02846: ballbomb: Undumped cloud ROM appears to be the same cloud ROM used in polaris.

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
02846	Graphics	Minor	Always	Jan 19, 2009, 07:36	Jan 21, 2009, 22:43

Tester	chowell	View Status	Public	Platform	MAMEUI
Assigned To		Resolution	Suspended	OS	Windows XP/Vista 32-bit
Status [?]	Closed			Driver	midw8080/8080bw.cpp
Version	0.129	Fixed in Version		Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	02846: ballbomb: Undumped cloud ROM appears to be the same cloud ROM used in polaris.
Description	Balloon Bomber's cloud graphics are currently listed as missing. However, the ROM part number "mb7052.2c" and ROM size (256 locations) appear to be identical to those for the cloud ROMs used in polaris and polarisa. Also the clouds look similar in screen images from flyers for Polaris and Balloon Bomber, though the images are small and it's hard to be sure. It seems that Taito may have used the same part for both games, and thus the same ROM image should be used for ballbomb. Of course, this would require actually implementing the cloud graphics in ballbomb, since they are currently unimplemented. Presumably the circuits were similar and the code from polaris can be used.
Steps To Reproduce
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	ballbomb

Attached Files

No.03617 chowell Developer Jan 21, 2009, 22:43	Please close this bug. I now think I was mistaken. When I pointed out that the ROM part numbers were identical, I thought that they were Taito internal part numbers for a specific ROM mask. Only later did it occur to me that they might be generic. In fact, "mb7052.2c" is a combination of the part number for a Fujitsu MB7052 256 x 4-bit PROM and its location at coordinate 2C on the game PCB. These could easily be the same for both games with the ROMs holding different data. The supposed similarity of the clouds in flyer screen images for the two games is debatable; by itself, that's not enough reason for a bug.

No.03617

chowell

Developer

Jan 21, 2009, 22:43

Please close this bug. I now think I was mistaken.

When I pointed out that the ROM part numbers were identical, I thought that they were Taito internal part numbers for a specific ROM mask. Only later did it occur to me that they might be generic. In fact, "mb7052.2c" is a combination of the part number for a Fujitsu MB7052 256 x 4-bit PROM and its location at coordinate 2C on the game PCB. These could easily be the same for both games with the ROMs holding different data.

The supposed similarity of the clouds in flyer screen images for the two games is debatable; by itself, that's not enough reason for a bug.