transfer... item in the File menu is one that I wish were in every Macintosh program. It makes life much easier by not making the user have to go back to the Finder all the time. Considering that it is so simple to implement, I end up using it in every program I write.

More ways to skin the cat

Now, I should probably point out at this time that there are other ways to deal with MIDI input and output besides the interrupt method that I have described so far. There is also a technique known as polling.

Polling is done by dropping all other considerations and just constantly looking at the receive register of the SCC chip to see if there is anything there. While it may sound really dumb at first, polling can be very useful in certain circumstances, like when you know exactly when a large amount of MIDI data is going to arrive. This happens in programs like patch librarians, for example.

Now, of course, doing polling requires an entirely different set of low level routines. Next article I’ll show you some of these routines and how to write a simple patch librarian with them. Then, in a later article, I’ll come back to the interrupt driven library to look at writing a ‘Stone Age Sequencer’. Until then, happy coding.

{2}
{ Kirk Austin, 7/12/87 }
{ This is an example program that illustrates the } 
{following techniques: }
{ My preferred method for handling the about box }
{The use of the transfer command in the file menu }
{The use of the LSPMIDI library including MIDIThru}

PROGRAM ShellExample;

 USES
 LSPMIDI;
{ Global Constants }
 CONST
 Null = ‘’;
 AppleMenuID = 1;
 FileMenuID = 2;
 EditMenuID = 3;
 MIDIMenuID = 4;
 AboutID = 200;
{ Global Variables }
 VAR
 myMenus : ARRAY[AppleMenuID..MIDIMenuID] OF MenuHandle;
 Done : Boolean; { true when user selects quit}
{This is a way to do the about box so that it doesn’t interfere with 
the application. For instance, you can make menu selections while the 
about box is visible.}

 PROCEDURE ShowAbout;
 VAR
 theDlog : DialogPtr;
 oldPort : GrafPtr;
 BEGIN
 GetPort(oldPort);
 theDlog := GetNewDialog(AboutID, NIL, Pointer(-1));
 SetPort(theDlog);
 DrawDialog(theDlog);
 WHILE NOT Button DO
 ;
 DisposDialog(theDlog);
 SetPort(oldPort);
 END;

 PROCEDURE LaunchIt (mode : integer;
 VAR fName : Str255);
 INLINE
 $204F, {movea.l  a7,a0;(a0) is string ptr, 4(a0) mode}
 $A9F2; {_Launch}


 PROCEDURE DoXfer;
 VAR
 where : Point;
 reply : SFReply;
 vRef : integer;
 thefName : Str255;
 textType : SFTypeList;
 BEGIN
 where.h := 80;
 where.v := 55;
 textType[0] := ‘APPL’;
 SFGetFile(where, Null, NIL, 1, textType, NIL, reply);
 WITH reply DO
 IF NOT good THEN
 thefName := Null
 ELSE
 BEGIN
 thefName := fName;
 vRef := vRefNum
 END;
 IF thefName <> Null THEN
 BEGIN
 Done := true;
 IF SetVol(NIL, vRef) = noErr THEN
 BEGIN
 ResetSCCA;
 ResetSCCB;
 QuitTimer;
 LaunchIt(0, thefName)
 END;
 END
 END;

 PROCEDURE ProcessMenu ( codeWord : Longint);
 { handle menu selections}
 VAR
 i : integer;
 menuNum : Integer;
 TheMenuHdle : MenuHandle;
 itemNum : Integer;
 NameHolder : str255;
 dummy : Integer;
 ignore : boolean;
 TheValue : longint;

