Tested today the rom version on the Multicartridge, and works flawlessly!
I'm going to surprise some friends of mine this weekend, hehe
Flagon Bird
Re: Flagon Bird
That's great news! Hope you have fun with it.robcfg wrote:Tested today the rom version on the Multicartridge, and works flawlessly!
BTW. Spotted a nice mention here http://www.retrovideogamer.co.uk/index.php?topic=4293.0
Re: Flagon Bird
The flying brick with a deathwish (my best score is a lowly eight) doesn't like it when a DASM/DEMON cartridge is inserted in the computer. I've verified this on real hardware, as well as with XRoar, so I'm wondering if Flagon Bird uses any of the addresses between $600 and $900, as this is the address space used and/or reserved by DEMON.
Re: Flagon Bird
Yes, $600 is the base address of the screen. I can move it if you'd like?Alastair wrote:I'm wondering if Flagon Bird uses any of the addresses between $600 and $900, as this is the address space used and/or reserved by DEMON
Re: Flagon Bird
For some reason (bug?) DEMON always sets bit 2 of $FF03 (IRQ on LO to HI instead of the default IRQ on HI to LO) when the computer is first switched on or cold reset. Enter POKE65283,PEEK(65283)AND253 to clear bit 2 before EXECing the game.
Re: Flagon Bird
Thanks, this works. If it is a bug did Compusense ever correct it? (The release version I have is 1.1.6, does a later version of DEMON exist?)zephyr wrote:For some reason (bug?) DEMON always sets bit 2 of $FF03 (IRQ on LO to HI instead of the default IRQ on HI to LO) when the computer is first switched on or cold reset. Enter POKE65283,PEEK(65283)AND253 to clear bit 2 before EXECing the game.
Re: Flagon Bird
I don't know, but it can easily corrected by changing the value at $C042 from 3 to 1.Alastair wrote:If it is a bug did Compusense ever correct it?
@Bosco: Adding the following code to the start of your game will prevent these problems by making sure that that the hardware is always correctly set up and IRQ enabled. It will also restart the game if the reset button is pressed.
Code: Select all
LDD #$557E * Default EXEC address
LDX #RESET
STA <$71
STX <$72
LDX #FIRQ
STB $010F
STX $0110
JMP [$FFFE]
FIRQ PSHS A
LDA $FF23
ANDA #$FE
STA $FF23
LDA $FF22
PULS A
RTI
RESET NOP
ORCC #$50
LDS #$02D8 * Cartridge ROM entry address
LDA $FF03
ORA #$01
STA $FF03
ANDCC #$EF
Last edited by zephyr on Tue Jul 08, 2014 9:32 am, edited 9 times in total.
Re: Flagon Bird
Thanks zephyr, sounds like a great idea.
I'll add your code to v1.1.
BTW. I'm assuming this is CoCo safe?
I'll add your code to v1.1.
BTW. I'm assuming this is CoCo safe?
Re: Flagon Bird
Yes. Safe for all CoCo models.Bosco wrote:BTW. I'm assuming this is CoCo safe?
Re: Flagon Bird
You could make your game compatible with all 16K CoCo 1/2 models if you changed the ORG address from $4000 to $1E00.