IDE VS SATA

[TKS]

Hi all,

i was wondering how difficult it should be to make instead of use of a ide harddisk use of a sata disk...

i have found a pdf file (downloaded form the SATA group site..)

but i as newbie don't know much if it is usefull they talk about registers etc...

could anyone take a look @ it and give his opinion..

**broken link removed**

i think a sata disk should be more easyer and faster for us to use for example a mp3 player...

TKS

 

[samcheetah]

i think the topic should be PATA vs SATA. PATA (Parallel ATA) is the interface which has been in use for a long time. parallel data transfer has quite a few bottelnecks; noise being one of them. to reduce the noise the number of conductors in the ribbon cable is increased. PATA drives use a 40 pin - 80 conductor cable to reduce noise. in addition to that, the maximum attainable data rate using PATA is low as compared to that attainable with SATA.

nowadays most of the technologies used for data transfer are serial technologies, SATA being one of them. SATA reduces the number of conductors required for communicating with other devices in the computer and it increases the data rate. SATA has a lot of potential. if it hadnt been for the introduction of the ATA133 interface by Maxtor SATA would have came into the market a long time ago.

so summarizing all of it i would say SATA is the way to go!!!!!!!!!

i hope that helps

 

[Exo]

Yes, but if you want to interface SATA yourself (with a pic) then it would be pretty much impossible. A serial link obviously increases the clock speed (by a LOT!) and a pic can't handle the speed required to do so (by far)

 

[TKS]

wy the

bottleneck wil be the mhz..???

would is also be so if you use the 40Mhz pics..???

and wy you cant use the sata @ a slower speed..??

i guess the pic ide interface isn't as fast as the 133MBit/sec


wich chip would be a option then..???

TKS

 

[bmcculla]

The 133 is mega BYTES per second. The internal busses of the PIC arn't even running that fast.

SATA claims 150MBytes per second. which would require a 1.2GHz clock to run that much data through a single serial channel. Thats about 120 times faster than the PIC is executing instructions.

The SATA is probably running a couple differential serial channels to get that bandwidth but it would be impossible to use a PIC to bit bang this bus.

Brent

 

[pike]

SATA was designed to reach higher speeds such as 380 MB. The only real draw back limiting this speed is the hardrive speed. 15000 RPM is the fastest on the market.

So until they can find ways to increase data output from hardrives, i would stick to PATA.

 

[bsodmike]

That may be true, but I for one download alot of Anime off the net. Each episode comes to abou 175MB and some of my series are 70eps or so long. I can move data amazingly faster between drives and if I were on PATA (I used to be!) it would take sooo much longer, as I tend to 'process' anime in batches of 5gig at a time.

processing: renaming them perfectly and organizing

I maintain a mirror of all my new anime on two SATA hdds on my shuttle here and on 2 hdds (PATA) on my linux server, so at any given time I'll have a full backup..yes these are very precious. Off to DVDR they go when they are complete

 

[TKS]

Ok

but wi would a IDE work and SATA not..???

because in the mp3 project i have read that it works also whit a pic..

(IDE ) sow to free up some pins i thought SATA should also be posible

sata uses only 7 lines 3 grounds and 2 channels (serial) Tx+/tx- and Rx+/rx-....

i'm sure the ide of the projects are also not working on 133MB/sec..

i don't know how you figured out the needed frequency for sata...

but i think that's not the true number..

on my motherboard there is a litlle chip that is the sata chip and that one doesn't work @ that freq..

only the main cpu does..

but i can't imagine that that one is spending 1,2Ghz when transferring data..

and then we aren't talking about haveing a Pentium 200Mhz and putting a pci sata card in it..i'm sure it wil work..

offcourse not using its total potenial but it wil work..

TKS

 

[Exo]

That may be true, but I for one download alot of Anime off the net. Each episode comes to abou 175MB and some of my series are 70eps or so long. I can move data amazingly faster between drives and if I were on PATA (I used to be!) it would take sooo much longer, as I tend to 'process' anime in batches of 5gig at a time.

processing: renaming them perfectly and organizing

I maintain a mirror of all my new anime on two SATA hdds on my shuttle here and on 2 hdds (PATA) on my linux server, so at any given time I'll have a full backup..yes these are very precious. Off to DVDR they go when they are complete

Give both PATA discs their own channel (both on another IDE controller, not master-slave on 1 controller) and it will go equally fast. Like said, the current bottleneck is the drive speed, not the bus

 

[Exo]

Re: Ok

but wi would a IDE work and SATA not..???

