µPD720130
2.2 External Pin Setting
Usually, serial ROM should be used to keep Vendor ID, Product ID and some additional USB related
information. And then, the external pin setting of the µPD720130 is not so important to realize USB to IDE bridge
system. The recommended external pin setting is as follows.
Table 2-2. Recommended External Pin Setting
Pin Name
Setting
MD1
1
MD0
SCL
0
Pull Up Note 1
SDA
Pull Up
DV1
“L” clamp
DV0
“L” clamp
CLC
“L” clamp
PWR
DCC
“L” clamp
Pull Down Note 2
GPIO(7:0)
“L” clamp
PIO(14:15)
“L” clamp
PIO5
“L” clamp
SPD
“H” clamp
TEST(3:0)
“L” clamp
SMC
“L” clamp
IRQ0
“L” clamp
Notes 1.
2.
If serial ROM size is more than 2 Kbytes, SCL should be pull down.
If target IDE device is not fixed, it is preferable that DCC pin can
switch pull-up or pull-down.
The setting for any other pins such as CMB_BSY, CMB_STATE depends on USB2.0 to IDE Bridge system.
For example, if two IDE controllers control one target IDE device and one of two IDE controllers is the µPD720130,
CMB_BSY and CMB_STATE are used to handshake between two IDE controller chips. On the other hand, when
the µPD720130 is only controller of target IDE device, CMB_BSY should be opened and CMB_STATE should be
clamped to “L”.
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Data Sheet S16302EJ3V0DS