Resource centre for ZX Spectrum games
      using Manic Miner and Jet Set Willy game engines

 

 

	Previous message		Next message
	Previous in thread		Next in thread

 

 

Message: 6950

Author: rushforthian

Date: 23/11/2016

Subject: Re: Broadsoft Lifts v0.2: Hex-editor type-in

 

To confirm the above, I just loaded up a game file with the Broadsoft Lifts code implemented, with Willy's starting position set to a point which is a fatal fall distance above a lift (i.e. an Infinite Death Scenario), and ran the game super-fast on SPIN.
After going through 16 games (approx. 128 lives), the stack overflowed and caused random coloured squares to appear on the status bar. Each life lost leaves one return address (2 bytes) on the stack, and once they have accumulated to fill the entire stack (256 addresses, #5B00-#5BFF), then the attribute file (#5800-#5AFF) starts to be overwritten!
The game was still playable though. So I left it running until the random coloured squares proceeded backwards all the way up to the top of the screen, at which point the game crashed/machine reset - so presumably overwriting of the display file (#4000-#57FF) isn't so harmless...

 

 

	Previous message	Back to the Yahoo! Archive home page	Next message
	Previous in thread		Next in thread