12 Mar
2005
12 Mar
'05
9:01 a.m.
Dwight K. Elvey wrote:
Hi
I've always been looking at using a DSP chip for this job.
I did expect to read parts of a track at a time and then
reassemble them as condensed data. Chips like the Analog
Devices 2181 have some 80Kbytes of onboard RAM. Although,
it can't all be used for storage at the same time and
some is needed for program space. These chips can be
implemented with a real minimum of outside circuits.
they even have a serial SPI that can be used to read
disk data at higher speeds. These processor run at 30 MIPs
plus. They can run some operations, such as data moving
to arrays in single cycles, including updating of pointers.
They can do as many as 5 operations in a single cycle.
The can bootstrap from simple slowspeed EPROM of FLASH.
One could easily connect one of these to that USB chip
that someone pointer to earlier.
Dwight
Look what you are doing is building a generic floppy disk controler.
The only high speed device what you use to sync the data/clock pulses
to the system cpu clock. The rest is software. I'd sooner use a CPLD
designed for generic bit sampling but a PIC would also work with
a digital data/clock seperator. Now would getting the people who do
cat-weasel create a USB version be a better goal?
Ben alias woodelf
PS. What about hard-sectored floppy disks, that too may need reading
too?