Topic: CMD FD-2000 Manufacture Dates

[TacKer]

The recent discussion about FD drives prompts me to share the following.  Awhile back, I had all four of my CMD FD-2000 3.5 inch Disk Drives apart for cleaning.  It was at this time that I noticed that the newer ones had 4 digit production dates on the PCB (Printed Circuit Board).  For example, one had 9649 within a white rectangle.  See attached picture.  It appears this is the last two digits of the year followed by the week of production.  Hence, 9649 means the 49th week of 1996.

Besides the PCB, the Power Supply is also stamped with a four digit number.  In this case, the format appears to be month followed by year.  For example, 0197 was made in January of 1997.  See attached picture.

Below is a listing of all four of my FD-2000's showing the purchase date, dollar amount, PCB and Power Supply dates.  All four were purchased directly from CMD and shipped to the same address in the United States.  The date and dollar amount is taken from the original invoices.

1.  Purchased 1995-12-26 for US$159.00,  PCB undated,       Power Supply dated 1294.
2.  Purchased 1998-02-20 for US$179.00,  PCB dated 9649,  Power Supply dated 0197.
3.  Purchased 1998-12-28 for US$159.00,  PCB dated 9850,  Power Supply dated 0998.
4.  Purchased 2000-01-05 for US$179.95,  PCB dated 9948,  Power Supply dated 0699.

Any comments, corrections, or criticism welcomed on the above speculation.

Thomas

[RCtech]

Here are my boards, left side the modified FD-2000, right the FD-4000. They don't have the white rectangled field with a serial number, there are no information of the cases and I also don't know when the pre-owner bought them Are these FD's without identitiy?

Actually I know the boards of RobertB's and Kiipu's FD-2000, both have a silver metal oscillator. My drives and Robert's FD-4000 have a black plastic oscillator. Are the other FD-2000 boards have a silver oscillator? In my modifed FD-2000 the small socket for the FD-2000 floppy controller was soldered manually, also the ROM socket. So, was it an FD-4000 board, reworked to an FD-2000? Sounds not useful, except it was made by CMD to sell more cheaper FD-2000, or they ran out of ED drives. But if it is possible to downgrade an FD-4000 board to an FD-2000 board, then it should be possible to upgrade an FD-2000 board.

[TacKer]

RCtech
None of my four FD-2000's have visible outside serial numbers.  They do have two white decals on the bottom of the metal case though.  The first decal is marked FD-2000 while the second one is marked REVISION 1E.  See attached picture.  These decals sometimes fall off over time and of my four drives one is taped on and another is missing the decals.  The only visible serial number on the inside is the serial for the TEAC 3.5 inch disk drive.  All four of my FD-2000's use TEAC FD-235HF drives.

Attached is a picture of my undated FD-2000 PCB board.   I am unable to locate a silver colored oscillator.  Is this the silver colored part that is marked FOX on my drive dated 9649 as pictured in my first message?

Something to consider is that CMD discontinued the FD-4000 before the FD-2000.  Take a look at some of the CMD catalogs over at http://www.bombjack.org/commodore/advertisements/ .  Possibly CMD still had some FD-4000 PCB's on hand and used them to fill FD-2000 orders?

Thomas

[RCtech]

Yes, it seems very obvious know that CMD discontinued the FD-4000 earlier. That would explain FD-2000 boards with a black oscillator, and this one you have has also no white area on the board like my real FD-4000. You could see the same things also on RobertB's FD boards. Maybe they ran out of Teac ED drives and tested no alternatives. In my FD-2000 was also a Teac HF-235, but that's a standard PC HD floppy. You should be able to use any other PC floppy, even slimline ones. Important is only, that they could be jumpered to DS0 (Drive Select 0). But I don't know what happens if you connect an 1,2 MByte 5,25 PC floppy to an FD, would be interesting. On an 1581 you can easily connect an Amiga-compatible 5,25" drive mechanics, that works.

I made a montage of your boards and marked the oscillators. It seems that FD-2000 models had a silver oscillator, the FD-4000's a black oscillator. So at least these should work when an 68pin-PLCC socket for the floppy controller is added. But I don't see a reason why it shouldn't work with the other boards, both oscillators have 24.0000 MHz. You also can see that there's enough space to use both oscillator types, perhaps there are soldering holes for two oscillator sizes. The different frequencies 2 MHz / 4 MHz will be generated by different settings of a frequency divider, maybe by using the new jumper configuration. Or the new floppy controller creates a 4 MHz signal. Whatever, I didn't even need to replace the 2 MHz CPU, the modded worked with it, too. Then the CPU runs overclocked now, at double speed! Try this on a PC processor!

