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Irq dma err

IRQ, DMA, and other Computer Creatures

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IRQ's (Interrupt Request) LinesIRQ's are hotlines to the main computer (CPU) that allow devices connected to the computer to signal the CPU that they need immediate attention. If you're a Batman fan, think of IRQ's as the Batphone - getting his attention immediately. 
Not all devices require IRQ lines, which is good news because in modern (post IBM XT) computers, we only have 16 of them. Of those, 3 are already dedicated to the main system board itself - the system timer, keyboard, and memory parity error signal. That leaves only 13 for all the other devices connected to your computer. This is why IRQ conflicts are probably the #1 problem faced by computer users when they add hardware to their computer.  


 

Its a general rule for ISA-type systems (the standard computer architecture used in most IBM compatible systems) that IRQ lines CANNOT by shared with multiple devices except under special circumstances. For this reason, a good understanding of what IRQ's are assigned to what devices is essential in avoiding conflicts. The table below is a general outline for standard IRQ assignments.IRQ DEVICE USED in AT, 386, 486, and Pentium Computers
0 System Timer
1 Keyboard Controller
2 Tied to IRQs 8-15
3 COM 2
4 COM 1
5 LPT2 or Sound Card
6 Floppy Diskette Controller
7 LPT 1
8 Real Time Clock
9 Substitutes for IRQ 2
10 Not Assigned
11 Not Assigned
12 PS/2 Mouse Port
13 NPU (Numerical Processing Unit)
14 Primary Hard Disk Controller
15 Secondary Hard Disk Controller


Depending on the computer's configuration, add-in devices such as SCSI controllers, sound cards, modems, cd-roms, etc. will want an IRQ line that is already used by another device, and thus we have what is commonly referred to as an IRQ Conflict. 

The most common IRQ conflicts seem to be between two COM ports, generally a mouse and modem conflict that ends up freezing the mouse whenever the modem is activated. The table below explains each IRQ and the most common devices each may use.

Posted on Oct 18, 2008

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IC VERIFY CREDIR CARD SOFTWARE WONT DIAL OUT AFTER SWAPING HD TO A NE PC. EXTERNAL MODEM WORKS FINE, SETTINGS ON ICVERIFY POINTS TO MODEM COM PORT. SOFTWARE WILL NOT DIAL OUT. aNY HELP?


Ok,

There's really only a few reasons this would fail beyond the COM settings. First, if the computer you're using has actual serial ports on the board and you're using a USB modem or if there are more than one serial ports it's possible you have either got the wrong COM assigned or that you have more than one trying to use COM 1. This will not cause conflicts with newer USB based devices but can when using actual UART chips on the motherboard or a mix of USB and UARTs.

Go into device manager and check for additional ports. Disable all COM ports except the actual modem and try again. If it still fails, check for DMA and IRQ conflicts. Do this by going into Start>All Programs>Accessories>System Tools>System Information.

Once open navigate to System Summary>Hardware Resources>Conflicts and Sharing.

Check for any conflicts with COM 1 and it's related DMA settings or anything sharing an IRQ with the modem. If you find any devices conflicting or sharing IRQ or DMA with the modem either disable the device or go into device manager, double click the offending device, click onto the resources page and find an alternate configuration that uses different IRQ/DMA that won't conflict. This will require a reboot for most devices.

Sorry my answer would be faster but I'm shaking almost a decade worth of dust and cobwebs out of my brain that have built up since the last time I even used a modem for ICVerify.

