Application Note: Network Tools Bus Doctor Media Card Pod Settings

Application Note
Network Tools Bus Doctor™ Media Card Pod
Pod Registers Settings
• Typically, users do not need to configure the Pod Registers tab
• MC pod will monitor the bus and auto-detect the protocol and its settings accordingly
-- MC pod must “see” the sequence of events in order to auto detect correctly.
-- Taking SD as an example.
◊ The pod is set in SD mode when an ACMD41 is received by the analyzer after a CMD0.
◊ The Bus Width is set when an ACMD6 command with a value of 2 is written.
◊ The SET_BLOCK_LEN defaults to 512.
• The MC Pod Registers are restored to their default settings whenever the FPGA is reprogrammed.
• The FPGA is re-programmed when events such as the following occurs.
-- The Bus Doctor CE application is launched
-- An analyzer is selected
-- The capture configuration is changed from State-to-Timing or Timing-to-State
-- The data width is changed in the Pod Registers menu
-- When the block length, block count, or MMC data block size is changed in the Pod Registers menu
• There may also be times when the MC pod will not have the chance to “see” the sequence of events happening
on the bus to auto-detect correctly.
• A good practice will be to save frequently used Pod Registers setting and load them when needed.
Pod Registers Tab
• Bus Width
-- This sets the width of the bus.
-- Can be set to 1, 4, or 8 bits wide
◊ Note the model of interposer board used as MMC and CE-ATA x8 boards are different
• Pod Voltage Reference
-- This sets the value of the voltage provided to the tap board to determine whither the signal being tapped is a high or a low.
-- The Pod Voltage Reference can be set to a value between 0.5V and 3.8V (default 2.5V).
-- Set the reference voltage to the voltage required by your device.
◊ Which should typically be 0.7 of Vcc.
• SDIO Block Size
-- This sets the block size for I/O block operations for Function 0 of the Card Common Control Registers and for function (1-7) of
the Function Basic Information Registers.
◊ If the card does not support I/O block operations (SMB=0), then the registers becomes read-only and shall always read 0x0000.
-- The maximum block size is 2048 (0x0800) and the minimum is 1.
• Block Length and Block Count
-- This sets the block length, block count, and mmc data block size
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Application Note: Network Tools Bus Doctor™ Media Card Pod
Mode
This sets the appropriate bus type
MMC
CE-ATA
ATA on MMC
SPI – MMC
SD
SPI – SD SDIO
SPI – SDIO
Multi-Media Card (default)
Consumer Electronics AT Attachment
AT Attachment on Multi-Media Card
(ATA protocol commands and parameters transported
through the MMC bus interface)
Multi-Media Card using Serial Peripheral Interface (MMC SPI mode)
Secure Digital
Secure Digital using Serial Peripheral Interface (SD SPI Mode)
Secure Digital Input/Output
Secure Digital Input/Output using Serial Peripheral Interface (SDIO SPI Mode)
Pod Registers Settings
• GCS Glitch Removal
-- The help file already explained this setting clearly.
• Response Token According to
-- This sets the version to MMC Version 4.1 or MMC Version 4.2 when detecting the type of response tokens.
◊ Response tokens are decoded differently depending on the version of the MMC specification being used.
• Detect Device Busy 2 to X Clocks After Command End Bit
-- This sets the window of time (in clocks) in which to detect device busy once the command end bit is detected.
-- The window can be set from two clocks (default) to eight clocks.
Detect Device Busy Example
2
3
Application Note: Network Tools Bus Doctor™ Media Card Pod
• In this example, more than two clock cycles have passed before the drive indicates that it is busy.
• Hence, the MC pod started to treat the signal on the DAT lines after two clock cycles which results in unwanted data.
• You can count the number of clocks cycles the device takes before indicating it is busy after the command end bit and configure
the window appropriately.
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WEBSITE: www.jdsu.com/snt
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Product specifications and descriptions in this document subject to change without notice. © 2009 JDS Uniphase Corporation 30162818 500 0909 NTBDMEDIACARDPOD.CS.SAN.TM.AE Sept 2009