Catalogue of Arcade Emulation Software - the Absolute Reference

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Zoo Keeper (set 1)

0.29 [John Butler, Ed. Mueller]


- The first time you run the game, it will ask the location. You can change the name using F5/F6 and F2, then F1 to proceed through all the configuration screens, or just reset (F3).

- Keep F2 pressed to enter test mode, then F1 to advance to the next test.

- There are no dipswitches, press F1 to enter the service mode, then F1=Next screen, F2=Next line, F5=Up and F6=Down.


- Every time you start the emulation, you get a free credit. This is due to the 68705 based protection.


- 0.37b16: Changed M6802 CPU3 clock speed to 921600 Hz, M68705 MCU to 1MHz and set palettesize from 256 to 1024 colors.

- 0.35b4: Fixed cpu1 rom ($8000).

- 28th February 1999: Nicola fixed Zoo Keepers from crashing on the first bonus life stage.

- 0.35b6: Replaced M6803 CPU3 with M6802 and M6805 CPU4 with M68705.

- 0.35b3: Nicola Salmoria added clone Zoo Keeper (set 2) and properly emulated the 68705 protection in The Electric Yo-Yo, Kram, Space Dungeon and Zoo Keeper. Added M6805 (2MHz) CPU4. Renamed (zookeepa) to (zookeep3).

- 0.33b7: Nicola Salmoria added clone Zoo Keeper (set 2).

- 0.30: Changed description to 'Zoo Keeper'.

- 0.29: Added Zookeeper (Taito 1982). John Butler and Ed. Mueller did a early attempt at a Zookeeper driver, based on the Qix one, which unfortunately doesn't work yet. ZooKeeper uses the same hardware as Qix (two 6809 CPUs). One CPU for data and sound and the other for video. Communication between the two CPUs is done using a 4K RAM space at $0000 which both CPUs have direct access. FIRQs (fast interrupts) are generated by each CPU to interrupt the other at specific times. The coin door switches and player controls are connected to the CPUs by Mototola 6821 PIAs. These devices are memory mapped as shown below. The screen is 256x256 with eight bit pixels (64K). The screen is divided into two halves each half mapped by the video CPU at $0000-$7FFF. The high order bit of the address latch at $9402 specifies which half of the screen is being accessed. Timing is critical in the hardware. The data CPU must have an interrupt signal generated externally at the right frequency to make the game play correctly. The address latch works as follows. When the video CPU accesses $9400, the screen address is computed by using the values at $9402 (high byte) and $9403 (low byte) to get a value between $0000-$FFFF. The value at that location is either returned or written. The scan line at $9800 on the video CPU records where the scan line is on the display (0-255). Several places in the ROM code wait until the scan line reaches zero before continuing.

Other Emulators:

* HiVE

Recommended Games:

Noah's Ark


Video Vince and the Game Factory

Romset: 78 kb / 20 files / 43.8 zip