FDS Error Codes + Detailed Explanations of Each & Technical Info Quasi-F.A.Q.

[Xious]

FDS Error Code Translations (by Flashback V.E.)
This is a Quasi-F.A.Q; it has no actual questions, but it contains answers to the most baffling question of all regarding the Famicom Disk System. 'What do these blasted error codes actually mean?'
           In it, I provide a detailed explanation of the FDS Error Codes that I feel up to documenting, to the extent that I am willing to document them. I intended this to be my 1,000th post here, however when a thread was deleted, it changed my count and thus, it became post 999, or something like that... Anyhow, enjoy the use of my tidbits of knowledge.
           I worked out the meanings behind these error codes, and the source of the trouble for each by countess hours of working on FDS repair and restoration, and additional unfathomed hours of experimentation and research. While some of this is already known, many of the mysteries of these horribly defined error messages are not discussed in detail anywhere else. If you have any additional information to add, please post a reply in this thread and I will consider adding anything that you have to contribute. Additional credit also goes to Eric, for his excellent documentation of Err.31.
           The goal of this Quasi-F.A.Q. is merely to document the meaning behind each error code. It is not meant to explain how to correct them, nor shall I be documenting any techniques for spindle alignment here or anywhere else in the foreseeable future. Please do not beg for this: I offer complete FDS service and restoration for those unable to complete the task on their own, or for those who wish to have it done by a competent technician who guarantees his work with a first-class warranty.
           As a final comment, please note that although FamicomWorld has my permission in perpetuity to use or publish this anywhere on the FamicomWorld website, nobody else does. I retain full copyright to this document in its entirety and I reserve all my rights as the author of this document.
           If I see it anywhere else, don't be shocked if I come a-knocking. Nobody outside of FW has my permission to publish it in part or in full, in any context whatever. It is Copyright 2012 Flashback Vintage Electronics, if anybody actually cares.  

00-and-10-Codes: These are drive start-up problems.

Err.01: The disk card is not fully seated. Your card-carrier tray may not be entirely engaging, and may be missing sprigs, or require cleaning, etc..
.
Err.02: Power not coming through; battery box not wired, or Power Board board not energized, or drive mech not properly connected to Power Board. Occasionally, this can also be caused by the belt slipping* off the motor pulley as well; or by use of an improper or worn belt or band in its place.
*From what I can tell, the RAM-Adapter sends a signal to the FDS to check if it is properly energized and initialized, and if it does not report back correctly, it generates this error. if the belt has slipped, then the motor does not spin correctly as it has too much tension on the pulley. I suspect that it generates this specific error when this happens before or during the initialization process, and Err.22 if it slips after drive initialization is complete and it begind reading a disk (see Err.22), as either are possible.[/font]

Err.03: Disk is write-protected.

Err.04: (Anti-piracy) File mismatch (manufacturer ID)
Err.05: (Anti-piracy) File mismatch (game title ID)
Err.06: (Anti-piracy) File mismatch (game version ID)*

*I had problems with two 'Hikari Shinwa: Palthena no Kagami' disks. I had overwritten the front side of my primary, original game disk (that had my excellent game save files on the reverse) with that of a bad disk; I was trying to do the reverse (restoringthe bad disk with my good one), and I ended up corrupting Side-A. I figured it was no problem, and wrote both from a third copy, and then all hell opened up, as my original disk was V1.0 (or something like that) and the third disk was a later version (e.g. V1.1).
             The front would load, and when I flipped it over, it became an error-nightmare because of a version mismatch. In the end, I had to wipe my save files and restore the disks from the third copy. Lesson-learned: Do not use half-a-disk for a backup! Always back up both sides (or all four, for multi-disk games)!

Err.07: You have inserted a disk that is either blank, or is the B, C or D side of a multi-disk game. Eject it and flip it over. For multi-disk games, check to see what side you should be using. if the other side of your disk is a single-sided game, such as 'Super Mario bros.', then its reverse (giving the Err.07) is blank.

Err.08: Similar to Err.01. No disk in drive, but insertion switch is engaging; possibly also disk not fully seated. Switch may be damaged.

