45

A720IS Memory Card Benchmarks Example

 

(Guide only, many variables to be considered)

 

 

 

 

 

 

Speed (Kb/s)

 

SD-card model, size

Write

 

Write

Write Read

(RAW)

 

(Mem)

(64k)

(64k)

 

 

 

 

 

 

 

 

 

Canon, 16MB (bundled)

2254

 

1859

1754

3508

 

 

 

 

 

 

A-DATA Speedy, 2GB (FAT16)

2254

 

3164

2532

5572

Kingston, 2GB Ultimate

2254

 

10326

7692

6742

Transcend, SD 4GB, Standard (FAT16 fresh format)

2254

 

3980

3623

5930

Transcend, SD 2GB, 80x

2254

 

7629

5505

6476

Transcend, microSD 2GB, Standard speed, MLC

2254

 

5358

5468

9153

ByteStor, SD 1GB, 50x

2254

 

8060

6132

7021

SanDisk, SD 1GB, Ultra II 60x

2254

 

8840

5591

6606

SanDisk, SD 2GB, Ultra II 60x (fresh format)

2254

 

9600

7123

8445

SanDisk, SDHC 4GB, Ultra II 60x (FAT16 fresh)

2254

 

8718

5627

6715

Sandisk, SD 2GB, Extreme III 133x (fresh format)

2254

 

10686

7594

8316

EMTEC, SD 2GB, 60x (FAT16 fresh)

2254

 

8073

7407

8672

 

 

 

 

 

 

 

• Create card with two partitions

BEWARE: This may DELETE ALL data on the card !

This feature is used with SDHC cards larger than 4GB, on supported cameras (needs multi partition support) it will create a small FAT16 partition with a size of 2MB for CHDK and a larger partition formatted as FAT32 to store the images. On such a prepared card the camera boots up CHDK from the small partition, then the partitions are automatically

swapped, this way the full capacity of the FAT32 partition can be used. The partitions are not shown correctly under MS Windows, only one of the two partitions is shown, to access the other partition without a special system driver, the partitions should be swapped with "Swap partitions"

This option creates a 2 MB FAT partition on the SD card, that's fixed on the code for now. Copy the CHDK firmware extensions to this partition and load them, (The DISKBOOT.BIN and PS.FI2 files). Then select "Make card bootable" in "Main Menu > Miscellaneous stuff", so it does not complain when you write-protect the card.

Next step is to select "Swap partitions" in "Main Menu > Miscellaneous stuff", this will hide this small partition and make the larger FAT32 one visible. We need to format it, and copy CHDK files DISKBOOT.BIN and PS.FI2 to it too, so we can perform "swap partitions" again. So format it in FAT32, copy CHDK, insert it on the camera and load CHDK using "Firmware Update", Select "Swap partitions" and "Make card bootable", write-protect the SD card, (lock with slider on side of SD card) and power- cycle the camera. It should now load CHDK from the small 2 MB partition, but have access to the larger FAT32 partition to store pictures, video and the CHDK folders.