CompuServe Thread

#DC1tv comments

2 messages in this thread
#3965From: Thomas H. GiebinkMar 22, 1995 10:16 AM
A copy of comments to from MIRO that I hope will prompt some conversation and solutions here: Thank you for your comments Rainer (MIRO), >>>probably HDSPEED gives no correct values because of the activated cache options for your harddisk. We experienced it very difficult to get 100% results with actual SCSI controllers because of the poor Windows 3.11 support of most of these devices. The best capture and playback results will be accessed with Enhanced-IDE controllers and the corresponding HDs.<<<< Alot of us Miro users are also SCSI based so I think that a well-laid out plan for optimizing SCSI systems would enhance the loyalty of your customers considerably. Certainly it would me. This may not be a hard drive problem!! When I work with FIXED MJEPG quality (which should be the best indicator of the what the system is capable of, right??) I get the same results wether I digitize to RAM or to Hard Disk. In both cases the maximum quality with no frame drop is 87% (I'm digitizing from Hi-8, a Y/C signal). I have seen MACs do much better. Are Pentiums limited?? Or, is it possible that DMA rate is too small or slow (I do not understand this very well… llet alone how to vary it)?? Does the DC1tv have a memory cache that can be increased?? Is this a limitation of your MJEPG digitizing chip?? !! Is there a way to make sure that the data is passing through the PC itself with no bottlenecks?? !! Some specific questions: >In the place where you set the video format (Premiere / Movie Capture / Recording Options / Video Format /… I select> 320×240; 0 cropping; image format: MJPEG; mjpeg options: automatic quality control, data rate= 450, mjpeg start quality= 95%. The Question: What does data rate mean?? What effect does it have?? There was an article in NEW MEDIA (November) which reviewed all the video cards and rated Miro at the top ( I bought the card based on that). They make recommendationsfor how to tune the capture cards. I would very much appreciate your comments and help in implenting them (The quoates form the article begin with ** ; My questions to you with ?? **ennable 32 bit file, BUT NOT 32 BIT DISK, access** ?? why not 32 bit disk as well, I've tired that and it seems faster with 32 bit disk too?? **Use Smartdrv carefully (/R) or turn it off. Turn off double buffering** ??why turn off double buffering?? **Optimize your SCSI BIOS, set sync negotiation and the highest DMA transfer rate that doesn't crash your computer** ??As I said I'm from the Amiga. I'm completely lost here. Can you tell me how to do this?? **Shadow the ROM BIOS of your grphics display and SCSI adapter to RAM, but watch out for conflicts with your capture card memory exclusion.** ??Again, I'm completely lost here. Can you tell me how to do this?? **Get rid of TSRs that may cause interrupts. Creat a special boot sequence for video work.** ??Again, I'm completely lost here. Can you tell me how to do this?? **Once you've optimized your harware setup for video, run MEMMAKER to load devices into upper memory blocks and free up conventional memory.** ??I know how to do this?? **Use EMM386.exe with nNOEMS, and carfully set memory exclusions required by your video card. X=D000 is often best. Look for conflicts with the SCSI and graphics BIOS, typically C000.** ??I have done this?? **IRQ conflicts are the most common problems in your system. Best IRQs for capture cards: 10,12,15.** ??I have done this?? **In Pentium machines, go into the motherboard BIOS and disable the same memory areas there to prevent plug and play cards from grabbing them. Also, mark the IRQs for your video cards as USED or ISA.** ??I don't have any "plug and play" cards so would prefer not to mess around with the motherboard BIOS?? ??How do I "mark the IRQs as used?? **Don't use the modeswitch feature on advanced graphics cards that let you change resolution without rebooting your Windows. It eats memory.** ??I use an ATI card (PCI) with 2mg ram. I would love to be able to see 30frames/sec on the computer screen. Would the ATI do that with 4mg?? Or do I need a special card from Miro?? **Turn off energy sonservation features in Green PCs.** ??I have a green PC… I need to look at their documentation to see how to disable that?? I plan to upgrade to a 60field/sec 640×480 card as soon as I can get reliable testimony as to the quality of the various cards. I have heard that Miro is coming out with a DC2tv card which will have those characteristics. Is that true? How soon? I've spoken with a few companies here in the U.S. which are coming out with cards in May/June. Those will be best adapted for SCSI. Will your new card be IDE based or SCSI?? To do the work I want to do I need the size and speed of SCSI fast/wide. Micropolis seems the way to go… but I am waiting to see. IDE seems too limited in the long run. The Miro card is well designed but I want & need higher quality video output (By the way, I came to PCs from the Amiga, a much loved machine, on that platform there is VLAB MOTION, also a German Co. The output from that card is superb! at roughly the same cost as Miro's card… it is a full 640×480 60 fields/sec). I would very much like to clear up the quality limitation with my machine. This seems to be an issue for Miro to address… Its hard to think of going to an even more data intensive setup if my PC can't handle this one currently. I also can't believe that my system is so limited… since word from others is that they get much higher qualtiy video out of P90s Please reply, Thank you for your help, Tom
#4083From: Jim GastMar 25, 1995 11:37 AM
I wish I could answer your questions, but I have an even worse problem than you. I have a Gateway 2000 P5-90. It is a PCI bus computer which wants to help me out by optimizing a few too many things. Your miro DC1-TV card has 16K of RAM (Random Access Memory that is readable and writable). But my PCI bus pentium gets a little extra speed by "shadowing" all memory addresses from the ISA bus into fast RAM on the motherboard. This is OK for ROM on ISA cards, but in my case it prevents the processor from seeing any change in miro's RAM. Since you don't have that problem, you are safely beyond the advice to eXclude this memory in EMM386.EXE. You are also past the point where you have to worry about "preventing plug and play cards from grabbing these memory addresses". If those were your problems, I don't think the symptom would have been mere slowness. I'm not that far yet. EVERYTHING I try gets "miroVIDEO DC1: Memory not readable at given address." I added X=CC00-CFFF to my EMM386, I added EMMExclude = CC00-CFFF" to my [386Enh] section in SYSTEM.INI. At bootstrap time, I went into Advanced BIOS setup, under Plug and Play and set the ISA Shared Memory Size to 16K starting at CC00. I have nothing else using I/O 350-35F, IRQ 10 or DMA 7. My sound card is an ENSONIQ soundscape. The other boards in the machine are an Adaptec 1540CF SCSI controller and an ATI Mach 64 SVGA adapter. I even tried changing the comfiguration mode for the ISA to ICU (in the Plug and Play section of the Advanced BIOS setup). Nothing has had any effect at all. The symptom has been absolutely constant: "Memory not readable at given address". Thanks in advance for any help anyone can give me! Jim Gast