Err.09: ?? Not disk No.2?
Err.10:  ?? Not disk No.3?
Err.11?:   ?? Not disk No.4?

Err.12-19: I don't think these exist, but it is possible. I may check a dis-assembly of the FDS BIOS for them sometime.

20-Codes: These have to do with properly reading data from disks.

Err.20'Screen data differs'; I am not sure about this error, or its description. I presume it is actually a block error of some kind, based on how it is categorized numerically.

Err.21: Index Spindle<-->Motor and other calibrations off. Drive cannot read initial disk header file.

Err.22: Flow of data is not correct, or is simply not happening*. Data may be garbled, or out of sequence, etc.. This can be caused by:

• Improper Index Spindle & Motor calibration
  
• A bad (or dirty, or not connected) Read Head
  
• The Analogue Board switches not engaging, or not engaging correctly.
  
• A mis-seated Disk Card
  
• A blank A-Side disk, or a blank disk in general.
  
• A dead disk...or a Game Doctor Disk!**
  
• A disk with MIDI sequences on it, or word processor files.
  
• The belt slipping off the motor pulley; or a bad, worn or improper belt or band.
  
• Possibly other things...
  *Essentially, this means that the lights are on, but no-one is home. The FDS senses a disk in the drive, but can' make any sense of the data on it. If there is a problem with the Read-head assembly, then the drive may also think the same thing, as it is trying to read a disk and it can't make any sense of the data because it sees nothing.
  *Game Doctor Disks may give this error if you do not have the correct GD attachment. They will assuredly give an error of this type if you try to read them without a GD device, although other errors are also possible in this situation. This is common for pirate disks out of China.
  
  Err.23: Similar to Err.22 in terms of index spindle-alignment. This is a problem with the index-spindle & motor calibrations and occasionally means you are closer to proper alignment, although this is not always the case.
  
  Err.24: Disk media is damaged. (This is the only way I have ever seen this!)
  
  Err.25: Disk media problems?
  
  Err.26: Disk media is probably damaged. I see this almost entirely when reading from or writing to disks with a dimple or bend in the Mylar. It is also an error when writing to a disk using a 3206 drive, or with a PWR-03 or later) Power Board; essentially, the drive throws an error due to the copy protection. If you have a later drive with the write-protection circuitry, you will likely see this error quite often if you try copying disks.
  
  Err.27: Index Spindle<-->Motor and other calibrations off. Drive cannot read initial disk header file.
  
  Err.28: Similar to Err.22 and Err.28 calibration problems. Usually, this means you are closer to proper alignment, but this is not always the case.
  
  Err.29: Spindle-alignment problems?
  
  30-Codes: These are regarding disk file problems, reading and writing.
  
  Err.30: Disk is full; cannot save.
  
  Err.31: The number of files on the disk does not match the declared (expected*) number of files.
  *This is another anti-piracy measure: There is an index file with game declared number of files that should be on the disk. When reading the data, if the number of files on the disk does not match the declared number of files then the programme throws an error message; possibly with in-game 'Don't Pirate Me.' text..
  
  Err.32-39: I don't think these exist, but it is possible. I may check a dis-assembly of the FDS BIOS for them sometime.  
  
  40-Codes: I think these are software errors and register/addressing conflicts. .
  
  Err.40: I don't recall off-hand, but it may be noted in my book. I think it is 'Disk data still in memory.', or something along that line.
  
  Err.41-49: I don't know if these exist, but it is possible. I may check a dis-assembly of the FDS BIOS for them sometime, although I think I may have seen Err.41 at some point.
  
  
  
  
  
  Note: This was originally from this thread
  
  P.S. I would appreciate if someone could sticky this topic...

[tpm1999]

A very helpful post.  Although many (like myself) are not able to fix many of these issues, this is a great list to point yourself in the direction of getting your unit serviced.

[Xious]

Thanks; I wanted to do something both special and useful... The intent again, is to document on what everything means. I will add more information about some of the obscure codes  when I see them happen again, as I will actually try to replicate them. Err. 09-through Err.11, for example, I have left in a 'questioned' state, and there are error code values that I expect, but I have either not seen, or I don't remember.

