thanks for the reply.  how would I initialize the flash beforehand within rommon?    I looked through the published rommon command set but didn't see anything relevant other than reset command.

that said, I tried set without success.  it just reports:

Upgrade ROMMON initialized

program load complete, entry point: 0x8000f000, size: 0xcb80

open(): Open Error = -66

boot: cannot open "flash:"

boot: cannot determine first executable file name on device "flash:"

c2811 platform with 524288 Kbytes of main memory

Main memory is configured to 64 bit mode with ECC enabled

this is bizarre because IOS can read it but it seems like its just rommon that can't. 

Try typing flash_init

that command is not supported in my current rommon version.   :-(

I had read one posting where someone had a similar issue so he upgraded rommon but it didn't make a difference.  he eventually indicated his particular issue was tied to the fact that the partitions on the CF card were corrupt.    so not sure if its worth trying to ugprade the rommon ??

not sure how to check the version while within rommon either.  i tried cookie but its a rather cryptic output.

In rommon of you type dir flash: do you get the -66 error?

I do.  

So check this out ... I booted this router (2811) using a TFTP image using tftpdnld -r to avoid rommon from attempting to write to flash after pulling the image over the network.   

Once the IOS image was decompressed and loaded into memory, I did the following successfull command

displaying the flash in detail:

R10#show flash: all

-#- --length-- -----date/time------ path

1     67878324 Dec 27 2013 06:48:16 +00:00 c2800nm-adventerprisek9-mz.151-4.M6-512D.bin

443416576 bytes available (67936256 bytes used)

******** ATA Flash Card Geometry/Format Info ********

ATA CARD GEOMETRY

   Manufacturer Name     

   Model Number           WDC SSD-C51M-4430  

   Serial Number          CB29524751501GC28D03

   Firmware Revision      3.27   

   Number of Heads        16   

   Number of Cylinders    993  

   Sectors per Cylinder   63   

   Sector Size            512  

   Total Sectors          1000944

ATA PARTITION 1 INFO

   Start Sector           233  

   Number of Sectors      1000711

   Size in Bytes          512364032

   File System Type       FAT32

   Number of FAT Sectors  978  

   Sectors Per Cluster    8    

   Number of Clusters     124842

   Number of Data Sectors 998736

   Base FAT Sector        12   

   Base Root Sector       NA

   Base Data Sector       1968 

   Root Cluster           2    

   Backup Boot Sector     0    

   FS Info Sector         1    

ATA MONLIB INFO

   Image Monlib size      123036

   Disk Monlib Size       NA

   Disk Space Available   NA

   Name                   NA

   End Sector             NA

   Start sector           NA

   Updated By             NA

   Version                NA

R10#

Then I formatted the flash using IOS successfully:

R10#format flash:

Format operation may take a while. Continue? [confirm]

Format operation will destroy all data in "flash:".  Continue? [confirm]

Format: All system sectors written. OK...

Format: Total sectors in formatted partition: 1000711

Format: Total bytes in formatted partition: 512364032

Format: Operation completed successfully.

Format of flash: complete

R10#

Then I displayed the device again - noting that IOS can read this flash device successfully:

R10#show flash:

No files on device

511348736 bytes available (4096 bytes used)

R10#

Then I rebooted the router and execution dumps into rommon:

R10#reload

Proceed with reload? [confirm]

*Dec 28 02:07:31.951: %SYS-5-RELOAD: Reload requested by console. Reload Reason: Reload Command.

System Bootstrap, Version 12.4(13r)T11, RELEASE SOFTWARE (fc1)

Technical Support: http://www.cisco.com/techsupport

Copyright (c) 2009 by cisco Systems, Inc.

Initializing memory for ECC

..

c2811 platform with 524288 Kbytes of main memory

Main memory is configured to 64 bit mode with ECC enabled

Upgrade ROMMON initialized

program load complete, entry point: 0x8000f000, size: 0xcb80

open(): Open Error = -66

loadprog: error - on file open

boot: cannot load "flash:c2800nm-adventerprisek9-mz.151-4.M6-512D.bin"

c2811 platform with 524288 Kbytes of main memory

Main memory is configured to 64 bit mode with ECC enabled

Upgrade ROMMON initialized

program load complete, entry point: 0x8000f000, size: 0xcb80

open(): Open Error = -66

boot: cannot open "flash:"

boot: cannot determine first executable file name on device "flash:"

c2811 platform with 524288 Kbytes of main memory

Main memory is configured to 64 bit mode with ECC enabled

Upgrade ROMMON initialized

program load complete, entry point: 0x8000f000, size: 0xcb80

open(): Open Error = -66

boot: cannot open "flash:"

boot: cannot determine first executable file name on device "flash:"

c2811 platform with 524288 Kbytes of main memory

Main memory is configured to 64 bit mode with ECC enabled

Upgrade ROMMON initialized

Entering rommon> prompt after several failed attempts to boot an IOS image. 

Please check your internal/external flash drives for the correct IOS image

and issue 'reset' at the rommon> prompt to re-try the boot process.

Then I display the flash characteristics again (unsuccessfully):

rommon 1 > dir flash:

program load complete, entry point: 0x8000f000, size: 0xcb80

open(): Open Error = -66

dir: cannot open device "flash:"

rommon 2 > dev

Devices in device table:

        id  name

    flash:  compact flash             

bootflash:  boot flash                

usbflash0:  usbflash0                 

usbflash1:  usbflash1                 

    eprom:  eprom                     

rommon 3 >

I am baffled.

Can you create a smaller partition, say 128mb, format as fat16? In Windows of course and not a quick format.

Two years later.  Hopefully it helps someone else.

I had the same problem.  Looks like doing the low-level filesystem "erase flash" worked.Instead of DOS "format flash"

Curious what the

ATA MONLIB INFO

section does.  The DOS filesystem 128MB real Cisco flash card has values there where yours and mine did not for the format flash fake card.  That section is not there for an "erase flash" type "format"

Can you post the results of a dev

hi there ... dev resutls are actually at the tail end of my long post above.  

I should also note that I have tried both fat16 and fat32 as 2800 series CF documenation indicates it supports both.   but resutls are the same.

i can create a smaller partition using fat16 using windows diskpart utility.  i may try 256MB because i pulled a 256MB lexar CF out of this very router and it was fine.  

I have subsequently partitioned the 512MB CF card into a 256MB partition without success.  I went a step further and partitioned down to 128MB without any luck.   I put a 64MB CF card in and it works just fine.   I was really hoping to use these 512MB Cisco CF cards.  

I did end up going into privilged rommon mode and an initfs didn't do much.   A "flash: erase" failed with error code -72.  A "flash: info" reports its full size of 512MB. 

well, thats a good question.  they were purchased off eBay as authentic CF cards.   I have used non-Cisco cards with success in the past however ... i.e. 256MB Lexar card.     But given that IOS can read these cards if I boot from a tftp IOS image, wouldn't that help speak to the integrity of the CF card and its formatting?