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| Frame Grabber of the 3x product line |
| The 3x product line includes: |
| FG-39 M.2 Slot A/E, FG-38 (-II,-III) mini PCI Express, FG-37 Express-Card, FG-36(-II) PCI Express, FG-35 Low- Profile- PCI, FG-34 PCI, FG-33 CardBus and furthermore HC-37 Expresscard, HC-36 PCI Express, HC-35 PCI and HC-33 CardBus. |
| The 3x-product-line has at least three special features: |
| 1. |
All cards have frame buffers based on fast dual-port-memory or ultra fast FPGA built-in buffers. Such a solution will not have drop-outs in data streams often accepted with low-cost multimedia grabbers |
- No image data is lost, when another processes requires priority in getting computing power.
- Image data can be transferred with a lot more independence from the required transfer speed. A real-time API allows image data transfers with very low latency.
- For stereo applications two or more cards can capture frames from their corresponding camera simultaneously.
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| 2. |
All cards have a common driver interface, so one program can be written with one type of card, where the target system uses a different card. It is also possible to switch between operating systems (e.g. Windows 11 to XP). Dos and OS/2 are still supported for some of the cards due to long term agreements. |
- No software redesign required, when there are hardware changes
- No software redesign required, when the operating system will be changed.
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| 3. |
All cards have high productivity busmastering transfers and a special built-in test-mode. The system can validate the frame grabber functionality and measure transfer speeds. |
- The Busmastering transfer includes, but is not limited to scatter gather DMA.
- FG-39, FG-38-III and FG-37 have six DMA channels with independent access to the same physical memory.
- Image transfer functions can be written to work in real mode, protected mode and in virtual Dos-machine.
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Scatter Gather DMA is just the result of lazy OS programmers. Instead of providing continuous physical memory of the requested size they send a whole list of physical selector addresses to the hardware.
Of course the FG3x cards have DMAs that can handle such lists too, but HaSoTec device drivers rather take continuous physical memory for its buffers.
This works from simplest DOS versions up to OS versions where even the manufacturer cannot explain the delays anymore.
Knowing where the physical memory of frame buffers is located has several advantages for additional hardware and real-time software.
With memory requests each memory selector needs management.
This produces inacceptable management overhead:
Think about a huge memory broken in to 4KByte pieces spread over the whole RAM with a few thousand selectors to be declared non moveable non cacheable.
This is not the way to efficiency.
It is closer to the bad story of the BMP file format, where lines of the image are placed in the data structure in reverse order.
This has lost performance and programming time for more than 10 years and, of course, no one feels responsible for such a fundamental mistake.
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