Setting the vectors from $0314 will kill $02a6 (NTSC/PAL detection). I have no clue why? Anyone?
lda $02a6
will be 0 no matter if it's PAL or NTSC.
Docster
Viewing post in Rule Clarification plus Tips and Tricks
A good question actually... This memory location is set by KERNAL on reset $ff5b - $ff6a. So, as long as you're not touching this memory location, it should have some value. Could you share your code?
I've read everywhere not to trust $02a6 anyway.
I've used NTSC/PAL detection by TWW from this topic: https://csdb.dk/forums/?roomid=11&topicid=94459 just on the boot, before initiating an IRQ to $0314. I just needed to get back the counting of CIA 1 timer as I'm using it for randomization :).