Flying Shark

[+InsaneMultitasker]

@Asmusr

I've been applying my updated Geneve routines and loader to Flying Shark so that I can release the changes.  Alas, the game now never makes it past the title screen and the music never starts.  I thought the problem was in my keyboard routine, but Pinball is working with the same code. While debugging I came across four places where "shark.a99" is setting the workspace to 0 with "LWPI 0".  Maybe this code isn't used? Sharing for your thoughts.  See screenshots. 

 

 

[Asmusr]

That instruction is modified to restore the WS. 

[+InsaneMultitasker]

Oh, sure enough, with fresh eyes I now see the MOV instruction following the STWP statement.  Thank you!

[+InsaneMultitasker]

With much appreciation to @mizapf, we were able to track down the root cause of my Geneve conversion problems.

 

The first problem was one of forgetfulness: I had modified the key EQUates to represent their ASCII equivalents for use with my 2022 loader.  The 2023 updated loader now uses the CRU-based row/column values, which it translates to XT state table values as needed.  The wrong values had the unintended consequence of passing all keyboard requests to the 9901 CRU-based joystick routine, which then incorrectly tested CRU address 0 (9901 mode setting), and returned NEQ for all key tests. 

 

My error was compounded by a surprise: the ROM image that I am using contains all 0x000 in bank >6078.  Together with the first problem, Flying Shark thought the "M" key was -always- pressed, so it dutifully passed control to bank >6078 and a host of 0x0000 instructions that the Geneve did not like.

 

I am fairly certain that I downloaded the ROM at the same time as the source files, back in June 2022.  I'll review what I have locally either tonight or tomorrow.  I confirmed that my earlier release crashes if 'M' is pressed.

[+mizapf]

16 hours ago, InsaneMultitasker said:

With much appreciation to @mizapf

... and, of course, the Geneve emulation in MAME and its debugger. 🙂