 BEGIN
 IF codeWord <> 0 THEN  { nothing was selected}
 BEGIN
 menuNum := HiWord(codeWord);
 itemNum := LoWord(codeWord);
 CASE menuNum OF { the different menus}
 AppleMenuID : 
 BEGIN
 IF itemNum < 3 THEN
 BEGIN
 ShowAbout;
 END
 ELSE
 BEGIN
 GetItem(myMenus[AppleMenuID], itemNum, NameHolder);
 dummy := OpenDeskAcc(NameHolder);
 END;
 END;
 FileMenuID : 
 BEGIN
 CASE ItemNum OF
 1 : 
 BEGIN
 DoXfer;
 END;
 2 : 
 BEGIN
 Done := true;
 END;
 END;
 END;
 EditMenuID : 
 BEGIN
 ignore := SystemEdit(itemNum - 1);
 END;
 MIDIMenuID : 
 BEGIN
 TheMenuHdle := GetMHandle(4);
 FOR i := 1 TO 5 DO
 CheckItem(TheMenuHdle, i, false);
 MIDIThruA(0);
 MIDIThruB(0);
 CASE ItemNum OF
 1 : 
 BEGIN
 CheckItem(TheMenuHdle, 1, true);
 MIDIThruA(1);
 END;
 2 : 
 BEGIN
 CheckItem(TheMenuHdle, 2, true);
 MIDIThruA(2);
 END;
 3 : 
 BEGIN
 CheckItem(TheMenuHdle, 3, true);
 MIDIThruB(1);
 END;
 4 : 
 BEGIN
 CheckItem(TheMenuHdle, 4, true);
 MIDIThruB(2);
 END;
 5 : 
 BEGIN
 CheckItem(TheMenuHdle, 5, true);
 MIDIThruA(0);
 MIDIThruB(0);
 END;
 END;
 END;
 END;
 HiliteMenu(0);
 END;
 END;

 PROCEDURE DealWithMouseDowns (theEvent : EventRecord);
 VAR
 location : Integer;
 windowPointedTo : WindowPtr;
 mouseLoc : point;
 windowLoc : integer;
 VandH : Longint;
 Height : Integer;
 Width : Integer;
 BEGIN
 mouseLoc := theEvent.where;
 windowLoc := FindWindow(mouseLoc, windowPointedTo);
 CASE windowLoc OF
 inMenuBar : 
 BEGIN
 ProcessMenu(MenuSelect(mouseLoc));
 END;
 inSysWindow : 
 BEGIN
 SystemClick(theEvent, windowPointedTo);
 END;
 OTHERWISE
 BEGIN
 END;
 END;
 END;

 PROCEDURE DealWithKeyDowns (theEvent : EventRecord);
 TYPE
 Trick = PACKED RECORD
 CASE boolean OF
 true : (
 long : Longint
 );
 false : (
 chr3, chr2, chr1, chr0 : char
 )
 END;
 VAR
 CharCode : char;
 TrickVar : Trick;
 BEGIN
 TrickVar.long := theEvent.message;
 CharCode := TrickVar.chr0;
 IF BitAnd(theEvent.modifiers, CmdKey) = CmdKey THEN 
 {check for a menu selection}
 BEGIN
 ProcessMenu(MenuKey(CharCode));
 END
 END;

 PROCEDURE MainEventLoop;
 VAR
 Event : EventRecord;
 ProcessIt : boolean;
 x : byte;
 TheValue : Longint;
 BEGIN
 REPEAT
 SystemTask;
 ProcessIt := GetNextEvent(everyEvent, Event); 
 { get the next event in queue}
 IF ProcessIt THEN
 BEGIN
 CASE Event.what OF
 mouseDown : 
 DealWithMouseDowns(Event);
 AutoKey : 
 DealWithKeyDowns(Event);
 KeyDown : 
 DealWithKeyDowns(Event);
 OTHERWISE
 BEGIN
 END;
 END;
 END;
 UNTIL Done;
 END;

 PROCEDURE MakeMenus;{ get the menus & display them}
 VAR
 index : Integer;
 TheMenuHdle : MenuHandle;
 BEGIN
 FOR index := AppleMenuID TO MIDIMenuID DO
 BEGIN
 myMenus[index] := GetMenu(index);
 InsertMenu(myMenus[index], 0);
 END;
 AddResMenu(myMenus[AppleMenuID], ‘DRVR’);
 DrawMenuBar;
 {put a check mark on the “none” menu item by default}
 TheMenuHdle := GetMHandle(4);
 CheckItem(TheMenuHdle, 5, true);
 END;