It's also very good to see on your boards: The main chips are all made by CMDµ, the FD-2000 has a 2 MHz CPU, the FD-4000 a 4 MHz CPU. But the VIA's have 2 MHz in both drives, so disk access and data transfer would not be faster on both drives, like I noticed as I formatted an ED disk as one 3,2 MB native partition, it took on both drives 1:30 min. The only way to compare the speed is that someone writes a small program for the floppy. It must be started from the computer, executed in the floppy's memory and then delivering a result back to the computer.

I also wanted to remember: The VIA 65xx22P and the CPU 65xx02P are not the Commodore MOS/CSG 6502 or 6522 like in the 1541, they are clones made by CMDµ or Rockwell. The VIA 65xx22P has not the shift register bug and the 65xx02 CPUs are partially incompatible to normal 6502's because they have no illegal opcodes. More infos:

65C02
    •    CMOS technology
    •    additional commands and addressing modes
    •    no illegal opcodes
    •    some commands need under certain cirumstandes mode cycles as the standard 6502
    •    used in the extended Apple IIe, Apple IIc and early accelerators for 6502-systems
    •    manufactured by Western Design Center
65SC02
    •    partially reduced command set (no bit commands, genuine subset of the 65816) in comparison to the 65C02
    •    used in the Atari Lynx and Watara Supervision with 4 MHz
    •    manufactured by GTE and CMDµ


Long talking, but there's only one way to find out if the rework works on an original FD-2000 board: Try it! 

[TacKer]

RCtech
Thank you for the clarification of the location of the oscillator on the PCB.  Attached are pictures of the remaining two PCB's I own.  (I increased the resolution on these pictures so that you could zoom in better.  Updated the undated PCB picture as well.  Will update the first picture shortly.)  One has a silver colored oscillator and the other has a black colored oscillator.  The other chips seam to differ as well between the two.  [Edit:  I mean that the maker marks of the chips differ between the two, not that the chips have different functions.]  I guess they used what ever chips were available in the supply channel.  I wonder if CMD made there own PCB's or contracted them out.

Hope this information helps your in research.
Thomas

[RCtech]

I don't think the boards are different. It would also make no sense two create a board with two sockets for different floppy controllers and then use different components. Even the CPU is socketed, you'll find this in no 15xx drive and also not in the CMD HD. It's socketed to use a 2 MHz or 4 MHz CPU in the same board, depending on the model. If CMD used 4 MHz CPUs in both FD versions, there wouldn't be a socket neccessary.

Something else: The ROM's of the FD-2000 and FD-4000 must be very different, because they are using completely different controllers. But if you read in the appendix of the FD-2000's manual, they showed how to install the optional Real Time Clock on the board, into the ROM socket. So both drives, FD-2000 and FD-4000, are supporting the same RTC model, although the DOS is different programmed. Another factor what leads to the result that the boards are identical. The FD-4000 had the RTC always installed, but the upgrade information is still in the manual.

The chips are also not different. The RAM chip is another manufacturer, so it has another number. But if you'll search for the datasheets, it will be the same memory size and orientation. It's a static 32k x 8 RAM chip, here's the datasheet from Hynix. The TTL logic chips are also from different manufacturers, so they look different. They may also have different types of the chip (LS, HC, HCT etc.), but important is only 74 and the following number. I'm sure they will be all the same. But I'm too lazy to compare them all

[TacKer]

RCtech
My mistake in wording the above.  I meant the chips have different maker marks.

I agree that CMD used a standardized PCB for both the FD-2000 and FD-4000.  This cuts down on manufacturing costs.

Sorry for the confusion.
Thomas

[maraud]

I cracked my FD2000 open.  It looks exactly like the one pictured earlier in this thread IMG_9850.JPG.  It's a REV1E with 2086 in the "white box" area. Unfortunately it doesn't have the emply floppy controller socket pre-installed.  I do have an ED disk and blank floppies.  Will have to try this conversion but I'll need to get the FD4000 bin file.

[TacKer]

The DOS ROM on all four of my drives was V1.40 according to the sticker affixed to the top of the ROM.  See the pictures previously posted above.  For the location of the DOS ROM on the PCB, see the attached scan taken from the 4th edition of the User's Manual.

The DOS ROM version installed on a FD-2000 may be another way of dating how old the drive is.  Does anyone know how many versions of the DOS ROM exist for the FD-2000?

[RCtech]

I only know V1.34 and V1.40 for FD-2000 and FD-4000 seperately. The CMD HD BootROM has more versions, I know 2.52, 2.78 and 2.80.

[TacKer]

I found a Commodore 128 software program that will display the DOS ROM version installed in the FD-2000 disk drive.  This program will come in handy for those who do not want to take apart their drive to look at the DOS sticker or for those missing the DOS sticker.  The program is called C128 System Information v7.5 and it can be downloaded at the website below.  I tried it and it worked just fine with my FD-2000 disk drive.

http://www.mirkosoft.sk/downloads.html