From: ProDev, Inc.

To: All Apple II programmers:

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          *        --- N E W   D E B U G G I N G   T O O L ---        *
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Announcing the ProDev Development & Debugging Tool (DDT16) for the Apple IIGS
and DDT8 for the Apple //e.


 ---- Product Description ----

The ProDev DDT is a program debugger on a peripheral card.

We combined a very extensive debugging program along with unique hardware
features to create the most powerful debugging tool available for the Apple
//e & IIGS computers. The DDT contains the debugging software in ROM, has its
own RAM and contains hardware for watching the address buss, generating
interrupts and program timing.


 ---- The Hardware Edge ----

The ProDev DDT has the normal features you find on most debuggers; Tracing,
break points, register and memory displays. What makes the DDT different is
the addition of hardware. The combination of software and hardware makes it
possible to provide features that ordinary software debuggers can not. For
example:

  The DDT does not require any memory space. This is especially important when
trying to debug programs on the Apple //e. Many times your program is too
large to allow room for a conventional debugger. You can even trace
programs that run in text RAM memory.

  The ability to do a "Break on Address" that watches every address in
real-time and interrupts the running program when the specified address
appears. This allows you to find those nasty bugs that cause part of your
program to be mysteriously overwritten. It also works as a real time
breakpoint for ROM code.

  Pressing a button to interrupt a program. Now you can see where your program
went when it got lost.

  Counting the number of clock cycles required to run your program between two
addresses you specify.


 ---- Other Goodies ----

Connect a terminal or printer to your computer and view your programs output
and the DDT output at the same time.

As you trace your program the memory location that each instruction uses is
calculated and displayed.


 ---- Main Screen ----

The following is an example of the main screen display of the DDT8.

---------------------------- top of screen ----------------------------------
                                       | M = STK REA WRI LNG BNK PG2 80S CXR
:PC=800                                |     mne mne mne rom  2  off off on
                                       |                                    
:DR                                    | KEY BRK TYP SAV TXT MIX HGR 80C ALT
A=00 X=00 Y=00 S=E0 M=09 L=0 P=--1---Z-| 93  out C02 on  on  off off off off
00/800:4C FF FB    JMP FBFF  {00FBFF   |---memory-------breakpoints----stack-
                                       |00/0024:00 @ | H             |01E2:01
:TR                                    |00/0000:4C L | I00/FBFF.0001 |01E1:E2
** BREAK **                            |00/0000:4C L |               |01E0:9A
A=00 X=00 Y=00 S=D8 M=09 L=0 P=--1---Z-|00/0000:4C L |               |01DF:79
00/FBFF:B0 EF       BCS FBF0 {-11}     |00/0000:4C L |               |01DE:00
T:                                     |00/0000:4C L |               |01DD:FC
A=00 X=00 Y=00 S=D8 M=09 L=0 P=--1---Z-|00/0000:4C L |               |01DC:53
00/FC01:A8          TAY                |00/0000:4C L |               |01DB:00
T:                                     |00/0000:4C L |               |01DA:FC
A=00 X=00 Y=00 S=D8 M=09 L=0 P=--1---Z-|00/0000:4C L |               |01D9:53
00/FC02:10 EC       BPL FBF0 {-14}     |00/0000:4C L |               |01D8:EA
T:                                     |00/0000:4C L |npt----range---|01D7:00
A=00 X=00 Y=00 S=D8 M=09 L=0 P=--1---Z-|--eff-adrs---|  00/0000.0000 |01D6:FE
00/FBF0:A4 24       LDY 24 {000024     |00/07CE:B5 5 |  00/0000.0000 |01D5:F7
T:                                     |00/07CF:A0   |  00/0000.0000 |01D4:43
A=00 X=00 Y=00 S=D8 M=09 L=0 P=--1---Z-|00/07D0:A0  <|  00/0000.0000 |01D3:30
00/FBF2:91 28       STA (28),Y {0007D0 |00/07D1:A0   |  00/0000.0000 |01D2:7D
T:                                     |00/07D2:A0   |  00/0000.0000 |01D1:F5
----------------------------bottom of screen---------------------------------

The left window displays the instructions as they are traced.

The top right window shows the state of various switches.

The "memory" window allows you to select 12 different memory locations to
monitor.

The "breakpoints" window displays the 10 most recently encountered break
points plus the one hardware break.

Next is the "stack" window which shows you the stack contents.

The "eff adrs" window displays the effective address of the next instruction
to be traced.

The "range" window allows you to enter address ranges where "No" access or
"Program only" access is permitted or a "Trace" range where real time
execution of subroutines will occur.


 ---- Ordering Information ----

The retail price for either the DDT8 for the Apple //e or the DDT16 for the
Apple IIGS is $189 + $4 for 2nd day air shipping in the 48 states.
Canadian orders shipped via UPS ground.


If you have any questions or comments please contact me at one of the
following addresses:

                     CHUCK.K           Genie

                     PRODEV            America Online

                     ProDev, Inc.      US Snail
                     PO Box 162
                     LaSalle, MI
                            48145-0162

                     (313) 241-2786    Voice

Sincerely,

Chuck Kelly
President