noob questions about the hydra

ThePenguinMaster

hey guys.. i dont knowe to much about the hydra kit and im wondering about a few things... first off.. i heard that the hydra is properrer based. so is it the same chip with some extra support hardware? also, if you wright a program on the hydra, will it run on a properrer? or is there a big difference in the structure and the boot loader?

Mike Green

The Hydra consists of a Propeller chip and its support parts (power regulators, EEPROM, crystal, reset button). It has some of the same I/O as the other Propeller boards like video output, VGA output, PS/2 keyboard and mouse input, but some of this I/O is connected differently from other Propeller boards. In some cases, different I/O pins are used. In other cases, slightly different circuitry is used. The game controller and I/O expansion card interfaces are unique to the Hydra. They're not very complicated, but they only exist on the Hydra.

Any Hydra program will not work directly on a non-Hydra board. If you don't use the game controller or expansion card, you will need to change a few constants in most programs and recompile to get the program to work on a non-Hydra board. The PS/2 keyboard and mouse drivers are incompatible between the Hydra and non-Hydra boards (they're hardware specific), but you can usually substitute the non-Hydra driver source for the Hydra driver source and recompile and it will work. There are some programs (like FemtoBasic) that are already compiled for different boards and include binary files for the Hydra, Demo Board, and Protoboard as well as versions for a TV display and a VGA display.

ThePenguinMaster

ok so the only limitation is that the demo board is setup different? as for the prop controller itself, there is no difference? i was wondering this because i wanted to work more with graphics and loading graphics from a remote location (maybe like you do with the hydra and the game cards). and i was thinking i could use the book for basic instructions and examples on how thease things work on the propeller, of coarse noting the differences in the hardware external to the prop chip. i saw a post where someone overlayed two images and displayed it on a tv, what im wondering is if the hydra dose this without much trouble, the prop should be able to do this too. i need to make a gui eventually and i wanted to see how this works out.. so maybe ill buy the book..

AndreL

Also, the hydra's expansion port is very useful. You can hot swap new programs into the slot as well as plug in the new 512K SRAM expansion which is unique to the HYDRA. Thus with the hydra you can have a couple memory cards with different programs, simply pull one out put another in you are programming in basic, pull that out, put another in, you are playing breakout. So, you don't need the PC host as much if you want to load different programs. On the hydra page there are a number of downloadable chapters as well, so check those out.

Andre'

Post Edited (AndreL) : 7/19/2007 1:00:12 AM GMT

Mike Green

The Hydra happens to use the DIP package while the Demo Board uses a smaller surface mount package.

The chip inside the package is the same.

One more difference is that the Hydra comes with a 128KByte EEPROM while the Demo Board only has a 32KByte EEPROM.· Very few programs make any use of EEPROM above 32K and the Propeller Tool won't load programs above 32K, so this difference would not be important to most people.

Keebler

Mike Green said...

One more difference is that the Hydra comes with a 128KByte EEPROM while the Demo Board only has a 32KByte EEPROM. Very few programs make any use of EEPROM above 32K and the Propeller Tool won't load programs above 32K, so this difference would not be important to most people.

:[noparse]:fanfare:[/noparse]: But now there's Hydra Asset Manager for all your > 32K needs [noparse]:)[/noparse]

Rich