Hi,
The best way to grab frames of a vidio
system from a system architect point
of view is as follows:
A.
Requirements:
1. Independent of types of CPU or machines;
2. Independent
of operating systems;
3. Don't spend CPU resources; (because the board is an
independent system)
4. Don't have to develop an application to deal with
pictures; (because
there are so many, so good image softwares on the market
today).
B. You can do this way to meet all requirements mentioned
above:
1. Board hardware design meets 66MHz/64Bit PCI specs and have a
Master
module and interrupt function in it; This is a technology trend to use
the
fastest PCI bus;
2. Develop software drivers for differenct operation
systems that are
dependent of types of operating
systems;
The following is what a frame drive has to do
under Windows system in
addition to details of your
board:
a. Establish boot function that will initialize
board hardware
parameters during booting period and establish an interrupt
connection
between board's interrupt and the driver;
b.
Establish a hook between a popular image software when it is opened
by users
that usually will have a lot of server functions provided to
outside software
to hook on;
c. Through the software server functions, the
driver can set up
parameters for the board during user's setting period using
the software;
d. When the user of the image software fires
a button to start grabbing
images, it will send a command to driver. When
driver receives the command,
it allocate a shared memory space for incoming
image and transfer the global
address to the board and set board's parameters
to start a PCI transaction;
e. When board receives the
command and has the system address, it can
transfer image it receives to
system memory under Master mode and after one
frame transfer is finished, it
generates an interrupt to the CPU and leaves
job finish information in a
preassigned area to be accessed by the driver;
f. The
driver will receive the interrupt, retrieve the finish
information from the
board and send it to the software through a Window
message that contains
image's system address and all finish information in a
format that the
software can recognize;
g. now the software can display
the image as user wants;
As described above, CPU has nothing to do with
the image grabber. No "MOVE"
instructions are needed.
Weng Tianxiang
Micro Memory Inc.
Chatsworth,
CA 91311, US
Phone: 818-998-0070(o), Fax: 818-998-4459
-----
Original Message -----
From: Marco Brambilla (Wireline) <marco-tpa.brambilla@st.com>
To:
<daniel.deconinck@sympatico.ca>
Cc:
<pci-sig@znyx.com>
Sent:
Thursday, June 29, 2000 2:47 AM
Subject: Re: wintel
> Ciao
Daniel,
>
> > I understand that the CPU ( in a wintel enviroment)
can not 'BURST'
read.
>
> I know it that way, too. This seems to
be due to the way the chipset is
> built.
>
> > If I design
my PCI card as a master can it burst write to the main
memory in a wintel
enviroment ? Will this >occupy any of the CPUs time
other than tying
up the PCI bus ?
>
> You should definitely go this way.
>
Design a master board (think very well about the interaction between the
>
software driver and the master control on your board).
> The board will
need CPU attention only when programming the master state
> machines
(people usually refer to them as the DMA controllers, even if
> this can
generate some confusion).
> Of course you should also implement a way
(interrupt or whatever sw
> protocol you like or MSI) for your board to
request attention from the
> software driver.
>
> Ciao,
Marco.
> --
>
--------------------------------------------------
> Marco
BRAMBILLA
>
> STMicroelectronics
> Via C.
Olivetti, 2
> 20041 Agrate Brianza (MI)
>
ITALY
>
> TPA - Wireline Communications Division
>
tel : +39 039 603.5064 (ST Agrate - TINA
050)
> tel : +33 (0)4 7658.5063 (ST Meylan - TINA
041)
> fax : +39 039 603.5060
> mailto:marco-tpa.brambilla@st.com
>
--------------------------------------------------
>
>
>