μ
PD720231
5. Boot Mode
R19UH0094EJ0100 Rev 1.00
Page 21 of 30
Mar 1, 2013
5.
Boot Mode
There are 2 boot modes in the
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PD720231, SROM boot mode and HDD/SSD boot mode.
HDD/SDD boot mode has Quick/Slow enumeration option. These are selected from GPIO setting
during initialization.
Table 5-1. Boot Mode selection
GPIO0 GPIO1 GPIO2 GPIO3 Mode
Option
x x x 1 SROM
boot
−
1 0 0 0
Slow
enumeration
1 0 1 0
HDD/SSD boot
Quick enumeration
5.1
SROM boot mode
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PD720231 boots up with internal firmware, and uses parameters and firmware patches from external
SROM (SPI Flash). Utility tool is used to set these parameters and firmware patches into external SROM.
Please refer to the application note of utility tool in more detail.
5.2
HDD/SSD boot mode
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PD720231 boots up with internal firmware, and uses parameters and firmware patches from HDD/SSD
devices. Utility tool is used to set these parameters and patches into HDD/SSD. Please refer to the
application note of utility tool in more detail.
Quick/Slow enumeration are selected with pin strapping option, as in Table 5-2.
Table 5-2. Quick and Slow enumeration setting
Setting Behavior
Quick enumeration
Some HDD drives take time for spin up, and if PC may not wait this period,
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PD720231 may not be enumerated properly. To prevent this case,
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PD720231 responds default information of internal mask FW to host system.
After getting information of SATA device, it disconnects, connects again, and
responds the latest information of SATA device to host system.
Slow enumeration
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PD720231 starts the connection to host system, afer Initialization of SATA
device completes. In this mode,
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PD720231 keeps its connection to host until it
actually plug out. This mode is recommended, in submitting to USB compliance
test.
