|
Yes. Use shifting (Flip-Flops). You will need to add an external power-supply, though, but that should not be much of a problem. I believe there actually is an article on that topic just here on CP.
Otherwise, search for "Blinkenlights" and explore from there. Blinkenlights is a light matrix display controlled by a PC. There are some implementations using LEDs instead of the floodlights, so you might even find a working solution for your project. I assume its about creating a marquee of some sort 
|
|
|
|
|
A simpler solution would be to utilize the control port as well as the data port.
|
|
|
|
|
is it possible?? please rbuchana, tell me how??!!
|
|
|
|
|
Well how are you writing the parallel port? Either using Inpout32.dll or _inp/_outp depending on your operating system. Either way your writing to an address (maybe 0x378). The control port is 0x02 more than the parallel port address.
So if your parallel port address is 0x378 then...
status address: 0x379,
control address: 0x37A.
Utilizing the control port will give you 4 extra output ports.
FYI some of the control ports are hardware inverted.
If you need more than 12 outputs, you may need to do like previously suggested and add some extra external logic.
|
|
|
|
|
thank you rbuchana , u're gr8
|
|
|
|
|
thanx Sebastian!i'll look for that "Blinkenlights". actually it's not a marquee that im doing, it's about creating a digital counter on a 7-segment display that i cant light more than one full digit "8".
to define recurrsion, we must first define recurrsion!
|
|
|
|
|
hello guys, does anyone know where to get an affordable volumetric 3D projector that can display floating holograms in the air??
check this cool sample
ps. u need google video player to view the sample.
|
|
|
|
|
Hi ¤ Muammar ¤,
I'd bet if you Googled, one of the sponsored links would be selling what you're after.
Jeff
|
|
|
|
|
thanx Jeff
|
|
|
|
|
hi everyone, i have two relays that read as:
(RadioShack)
Coil rating of 5VDC
90 mA
55 ohms
SPDT 1A at 125VAC
(FANGKE)
10A/28VDC
5A/220VAC
DC 5V
please advice why cant i trigger them using the 5v from the LPT port
thanx in advance.
|
|
|
|
|
Have you used a multimeter to confirm you're providing the amount of current and voltage that the relay requires to switch over? IIRC the LPT port is a relatively low power interface, it might not be able to provide sufficient power to work the relay.
--
Rules of thumb should not be taken for the whole hand.
|
|
|
|
|
you're right dan! i thought LPT is always providing 5v. here's what i got
3.34 DCV
46 mA
i just found this relay on radio shack, do you think it will work with the amount of current i have??
Maximum switching power of 10 (Watt/VA)
Maximum switching voltage of 60 VDC, 120VAC
Maximum switching current of 0.5 A
Maximum initial contact resistance of 150m ohms
thank you dan!
|
|
|
|
|
|
¤ Muammar ¤ wrote: Coil rating of 5VDC
90 mA
The LPT port can't produce 90mA at 5V. The
spec[^] requires only 14mA drive capacity at 2.4V. You must add a driver circuit between the relay coil and the printer port.
|
|
|
|
|
thank you mark, but that was so sophisticated for me to understand cuz i've nothing to do with electronics and i just wanted to trigger a relay using the power from LPT port, can you please suggest another relay that will trigger directly without making any circuit??
thank you mark!
|
|
|
|
|
The LPT port isn't rated to deliver that much current, you will need a driver circuit plus the voltage from the LPT port under higher current isn't 5 volts.
Elaine ![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
|
|
|
|
|
thanx
|
|
|
|
|
Hi,
Does anyone know if there are any adapters available to install a PCI-X 64bit (133MHz) card on a PCIex8 slot which runs at x4 bus speed?? I know that there are interchangeable adapters available to install boards of PCIe (x1,x2,x4,x8,x16). But since a PCI-X 64bit 133MHz runs at the same speed as PCIex4 speed, I wonder if there are any adapters of this kind... 