{ Program Starts Here }
BEGIN
 Done := false;
 FlushEvents(everyEvent, 0);

 InitSCCA;
 InitSCCB;
 InitTimer(782 * 5); 
 {increment the counter every 5 milliseconds}
 StartCounter;

 MakeMenus;
 InitCursor;
 MainEventLoop;

 ResetSCCA;
 ResetSCCB;
 QuitTimer;

END.


UNIT LSPMIDI;
{Midi library available on this source code disk for LSP }
INTERFACE
 PROCEDURE InitSCCA;
 {call this once at the beginning of your application if you are going 
to use the modem port for MIDI}

 PROCEDURE TxMIDIA (TheData : integer);
 {use this procedure to transmit a byte of MIDI data through the modem 
port the MIDI byte is in the lower 8 bits of the word}

 FUNCTION RxMIDIA : LongInt;
 {use this function to get a byte of MIDI data and the counter value 
associated with that byte through the modem port the MIDI byte is in 
the lower 8 bits of the longword the upper 3 bytes of the longword contain 
the counter value when the byte arrived at the Macintosh}

 PROCEDURE MIDIThruA (Thrucode : integer);
 {this is for the MIDI thru function}
 {the Thrucode variable is as follows:}
 {0 = no MIDIThru function}
 {1 = MIDIThru on the same channel}
 {2 = MIDIThru on the opposite channel}

 PROCEDURE ResetSCCA;
 {call this procedure when your application is done if you called InitSCCA 
at the beginning of your application or the system will crash}

 PROCEDURE InitSCCB;
 {call this once at the beginning of your application if you are going 
to use the printer port for MIDI}

 PROCEDURE TxMIDIB (TheData : integer);
 {use this procedure to transmit a byte of MIDI data through the printer 
port the MIDI byte is in the lower 8 bits of the word}

 FUNCTION RxMIDIB : LongInt;
 {use this function to get a byte of MIDI data and the counter value 
associated with that byte through the printer port the MIDI byte is in 
the lower 8 bits of the longword the upper 3 bytes of the longword contain 
the counter value when the byte arrived at the Macintosh}

 PROCEDURE MIDIThruB (Thrucode : integer);
 {this is for the MIDI thru function}
 {the Thrucode variable is as follows:}
 {0 = no MIDIThru function}
 {1 = MIDIThru on the same channel}
 {2 = MIDIThru on the opposite channel}

 PROCEDURE ResetSCCB;
 {call this procedure when your application is done if you called InitSCCB 
at the beginning of your application or the system will crash}

 PROCEDURE InitTimer (TimrValue : integer);
 {call this procedure once at the beginning of your application if you 
are going to make use of time-stamping.  1 millisecond = decimal 782}

 PROCEDURE LoadTimer (TimrValue : integer);
 {call this procedure if you want to change the interval of time that 
the counter is incremented.  1 millisecond = decimal 782}

 PROCEDURE StartCounter;
 {call this procedure to set the counter value to 1}

 FUNCTION GetCounter : LongInt;
 {call this function to get the current value of the counter}

 PROCEDURE QuitTimer;
 {call this procedure when your application is done if you called InitTimer 
at the beginning of your application or the system will crash}

IMPLEMENTATION
{$A+}
 PROCEDURE InitSCCA;
 external;
 PROCEDURE TxMIDIA;
 external;
 FUNCTION RxMIDIA;
 external;
 PROCEDURE MIDIThruA;
 external;
 PROCEDURE ResetSCCA;
 external;
 PROCEDURE InitSCCB;
 external;
 PROCEDURE TxMIDIB;
 external;
 FUNCTION RxMIDIB;
 external;
 PROCEDURE MIDIThruB;
 external;
 PROCEDURE ResetSCCB;
 external;
 PROCEDURE InitTimer;
 external;
 PROCEDURE LoadTimer;
 external;
 PROCEDURE StartCounter;
 external;
 FUNCTION GetCounter;
 external;
 PROCEDURE QuitTimer;
 external;
{$A-}

END.
 