I may have notes on them, however some of my notes are in old books, and other notes are not for public consumption, and even if I do eventually disclose them, I would want to reverse the process of rectifying them in order to verify that my noted procedures are totally correct, as to avoid further confusion.

At the least,all information in the above document is (unless otherwise noted) verified and accurate.

Unfortunately,i am far too busy to disassemble the FDS BIOS at this time and go through it. In fact, I think I have a disassembled version,however it is a time-consuming task to examine it in detail. I will likely do this for other reasons later down the road, and may in the process find other error codes. Although they may be so rare that there is absolutely no documentation regarding them, I would add any that I uncover for the purpose of having a complete list; I like completeness. 

[AsteroidBlues]

Delete my post if it isn't welcome, but while I was working on my FDS I was able to run into Error 24 by not having the disk properly seated (the disk is perfect), so it seems it can be something other than it being damaged

[WheeljackDude]

Sometimes, I get an "ERR 22" while I was playing The Legend of Zelda.

If you have that error, all I did was to take out the disk, and put it back in. Lather, rinse, and repeat until it boots up like normal.

EDIT: Turns out that it wasn't a good solution at all.

To counter that error, you have to unscrew 6 screws, turn it over, remove the top cover, carefully move the front piece to the battery tray without breaking the wires, unscrew the black faceplate that was behind the front piece, move the plastic arm under the pressure arm, remove the springs (the third one is behind that little arm. Use the glasses screwdriver to loosen it) with the tweezers, push eject to remove the pressure arm, loosen the screw of the spindle hub with a 1.5mm hex wrench, rotate that thing clockwise until you hear a click, put the spindle hub back in, make sure the screw faces the arm, tighten the screw, and reverse the order (But make sure you have to lift that little arm up before putting the pressure arm back on).

[XC-3730C]

Are these applicable to MGD1 devices?

[famiac]

yes, they share the same error codes afaik

[zxin]

I'm glad someone's finally got a list of what the error codes mean.
And I know this might be nit-picking but I've found some spelling/BBcode mistakes:

Err.02: Power not coming through; battery box not wired, or Power Board board not energized, or drive mech not properly connected to Power Board. Occasionally, this can also be caused by the belt slipping* off the motor pulley as well; or by use of an improper or worn belt or band in its place.
*From what I can tell, the RAM-Adapter sends a signal to the FDS to check if it is properly energized and initialized, and if it does not report back correctly, it generates this error. if the belt has slipped, then the motor does not spin correctly as it has too much tension on the pulley. I suspect that it generates this specific error when this happens before or during the initialization process, and Err.22 if it slips after drive initialization is complete and it begind (It's begun) reading a disk (see Err.22), as either are possible.[/font]

*I had problems with two 'Hikari Shinwa: Palthena no Kagami' disks. I had overwritten the front side of my primary, original game disk (that had my excellent game save files on the reverse) with that of a bad disk; I was trying to do the reverse (restoringthe bad disk with my good one), and I ended up corrupting Side-A. I figured it was no problem, and wrote both from a third copy, and then all hell opened up, as my original disk was V1.0 (or something like that) and the third disk was a later version (e.g. V1.1).
             The front would load, and when I flipped it over, it became an error-nightmare because of a version mismatch. In the end, I had to wipe my save files and restore the disks from the third copy. Lesson-learned: Do not use half-a-disk for a backup! Always back up both sides (or all four, for multi-disk games)!

Err.20(There should be a *colon and a space here.)'Screen data differs'; I am not sure about this error, or its description. I presume it is actually a block error of some kind, based on how it is categorized numerically.

Nit-picking aside, good job.

*This is a colon : : : , not sure if they call them something different where you are. 

[80sFREAK]

Enri claiming ERR 27

２７：ＤＩＳＫ　ＴＲＯＵＢＬＥ　ＥＲＲ．２７　　ＣＲＣエラーを検出

CRC ERROR. It is damage of the surface or either some dirt on it.

Mods, please fix first post, it is confusing newcomers. Thanks.

