CF Adapter for IDE/8255 interface.

[rpalmer]

Hello everyone,

It seems I have managed to get 3 of my Compact Flash cards to work on the IDE2CF adapter (see attached picture). The interface shown in the YouTube videos has the CF card fixed as a master, I have changed the Eagle files so that the Master/Slave select is available.

The two highest capacity cards (512MB and 2GB) appear to not work (they hung the computer for some reason)  .

The testing I performed was to simply ready the IDE device geometry, so I can not see why the fore mentioned cards failed.

I also tried to read a single sector of data from those cards that worked and again the computer hung.  My guess here is that the driver for the IDE interface needs some added code to handle the CF cards as the adapter is supposed to work in True IDE mode (see attached PDF file).

The urls for the videos of them being tested are:


CF-16Mb.AVI

CF-2GB.AVI

regards
rpalmer

[Bryce]

Hi rpalmer,
     two things that might be causing the problems: Did you format the CF cards yourself? If they have FAT12 or whatever on them, they are not going to react like the hard-drive. Also, CF cards write in a particular page-size, so you have to fill the page, wait for the data to be written to flash, then write the next page. This is quite a bit more strict than working with standard IDE. There's lots of info about this on the interweb, but I can also send you some documents if you can't find anything useful.

Bryce.

[rpalmer]

hi bryce,

The first thing I am trying to do is simply read the device geometry and then read the first sector of data from the card.

I have downloaded some CF manuals in PDF form (one of which is from Sandisk).

As for the writing to a CF card, I suspect that the internals of the CF manage the written data. However, I will check for examples of code which write to CF cards and see if they need to send more data than what is normally sent for writing a standard IDE sector.

As for the cards that failed to even read the geometry, i again suspect that some cards will fail as they may be too quick for the CPC to handle.  I do recall from the past that some people on a forum stated that some cards may not work since they have different interface handlers and expect the host to be quick enough to handle the expected data transfer rate even in PIO Mode 0.

rpalmer

[Bryce]

I'm not sure if you know the MyIDE device for the Atari XL/XE. It's routines work perfectly with IDE harddrives and CF Cards. It might be worth taking a look at what he did. If an XL/XE is fast enough for CF Cards, then out beloved CPC should easily manage it.

Mr Ataris (the designer) Site can be found here: http://www.mr-atari.com/

Bryce.

[rpalmer]

bryce,

I went to the website and found i need to register, but nothing i entered into the register form would work, so think this site is useless.

rpalmer

[Bryce]

Hmmm, don't know where you landed that you needed to register, but here are direct links to:

His hardware: http://www.mr-atari.com/myide.htm

The Forum: http://www.atarimax.com/flashcart/forum/viewforum.php

Software and further notes: http://www.mr-atari.com/hardware-info-old.htm

Bryce.

[rpalmer]

Hi bryce,

I worked out why my registration failed.

rpalmer

[Bryce]

And? Why?

Eitherway, more importantly, did you find any useful information there?

Bryce-

[rpalmer]

hi bryce,

In short there is only the binary images to use on the machine (sadly no information about how they use CF cards).  There is documentation which is downloaded, but nothing that i already new.

The interface is in fact only 8 bit IDE, so the attached Hard drives are only used with 50% capacity.

rpalmer

[Bryce]

Yeah, I knew about the 8-Bit solution he uses, but I thought there might be something in there about the CF cards.

Bryce.

[redbox]

"Looks like it don't work", classic line 


Very interesting to see your progress though!

[rpalmer]

I have good news and not so good news.

The good news is that for some reason my drivers do work but have debug stuff in them, so screen output is corrupted and the driver as is would not be a useable as they are now.

The bad news is if i remove the debug code or disable it the drivers fail to read sector data (again I have no way of knowing why?).  The debug code saves all registers and the outputs the saved registers as text before restoring them and exiting back.

My good version which was in mode 1 seemed to not work in mode 2 with debug code, so again why fail?

I first thought that it might be timing, but i replaced the debug's with waits for 1 second and again it fails so again why?

I will continue to look more deeply.

rpalmer

[rpalmer]

Hello all,

Well I have managed to get the IDE/8255 interface to read CF cards (not tested write yet) with my IDE2CF adapter.
It took some time to work out why my previous attempts failed, but thats now in the past.

I will shortly have a youtube clip up showing it in action.

rpalmer

[rpalmer]

just to clarify, the adapter works on my 32 Mb CF card which is made by Kodak.

I am still workin on my other cards (128M/512M/1G) which are sourced from Disk Smith Electronics (the maker of which I have not looked into).

rpalmer

[rpalmer]

Further testing today showed that my 128 Mb CF card also worked (only with reading)

However, I have come to the conclusion that my 512 Mb and 2 Gb  cards will not work on the adapter even though they work on a PC.
It seems they refuse to even allow the adapter to read the device geometry when first using them.

So for now the adapter does as expected and I am in the process of making a number of adapters to work with the IDE/8255 interface cards.

I will soon update the price list spreadsheet with the adapter costs included.

rpalmer

[Gryzor]

This sounds all very promising...

[Bryce]

Hi rpalmer,
      I've been musing over the problem that the small cards work, but the large one's don't. And as far as format and protocol is concerned they are all the same. The only thing that leaves is voltage and current. Are you sure that the voltage being supplied is enough for these cards and if so are they also getting enough current? This is the only explanation I can come up with for the issues you've described.

Bryce. 

[rpalmer]

i will check the voltage, but the voltage for the cards is sourced from the CPC bus which is 5V.
The adapter card has a 100 uF capacitor between Vcc and GND.

The older cards no doubt would have been working from a 5V perspective.

I suspect the current is not a problem as I only have my ROM board and interface attached.

rpalmer

[rpalmer]

hi bryce,

I did check the voltage with the 512Mb CF card attached and it is 4.98V and so is well with tolerances.
As for current supplied, the older CF cards would no doubt use higher currents than newer CF cards, so its unlikely that the current supply is an issue.

I also bought a brand new 4Gig SanDisk CF card last week and it appeared to allow me to read the CF geometry, so it is highly likely that some of the cards will not work no matter how i configure the CF adapter software/hardware.

rpalmer

[xesrjb]

and what about using a SD-IDE Interface? And what about normal hard disks? Any results Who tested it?

xesrjb

[rpalmer]

to connect a euro-styled interface to a classic interface, the attached pictures show the adapter (not soldered) which allow for a cable to be built and then attached.

rpalmer

[xesrjb]

I think it's usefull to have a guide/instruction how to use and install HDOS Step by Step in combination with the CF Adapter.

xesrjb

[TFM]

to connect a euro-styled interface to a classic interface, the attached pictures show the adapter (not soldered) which allow for a cable to be built and then attached.

rpalmer

Well, if you take a look at the picture, then you see that it will create a shortcut. The spacing of the pins and of the pcb doesn't fit. So you must use a cable to connect.

[rpalmer]

hello TFM/FS,

Yes I am aware of that very issue. I am looking at making one which is correct.

I should note that the pads are spaced 0.1 inches apart, but making a double sided version is always going to have them not aligned on each side.  I am thinking of shrinking the track widths so that is less of an issue.

I was only showing what sort of adapter is required to overcome the connector issue.

rpalmer

[TFM]

Good luck!