-Pavan
|
|
|
|
|
You're somewhat confused on terminology at a minimum. The PCIe bus runs at a flat 100hmz, 1x, 2x, etc refer to how wide the bus is, a 1x PCIe card runs at the same speed as a 16x card, it just has higher bandwidth. That said, while a PCIe4x bus might have the same bandwidth as a PCIX133-64 bus (I'm taking your word for it), the signaling details are different, at a minimum 4 PCI-X 64bit words would need converted into 3 PCIe words before being sent onto the PCIe bus. This would require a processor of some sort to do the conversions in near realtime, and would likely still result in some degree of increased bus latency. You'd also have the problem of the card in the adaptor being raised higher than the other cards and not being able to screw into the backplate properly, so I very much doubt any such device would exist.
--
Rules of thumb should not be taken for the whole hand.
|
|
|
|
|
Hi guys,
Has anyone worked with Garmin GPS_18 receiver before?!
I want to use that product to get GPS data in a NMEA format and proccess it on a PIC microchip which supports RS-232 interface and I'm confused between two types of that GPS receiver the one with a cigarette lighter adapter and DB-9 serial interface and the other which has bare wires(LVC). which one shall I use and why?!
Waiting to hear from you all.
Thanks
|
|
|
|
|
Read the specifications[^] and pick the one that fits your requirements. Do you need the PPS signal available on the LVC model? Do you have a 12V (8-30V) supply that the PC model needs?
|
|
|
|
|
Hi,
I'm working with a PCI Express device. I'm planning to let it "DMA" (bus master) write the memory. I'm using a memaccess library from entechtaiwan. This lets me peek and poke memory addresses. When i peek, a pci request read sequence is initiated, when i poke a pci request write sequence is initiated.
Can anyone help me with the following things:
- when i peek a shared memory address, a pci express sequence is initiated. very nice, but what if The Device has "DMA"ed the memory space, and i just want to know the values?
- and the other way around. How to write this shared memory for the PCI bus master to "DMA" read it's values, without the pci express sequence to be initiated?
any ideas, sugestions or laughter would be appriciated... I'd like to understand the matter, before spending a lot of time on it and then discover i can start over again..
Thanks in advance,
Arjan van Heusden.
|
|
|
|
|
DMA is the ability for the device to take control of the system's memory bus (become the 'bus master') and write directly to system memory locations without the need for software running on the system's host processor.
This is really a logical 'bus' concept dating from the time when everything was directly connected to the (single) processor's address and data bus pins. Normally the processor was 'bus master' - it emitted the necessary voltages to drive the address and data buses. For another device to write to or read from the system memory (or any other device connected to the memory buses), a Direct Memory Access [DMA], it had to ask the processor to put its bus drivers into high-impedance mode, so that it was not interfering, electrically, with the buses. When finished, the device then relinquishes its master status.
On a modern system there are many, many different buses which run at different speeds and have different electrical characteristics. To cross between these different buses, there are different bus controllers. On Intel processor-based systems, the key one for PCI Express operations is the Memory Controller Hub, which connects the processors' Front Side Bus to the memory buses (now normally two), the PCI Express channels, and the Inter-Hub Transport which connects to the I/O Controller Hub (on Intel chipsets). On AMD processor-based systems, the memory buses connect directly to the processor, while the PCI Express channels are connected to a PCI Express controller which connects to the processor(s) over a HyperTransport link.
Any operations that involve reading from or writing to a PCI Express device will need a PCI Express read or write sequence, whether driven by the processor or by the device itself. The PCI Express transaction is the read or write operation.
To get the results of a DMA write operation (i.e. the device writes to memory), you simply need to read from the physical memory addresses that the DMA operation wrote to. Conversely, to control a DMA read operation, you need to write the data to be transferred to a particular physical memory location (or locations), and program the device to perform the DMA from those locations. Actually, you can normally program the device to transfer the data from locations that already contain the correct data.
|
|
|
|
|
:|Hi,
can any one give me a win32 api and also a control or library that can get the NEC MAC address from the Hardware itself not from the registry. it will be good if it can be used in C#.
May god give u good health and knowledge.
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