[UglyJoe]

An alternate listing by Enri:

http://www43.tok2.com/home/cmpslv/Famic/Famdis.htm

error
Drive & disk set related
　01: DISK SET ERR. 01 Disk is not loaded correctly
　02: BATTERY ERR. 02 Disk drive voltage is less than specified value
　03: WRITE PROTECT ERR. 03 I tried to write it while the write protect claw was broken
　04: GAME MAKER ERR. 04 Disk of a different manufacturer was set
　05: GAME NAME ERR. 05 Disk of a different game was set
　06: GAME VERSION ERR. 06 A different version of the disc was loaded
　07: A. B. SIDE ERR 07 Different side disks (front and back) were set
　08: DISK NUMBER ERR. 08 Disks in a different order were set
　09: ERR. 09 A different disc type was set
　10: ERR. 10 A different spare 1 data was set
　
　08 is DISK NO. In the ROM. ERR. Output as 08
　11-19 for disk writer?
　
File access related
　20: DISK TROUBLE ERR. 20 Can not read permission file
　21: DISK TROUBLE ERR. 21 * NINTENDO - HVC * of block code $ 01 not found
　22: DISK TROUBLE ERR. 22 The start mark $ 01 of the block code $ 01 can not be found
　23: DISK TROUBLE ERR. 23 Start mark of $ 02 for block code $ 02 not found
　24: DISK TROUBLE ERR. 24 Start code of $ 03 for block code $ 03 is not found
　25: DISK TROUBLE ERR. 25 Start mark of $ 04 for block code $ 04 $ 04 not found
　26: DISK TROUBLE ERR. 26 I can not write correctly on a disc
　27: DISK TROUBLE ERR. 27 Detect CRC error
　28: DISK TROUBLE ERR. 28 The timing is not matched by loading the disc (the head went to the end while reading)
　29: DISK TROUBLE ERR. 29 Timing is incompatible with writing to the disc (the head went to the end during writing)
　
User save related
　30: DISK TROUBLE ERR. 30 Can not write to disk (insufficient capacity or forced termination due to drive protection)
　31: DISK TROUBLE ERR. 31 The number of data on the disc does not match, or the number of mount files to be written has become negative
　
　35: DISK TROUBLE ERR. 35 Failed to write test file (block code $ 05 file)
　
Other
　40: DISK TROUBLE ERR. 40 There were files that could not be loaded at batch load (the number of files is insufficient)
　41: DISK TROUBLE ERR. 41 Unknown (There is a notation of ERR.41 in the description of Kikuko II)
　
　　　* DISK TROUBLE ERR. After 35, error judgment is done by software routine rather than ROM routine

[portnoyd]

Probably the best place to ask this question, of the error codes related to disks (mostly in the 20s, like Err. 24), are they fixable by rewriting the data through a FDSstick adapter? If you can't, the disk is basically junk, right?

[P]

It seems to me that errors 20 to 27 are very common and especially unreliable errors for trouble shooting. They generally means that either the disk or the disk drive is bad in some way. If it is the disk:
If it's dirty, hopefully carefully cleaning the disk is enough.
If the disk has lost its magnetic orientation, it must be rewritten (which leads to all the problems with home-rewritten games).
If the disk is physically damaged, it is junk.
If it is the drive, it is usually the head not being in the correct place, or it needs cleaning or something.
It can also mean the power supply is bad. Insufficient voltage should trigger error 2 but I've seen bad batteries triggering DISK TROUBLE errors as well.

Errors 01 to 10 are probably very reliable and normally only happens when they should.

[portnoyd]

Woof. You basically answered the question of "Why do people say the FDS is more trouble than its worth".

[P]

Some people say that. But these are only problems that popped up on the forums over the years. By very common I mean it's the most common among errors, not that most disks has these errors. Personally I never had any problems with any of my disks. I got a few broken ones, but in those cases the previous owner had told me he couldn't get them to work so it was expected.

Now of course FDS disks and drives are old, these errors will become more common as time pass. Really, drive-replacement solutions like the FDSStick is the way to go. Much better than any flashcart solution. In the future maybe the RAM adapter can more accurately be reproduced as well (it's already being done in FPGA in the Everdrive, the Powerpak and the MiSTeR, although at an approximated level).

[ericj]

If the disks are Game Doctor disks, you usually get errors 20, 21 and/or 22 (iirc) when attempting to load them without a game doctor device.