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Software Updates via MacUpdate

TinkerTool 5.3 - Expanded preference set...
TinkerTool is an application that gives you access to additional preference settings Apple has built into Mac OS X. This allows to activate hidden features in the operating system and in some of the... Read more
Audio Hijack Pro 2.11.0 - Record and enh...
Audio Hijack Pro drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio with Audio Hijack... Read more
Intermission 1.1.1 - Pause and rewind li...
Intermission allows you to pause and rewind live audio from any application on your Mac. Intermission will buffer up to 3 hours of audio, allowing users to skip through any assortment of audio... Read more
Autopano Giga 3.6 - Stitch multiple imag...
Autopano Giga allows you to stitch 2, 20, or 2,000 images. Version 3.0 integrates impressive new features that will definitely make you adopt Autopano Pro or Autopano Giga: Choose between 9... Read more
Airfoil 4.8.7 - Send audio from any app...
Airfoil allows you to send any audio to AirPort Express units, Apple TVs, and even other Macs and PCs, all in sync! It's your audio - everywhere. With Airfoil you can take audio from any... Read more
Microsoft Remote Desktop 8.0.8 - Connect...
With Microsoft Remote Desktop, you can connect to a remote PC and your work resources from almost anywhere. Experience the power of Windows with RemoteFX in a Remote Desktop client designed to help... Read more
xACT 2.30 - Audio compression toolkit. (...
xACT stands for X Aaudio Compression Toolkit, an application that encodes and decodes FLAC, SHN, Monkey’s Audio, TTA, Wavpack, and Apple Lossless files. It also can encode these formats to MP3, AAC... Read more
Firefox 31.0 - Fast, safe Web browser. (...
Firefox for Mac offers a fast, safe Web browsing experience. Browse quickly, securely, and effortlessly. With its industry-leading features, Firefox is the choice of Web development professionals... Read more
Little Snitch 3.3.3 - Alerts you to outg...
Little Snitch gives you control over your private outgoing data. Track background activityAs soon as your computer connects to the Internet, applications often have permission to send any... Read more
Thunderbird 31.0 - Email client from Moz...
As of July 2012, Thunderbird has transitioned to a new governance model, with new features being developed by the broader free software and open source community, and security fixes and improvements... Read more

Latest Forum Discussions

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New Trailer For Outcast Odyssey, A New K...
New Trailer For Outcast Odyssey, A New Kind of Card Battler Posted by Jennifer Allen on July 25th, 2014 [ permalink ] Out this Fall is a new kind of card battle game: Outcast Odyssey. | Read more »
Garfield: Survival of the Fattest Coming...
Garfield: Survival of the Fattest Coming to iOS this Fall Posted by Jennifer Allen on July 25th, 2014 [ permalink ] Who loves lasagna? Me. Also everyone’s favorite grumpy fat cat, Garfield. | Read more »
Happy Flock Review
Happy Flock Review By Andrew Fisher on July 25th, 2014 Our Rating: :: HERD IT ALL BEFOREUniversal App - Designed for iPhone and iPad Underneath the gloss of Happy Flock’s visuals is a game of very little substance. It’s cute, but... | Read more »
Square Register Updates Adds Offline Pay...
Square Register Updates Adds Offline Payments Posted by Ellis Spice on July 25th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Looking For Group – Hearthstone’s Curse...
For the first time since its release (which has thankfully been a much shorter window for iPad players than their PC counterparts), Blizzard’s wildly successful Hearthstone: Heroes of Warcraft CCG is sporting some brand new content: the single... | Read more »
Poptile Review
Poptile Review By Jennifer Allen on July 25th, 2014 Our Rating: :: SIMPLY FUNUniversal App - Designed for iPhone and iPad Simple yet a little bit glorious, Poptile is a satisfying entertaining puzzle game with oodles of the ‘one... | Read more »
Modern Combat 5: Blackout Review
Modern Combat 5: Blackout Review By Brittany Vincent on July 25th, 2014 Our Rating: :: LESS QQ, MORE PEW PEWUniversal App - Designed for iPhone and iPad The fifth entry into the blockbuster Modern Combat series is what mobile... | Read more »
Watch and Share Mobile Gameplay Videos W...
Watch and Share Mobile Gameplay Videos With Kamcord Posted by Jennifer Allen on July 25th, 2014 [ permalink ] iPhone App - Designed for the iPhone, compatible with the iPad | Read more »
THE KING OF FIGHTERS '98 (Games)
THE KING OF FIGHTERS '98 1.0 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: Series’ masterpiece “KOF ’98” finally joins the battle on iPhone! FEATURES:■ The best game balance in the “KOF”... | Read more »
LEX Goes Free For One Day In Honor of Ne...
LEX Goes Free For One Day In Honor of New Update Posted by Jennifer Allen on July 24th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »

