MAMEWorld Forums - Programming - Need ROM_LOAD_NIB_HIGH and ROM_LOAD16

Hi all.

I'm currently trying to add to Mame a new game called "Space Ship" from Sega.
Game is a clone of Cinematronic's Space Wars.
Probably Sega bought a license to Cinematronic.
As far as I known, I own the only known cabinet.
I finished to dump all bipolar PROMs today.
Check this message.

PCB is extremely closed to a CCPU with some differences in :
- one CCPU PROM content (it does not affect CCPU behavior)
- chips used to store program code : SEGA uses 8 chips of 1024 x 4 bits (Cinematronic uses 2 chips of 8 bits).

There are also some minor (but real) differences in game. play.

Here is my question :
CCPU uses a 16 bits wide data bus.
For example, in spacewar, Cinematrinics uses two 8 bits-wide chips.
In spacewar's ROM settings, the ROM_LOAD16_BYTE macro is used twice so that 1 file is loaded at even addresses and an other file is loaded at odd addresses.

But for Space Ship, for the same kind of result, Sega uses eight 4 bits-wide chips.
It means that :
- high nibble of even bytes are stored in file #1
- low nibble of even bytes are stored in file #2
- high nibble of odd bytes are stored in file #3
- low nibble of odd bytes are stored in file #4
There are file #5 to file #8 used for the 2nd part of the address space.

How can I used a mix of ROM_LOAD_NIB_HIGH and ROM_LOAD16_BYTE ?
What I need is :
- "ROM_NIBBLE | ROM_SHIFT_NIBBLE_HI | ROM_SKIP(1)"
- "ROM_NIBBLE | ROM_SHIFT_NIBBLE_LO | ROM_SKIP(1)"

There is no "ROM_LOAD_xxxx" macro that fits Sega's design for memory layout.

What should I do ?
a) use directly macro ROMX_LOAD() with the correct arguments ?
b) create 2 new macros in romload.h ?
c) merge PROM dumps to have 8 bits dumps (but it's not accurate and does not match the real hardware)

Thanks for your help.

Regards,

Fab