Hope this helps, lemme know how you make out,

chris

Dec 23, 2010 | Computers & Internet

1 Answer

On linux centos it doesn work


The CT4170 SoundBlaster "Vibra" cards are old 16-bit ISA PnP cards, and were not detected at install by Linux kernels 2.16.15-27. You need to get the "isapnptools" package from the Fedora or CentOS sites, and do the following:
2. Install isapnptools using dpkg -i path-to-downloaded file .
3. Create and edit file /etc/isapnp.conf and put the following contents in it:
(READPORT 0x0273)
(ISOLATE PRESERVE)
(IDENTIFY *)
(VERBOSITY 2)
(CONFLICT (IO FATAL)(IRQ FATAL)(DMA FATAL)(MEM FATAL)) # or WARNING (CONFIGURE CTL00f4/-1 (LD 0
(INT 0 (IRQ 5 (MODE +E)))
(DMA 0 (CHANNEL 0))
(DMA 1 (CHANNEL 1))
(IO 0 (SIZE 16) (BASE 0x0240))
(IO 1 (SIZE 2) (BASE 0x0300))
(IO 2 (SIZE 4) (BASE 0x0388))
(NAME "CTL00f4/-1[0]{Audio }")
(ACT Y)
))
(WAITFORKEY)
4. Run "isapnp /etc/isapnp.conf". If it reports errors, you must change configuration above (it is suited to my setup). Try "pnpdump -c" and put its output in /etc/isapnp.conf file. If it does not help, you must find the correct configuration manually, for example change port to 0x220. For full list of possible values run pnpdump. Note that if you change the configuration, you must change options for modprobe below.
5. Create and edit file /etc/modprobe.d/sbvibra and put the following options in it:
alias snd-card-0 snd_sb16
options snd_sb16 port=0x240 irq=5 dma8=0 dma16=1 isapnp=0
6. Run "update-modules"
7. Run "modprobe snd-card-0". If it works OK (check if "ls -l /dev/dsp" shows that file is present), perform the steps below to make setup permanent:
8. Append following line to /etc/modules:
snd-card-0
8. Go to system configuration (in GUI) and choose "Services". Enable "isapnp" service and tick option to start it at boot.
Hope this helps :)

Ted

May 23, 2009 | Creative Labs CT4170 Sound Card

1 Answer

Camera problem


The camera driver cannot use an appropriate IRQ or DMA.

To fix:
1. Goto Start, Run and type devmgmt.msc
2. In the right side of the window, you will see some YELLOW and RED flags. Highlight (click once) on each of these and hit DEL
3. Exit
4. Reboot

When it reboots, WIN will re-arrange IRQ and DMA for all devices. It should now work... If not, do it all again. Yo may have to also do this if you Patch or install Service Packs. Windows is like that.

Cheers!


Mar 26, 2009 | Acer Aspire 4530-5889 Notebook PC

1 Answer

Ingram Micro TFT-LCD monitor fault.. When my computer boots up the resolution is correct 1152 by 864 pixels but after a few seconds the resolution reverts back to 640x480 and I have to go in to screen...


CHECK THE DRIVERS FOR THE SYSTEM, THE DRIVERS CAN BE CORRUPTED, OR MISSING PARTS OF THE PROGRAM.

THE BATTERY ON THE MOTHERBOARD IS FAILING

MONITOR IS STARTING TO FAIL

VIDEO CARD ERRORING OR AND THE VIDEO CARD IS HAVING IRQ AND DMA CONFLICKS
TRY TO USE THE SAME IRQ IS OR ANOTHER DEVICE WANT TO USE AND IT IS RESETTING THE MONITOR EVERY TIME

ROD

Feb 21, 2009 | Ingram GeForce 2MX (32 MB) Graphic Card

1 Answer

9200SE agp Card


THIS MAYBE THE PROBLEM, IRQ AND DMA CONFLICKS, I KNOW IT SOUND OUT THERE, BUT SOMETHING ELSE IN THE COMPUTER WANTS THAT SAME IRQ AND DMA CHANNEL IN THE COMPUTER, THE DMA MAYBE A MEMORY ADDRESS AND YOU CANNOT CHANGE THAT BECAUSE IT IS SETUP TO THE THAT HAS A HIGHER COMPONET ADDRESSING, WHICH EVERY PEACE OF EQUIPMENT THAT WORKS IN SEQUANCE, LIKE CPU, MEMORY, IO, KB, PORTS, VIDEO,
ADRESS THAN ARE SUPPOSE TO HAVE UNLIMIT AMOUNT OF IRQ AND DMA, THIS MAYBE HARDWARE COMPATIBILITY PROBLEM THAN A SOFTWARE ISSUE.

ROD

Feb 11, 2009 | ATI RADEON 9200SE, Graphic Card

1 Answer

Screen shuts off


Conflict of DMA or IRQ one has to over-rule or both give up hope. end result is nothing. Sugest you try another IRQ or DMA, I dot know, but there is a confliict of intrest.

Feb 09, 2009 | Dell Inspiron 1100 Notebook

1 Answer

Memory card locked


you are have irq and dma conflicks

you memory wants to share the same memory address with some other device inthe computer system and that memory address cannot be moved.

rod

Feb 01, 2009 | Kingston flash memory card - 256 MB -...

1 Answer

No sound


The video card has nothing to do with this unless they are sharing the same dma/irq settings, try changing the sound card to irq5

Aug 10, 2008 | Nvidia Geforce FX 5200 Graphic Card

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Printer Driver and Manual for a Canon MultiPass C3000


yedya gandichya driver cd sambhalta yet nahi tar printer kashala gandit ghalayla ghetlas

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