Price Scanner via MacPrices.net

iMacs on sale for $150 off MSRP, $250 off for...
Best Buy has iMacs on sale for up to $160 off MSRP for a limited time. Choose free home shipping or free instant local store pickup (if available). Prices are valid for online orders only, in-store... Read more
Mac minis on sale for $100 off MSRP, starting...
Best Buy has Mac minis on sale for $100 off MSRP. Choose free shipping or free instant local store pickup. Prices are for online orders only, in-store prices may vary: 2.5GHz Mac mini: $499.99 2.3GHz... Read more
Global Tablet Market Grows 11% in Q2/14 Notwi...
Worldwide tablet sales grew 11.0 percent year over year in the second quarter of 2014, with shipments reaching 49.3 million units according to preliminary data from the International Data Corporation... Read more
New iPhone 6 Models to Have Staggered Release...
Digitimes’ Cage Chao and Steve Shen report that according to unnamed sources in Apple’s upstream iPhone supply chain, the new 5.5-inch iPhone will be released several months later than the new 4.7-... Read more
New iOS App Helps People Feel Good About thei...
Mobile shoppers looking for big savings at their favorite stores can turn to the Goodshop app, a new iOS app with the latest coupons and deals at more than 5,000 online stores. In addition to being a... Read more
Save on 5th generation refurbished iPod touch...
The Apple Store has Apple Certified Refurbished 5th generation iPod touches available starting at $149. Apple’s one-year warranty is included with each model, and shipping is free. Many, but not all... Read more
What Should Apple’s Next MacBook Priority Be;...
Stabley Times’ Phil Moore says that after expanding its iMac lineup with a new low end model, Apple’s next Mac hardware decision will be how it wants to approach expanding its MacBook lineup as well... Read more
ArtRage For iPhone Painting App Free During C...
ArtRage for iPhone is currently being offered for free (regularly $1.99) during Comic-Con San Diego #SDCC, July 24-27, in celebration of the upcoming ArtRage 4.5 and other 64-bit versions of the... Read more
With The Apple/IBM Alliance, Is The iPad Now...
Almost since the iPad was rolled out in 2010, and especially after Apple made a 128 GB storage configuration available in 2012, there’s been debate over whether the iPad is a serious tool for... Read more
MacBook Airs on sale starting at $799, free s...
B&H Photo has the new 2014 MacBook Airs on sale for up to $100 off MSRP for a limited time. Shipping is free, and B&H charges NY sales tax only. They also include free copies of Parallels... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Sr. Project Manager for *Apple* Campus 2 -...
…the design and construction of one building or building components of the New Apple Campus located in Cupertino, CA. They will provide project management oversight for Read more
WW Sales Program Manager, *Apple* Online St...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
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