The Deneb Board

by Eric Schwartz
from the AmiTech-Dayton Gazette, June 2008

It's not that often I have something directly Amiga-related to talk about in this newsletter, at least not as much as I used to. I have something worth mentioning today, however. Thanks in no small part to Mr. Chris Hodges, I am the proud owner of a new Deneb board for my Amiga 4000. For those who may not have heard already, Deneb is the latest, and arguably best card to give "big box" Amiga systems USB capability. Sadly, my Amiga 4000T is too bulky, heavy, and fragile for me to trust bringing the thing to a meeting, so I'll just have to give my impressions here instead.

The Deneb board itself, designed by Michael Bohmer, is rather small, at least by Amiga card standards, only about the size it needs to be to fit in a Zorro II/III slot. The fit is not completely snug, so the board may wobble a bit when seated depending on the forces applied to it. When it's properly wired in, that shouldn't be much of a problem, though the manual recommends inserting some heavy paper or other isolating material between cards if it looks likely something may touch and cause a short. On the board is an FPGA chip which houses the USB control and other logic, and several smaller chips, including the board flash ROM. There are three USB connections, pins that, with the included connectors, place two USB ports in a blanking plate out the back of the system, and one standard USB port mounted on the board itself. There is an A-1200 clock port connector, allowing the use of boards that require it, and a block of jumper pins. As shipped, the board is set in "rescue" mode, which allows access to protected areas of the flash ROM for firmware upgrades and the installation software.

It should be noted that the Deneb does not include any software on CD or floppy disk (it might be available online or through other means -- I don't know) and relies on the software tucked into the ROM on the board itself, which should be accessible when the Deneb is installed with that "rescue" jumper on. This was a bit of an issue for me, as more often than not my Amiga couldn't read the flash ROM as it was supposed to. I don't know if it was an irregularity with the board or my Amiga, but with a lot of fiddling, I was able to get into the ROM and install the included software. At this point it pays to be aware of your Amiga's hardware configuration to determine which libraries are used, notably whether you are using the board in a Zorro II (A2000 and certain setups) or Zorro III (A3000 and A4000), and whether or not it can support DMA data transfer. (As my A4000T was making full use of its built-in SCSI-2 for drives and more, I had to settle for PIO mode for the USB, which means all transfers are handled by the CPU). At this point, you would remove the jumper from the board and use it normally.

The software for the Deneb is written by Chris Hodges and, along with drivers and libraries, primarily consists of Poseidon, the USB driver stack, and Luciferin, the tool to manage the board Flash ROM contents. I'm familiar with Poseidon from the role it plays in MorphOS, and I can say it's a marvel, giving the Amiga (Pegasos, emulation, or any other supported system) seamless support for USB devices near-equal to any Windows PC or Mac -- better in some instances. With support for a wide array of storage devices, keyboards, mice, tablets, game controllers, cameras, and several other devices, it's a good bet that if it's USB and doesn't require a bunch of custom Windows software installed, you can probably use it. Poseidon allows a generous amount of customizing for your settings as well. Luciferin is the flash ROM management tool, for the 4 megabytes of flash memory on the Deneb board. This small chunk of memory allows you store programs and data meant to be usable even before the hard drive spins up. A possible example is the Poseidon libraries, which make it possible to use USB input devices before the computer is fully booted, or even boot the system from a USB storage device. One might also put "ROM tags" in the flash memory, or put a complete dump of the Kickstart ROM on the flash, to speed up the system boot and/or eliminate the "double clutch" rebooting required for Amiga as 3.5 or 3.9.

Included as initial content on the flash ROM is the Amiga-runnable version of the animation "Still Alive" by yours truly. It can be played when Luciferin is run, or downloaded and run separately. I thank Chris for the opportunity given me to have it included. To give a brief example of what this flash can offer, one of the first things you see on the first "normal" startup with everything installed is a large "DENEB" logo being burned into the screen, much in the style of early Amiga game logos. It's fun to see, but seeing it every time the Amiga starts gets tiring, so thankfully it can be removed when you update the flash ROM with Luciferin. On my Amiga, I replaced the "DENEB" intro (as opposed to having nothing) with something that plays a short musical ditty like that played by the original Amiga 1000. I mentioned earlier that my system does not seem to access the flash ROM as it should, and that is currently still the case. Luciferin reports that the Deneb board has its jumper disabling the flash ROM set when it doesn't. I'll investigate more in the future, but as I find the USB support, which is working brilliantly, the most important aspect, I will not be too concerned if I'm unable to resolve the flash ROM situation.

As it stands, the Deneb is a little pricey, as is a lot of Amiga-specific hardware, but it is truly a quality piece of work, and I'm finding it invaluable. It has made it much simpler to transfer files between the Amiga and my other systems via flash drives. At Zorro III and USB 2.0 speeds, it's quite zippy as well. I have installed a hub into a drive bay, so I have a set of USB ports in the front of the case. I have also used some flash drives to back up all the files from the Amiga's (now) modest 9 gigabyte hard drive. It's fun to see what represents years of my Amiga work and activities reduced to a few devices roughly the size of a pack of gum. If you have an Amiga that you still make use of with a free Zorro slot, and you don't have another USB card installed, you can't really go wrong with the Deneb. Even with the minor problems I've had, I recommend it wholeheartedly.