So that all Asterock owners can use it, I've uploaded the Asterock Freeplay ROM hack in the message.
The hack is just two changed bytes on ROM file SIDAMAS.2
Following it the info as posted by Steve on the Vector list:
Below is the Asterock free play patch which required only the sidamas.2 rom be modified for the hack to work. The code has been successfully tested in mame with a handful of plays and it is functional. YMMV on actual hardware so let me know if you encounter an issue and I will take a second look.
The sidamas.2 rom is the only rom which requires modification and is mapped between 0x6800 and 0x6BFF on the Asterock hardware.
Old Code:
0x68ED LDY $6F ;// credit count is stored at 0x006F
New Code:
0x68ED LDY #$02 ;// load y register with value of 2 credits
Using your favorite hex editor, modify the sidamas.2 file beginning at offset 0x00ED and replace the following two bytes:
0x00ED 0xA4 ==> 0xA0
0x00EE 0x6F ==> 0x02
Fluke 9010 checksums for in circuit verification
Original sidamas.2 rom = 0x388F
Patched sidamas.2.freeplay rom = 0x0DE3
