HYDRA Game Development Kit

The HYDRA Game Development Kit is the new, (launched in September 2006) creation of Andre LaMothe similar to the XGameStation. Like the XGameStation, HYDRA is an open system, allowing anyone to create games for it. However, being less focused on teaching electronics and more about homebrew games, the HYDRA uses a more complex and powerful CPU - the recently released Parallax Propeller processing unit, which has eight 32 bit RISC CPU's called COG's with 32KiB built in RAM and 32KiB build in ROM.

• X-Racer running on the Hydra
  X-Racer running on the Hydra
• Dodgy Kong running on the Hydra
  Dodgy Kong running on the Hydra
• Dr Hydra running on the Hydra
  Dr Hydra running on the Hydra
• Alien Invaders running on the Hydra
  Alien Invaders running on the Hydra

Image of the new HYDRA Game Development Kit

Specifications

The HYDRA Game Development Kit has the following specifications:

• Propeller CPU at 160 MIPS, 8 PIC like CPU cores each with 496 32 bit words of workspace plus a shared 32K RAM and 32K ROM
• 128K serial EEPROM
• two NES Compatible Game Ports
• one USB Programming port
• one Serial Port or second USB port
• two PS/2 Compliant Ports for Mouse and Keyboard.
• one NTSC or PAL Video Output or alternatively one VGA Video Output
• one mono Audio output
• one 20-Pin Expansion Interface connector
• one RJ-11 Peer to Peer Networking Port

The Hydra also comes with the large book (800+ pages) "Game programming for the propeller powered HYDRA", a CD with extensive software including demo games and a second book by LaMothe, a keyboard, a mouse, a NES keypad, USB and audio/video cables, a 128K "memory card", an experimenter card and a power supply.

The system can be programmed as the target of a PC-hosted IDE or through locally hosted programming languages. Tiny BASIC is included with the system, and the FORTH language is also available. Of course the Hydra can also be programmed in assembler, and in the Propeller's own built in Spin programming language.

As the video display is generated in software the capabilities of it depend on the software driver, but a typical PAL/NTSC driver would be able to generate a 256x192 screen resolution, and typically 80 to 96 colors maximum. The color resultion for the VGA display is hardwired to 64 colors maximum, and a typical resolution would be 800x600, it depends on the available display memory. A video driver uses the main 32K RAM memory which it must share with code space. With the aid of the new 512K memory expander video drivers can be written that extend the capabilities of the video generator. To aid in the display of text the Propeller chip has a complete character font in its ROM.

Memory expansion system

A 512K RAM memory expansion card, the HYDRA "XTREME 512K CARD", is available [1] and can be plugged into the expansion connector. It has two memory segments, a 64K completely random-access segment, and a 448K linear accessible segment. During boot time the memory interface can be programmed to optionally auto-increment or decrement the memory pointer for faster memory access. But the interface is based on a reprogrammable CPLD chip, so the access method can be re-programmed to suit the application, but for most applications the chosen method is optimal for speed (for the 64K segment), and utility.

The memory expansion card also has its own 128KB EEPROM on board.

External links

• official website for the HYDRA
• Discussion forum about the HYDRA at parallax.com
• More information on the HYDRA can be found at the Parallax site here and at the XGameStation site here.
• Interview of Andre LaMothe about the HYDRA at Gamasutra.