
3. Clocking and Reset Options
48
Tsi310 User Manual
80B6020_MA001_05
Figure 3: Programmable Pull-up Circuit
Since the internal PLL is bypassed in PCI mode and the S_CLK input is used directly, the
Tsi310 has no need to distinguish between the PCI 66 and PCI 33 modes. Therefore the Tsi310
does not have an I/O pin for the M66EN signal on its secondary interface. This signal should be
routed to all devices on the bus in case the other clients require it.
3.4
Clock Stability
The PCI/PCI-X architectures specify that the bus clock must be stable and running at its
designated frequency for at least 100
s prior to the de-assertion of the bus reset signal. As the
Tsi310 does not generate the secondary bus clock but does control the secondary bus reset
signal, it must detect when the S_CLK input has become stable in order to meet this
requirement. The input signal S_CLK_STABLE is provided for this purpose. During a bus reset,
the bridge waits for the assertion of the S_CLK_STABLE input before executing the mode and
frequency determination sequence described in
3.3V
3.3V
S_PCIXCAP
S_PCIXCAP_PU
Weak
Pull-up
Strong
Pull-up
For PCI-X
66 MHz Cards
For PCI-X
100/133 MHz Cards
For PCI
Cards
S_SEL100
3.3V
For 100 MHz
For 133 MHz
Enabled During
Bus Capability
Determination
Tsi310
10k
0.01uF
0.01uF
0.01uF
56k
10k
1k
Summary of Contents for Tsi310TM
Page 8: ...Contents 8 Tsi310 User Manual 80B6020_MA001_05...
Page 10: ...List of Figures 10 Tsi310 User Manual 80B6020_MA001_05...
Page 12: ...List of Tables 12 Tsi310 User Manual 80B6020_MA001_05...
Page 18: ...18 Tsi310 User Manual 80B6020_MA001_05...
Page 44: ...2 Bus Operation 44 Tsi310 User Manual 80B6020_MA001_05...
Page 58: ...3 Clocking and Reset Options 58 Tsi310 User Manual 80B6020_MA001_05...
Page 62: ...4 Transaction Ordering 62 Tsi310 User Manual 80B6020_MA001_05...
Page 150: ...5 Configuration Registers 150 Tsi310 User Manual 80B6020_MA001_05...
Page 170: ...6 Signals and Pinout 170 Tsi310 User Manual 80B6020_MA001_05...
Page 190: ...7 JTAG Boundary Scan 190 Tsi310 User Manual 80B6020_MA001_05...
Page 196: ...8 Electrical Characteristics 196 Tsi310 User Manual 80B6020_MA001_05...
Page 200: ...9 Package Information 200 Tsi310 User Manual 80B6020_MA001_05...
Page 202: ...A Ordering Information 202 Tsi310 User Manual 80B6020_MA001_05...
Page 206: ...Index 206 Tsi310 User Manual 80B6020_MA001_05...