Because SATA is serial, a byte is clocked out at the SATA bus speed and the receiver has to follow, a pic woudn't even see a blip, its way to slow...
The receiver controls signal flow (can stop between bytes if it can't follow) but once the transmission of a byte has begun the receiver must keep up with it...

PATA puts all the bits on a separate line for you to read, and if you're ready to continue you just give a clock...

but i can't imagine that that one is spending 1,2Ghz when transferring data..

The SATA controller on your pc's motherboard is a deticated chip, its only purpose in life is to run SATA, it's designed to do this so it can handle the speed...

 

[bsodmike]

Give both PATA discs their own channel (both on another IDE controller, not master-slave on 1 controller) and it will go equally fast. Like said, the current bottleneck is the drive speed, not the bus

Yup, all my PATA systems that have more than 1 hdd have each hdd on a different chan (as master per chan)...still notice a boost in SATA speeds. All drives here are 7200RPM with 8MB cache as well....

 

[TKS]

soow exo

you are saying that the chip on a mobo whit SATA has app. 1,2Ghz

it even has a heatsink..!!!



and how do you know that the protocol isn't build in that way that for evey bit send or recieve due the other channel a command is given to go to the next bit..????

soow that the sata disk waits whit going to the next bit as soon as it recieves the signal..

In normal live i'm a computer seller and system administrator.

i'm sure that a IDE disk @ 133 (WD still @ 100) can't beat a SATA disk..

also not when 1 disk per channel.. is connected..

i don't have the resources but i think it is very good possible whit a PIC18 series.. because i think there is a busy or wait funcion..or a acknowledge..??

maybe you have to confirm evey recv bit..?? then it would be possible right..??

SATA can't be cpu eating....

well we will see..

TKS

 

[bsodmike]

TKS - I'm amused by the way you 'write'..... takes a bit of time to read and comprehend your posts but heh I understand The reason why (I think) that a PIC can not interface with an SATA hdd would be cause data moves in a serial fashion. If you look @ Nigels tute on RS232 coms (I know that is async, is SATA async as well?) note how the delay between bits gets smaller and smaller which would mean the clock speed of the PIC has to get bigger. Weight the two and you can see that a 40Mhz PIC will not be able to handle the incy wincy delays....

...this is how I understand this, please please correct me if I am wrong!

 

[TKS]

uhhmm

i untherstand your point..

but i think it cant work in that way....

well in that way it could only work if the speeds of both devices is verry the same..and that you miis never a bit or read the same one twice..

mhh...

wy should the protocol be in a way that the HDD keeps the bit pos on..
as long as de driver chip (our pic) doesn't give him a hint now go on to the next..

??

if we bove take a look @ the zip..above in the binning of the post..i'm sure we will have a answer on you sync question..

TKS

 

[Exo]

There is a clock signal for synchronization offcourse, but you can't run it so slow for a pic to follow...

A 40Mhz pic will run 10 000 000 instructions per second, you need about 5 instructions to get the bit of a pin, and then you need to store it, so you can create a byte to send to the MP3 chip, in the very best case a couple of 10 instructions... Let's say about 20 instructions per loop, so our 10 000 000 is down to 500 000 ... BITS... 8 bits in a byte => 62500 bytes. So a 40 Mhz pic can get about 65K / second... (in a very optimistic case of only 20 instructions / Loop)

That would means the clock would have to run at 500Khz max, or the pic can't follow.

SATA simply can't run this slow! The clock speeds are WAY beyond that, even the minimums ... Take a look at the zip you posted yourself. There talking about ps in there, PICOseconds... :roll:

 

[phalanx]

You could use a SerialATA interface chip to handle all of the high speed timings and then read the data off with a microcontroller at a nice controlled speed.

You could also look into the Ubicom SX processors which are designed to be programmed and behave like a PIC only they can work around 100MIPS!

 

[TKS]

ok...

can you also tel me what the minimum freq needed is by reading

the datasheets..??/


i cant figure it out..

TKS

 

[TKS]

did you also read this..??

69-87 HIGH SPEED SERIALIZED AT ATTACHMENT Page: 34
1=Ultra DMA mode 0 is supported

isn't then the maximum speed 33MB/Sec...

Soow.. 33.000 Kbyte/sec

IDE:

but how does this process work in IDE>.??

or is it over there working like i sais whit the pin..?? waiting until read or write is succes..??

soow that there actualle isn't a minimum speed..???

TKS

 

[TKS]

yeah funny 2

well tell me which chip i need...

to communicate whit SATA or IDE....