Emerson MVME2500 Manuel D’Utilisation
Programming Model
MVME2500 Installation and Use (6806800L01H)
121
7.7
Clock Distribution
The clock function generates and distributes all of the clocks required for system operation.
The ICS9FG108 is used to generate all the required PCI-E clocks. The 25 MHz clocks for the
Ethernet PHY and SATA bridge are supplied by ICS83905. Most of the QorIQ P2020 clocks are
generated by ICS840S07I chip. Additional clocks required by individual devices are generated
near the devices using individual oscillators. The following table lists the clocks required on the
MVME2500 along with the frequency and source.
The ICS9FG108 is used to generate all the required PCI-E clocks. The 25 MHz clocks for the
Ethernet PHY and SATA bridge are supplied by ICS83905. Most of the QorIQ P2020 clocks are
generated by ICS840S07I chip. Additional clocks required by individual devices are generated
near the devices using individual oscillators. The following table lists the clocks required on the
MVME2500 along with the frequency and source.
SETA
External address termination
0 - Access is terminated internally by the memory controller unless the
external device asserts LGTA earlier to terminate the access.
0 - Access is terminated internally by the memory controller unless the
external device asserts LGTA earlier to terminate the access.
TRLX Timing
Relaxed
0 - Normal timing is generated by the GPCM.
EHTR
Extended hold time on read accesses.
0 - The memory controller generates normal timing. No additional cycles
are inserted
0 - The memory controller generates normal timing. No additional cycles
are inserted
EAD
External address latch delay
0 - No additional bus clock cycles (LALE asserted for one bus clock cycle
only)
0 - No additional bus clock cycles (LALE asserted for one bus clock cycle
only)
Table 7-6 Clock Distribution
Device
Clock Signal
Frequency
Clock Tree Source
VIO
QorIQ P20x0
CPU_SYSCLK
100MHz
ICS840S07I
+3.3V
QorIQ P20x0
CPU_DDR_CLK
100MHz
ICS840S07I
+3.3V
QorIQ P20x0
CLK_PCI_BR3
133Mhz
ICS840S07I
+3.3V
QorIQ P20x0
EC_GTX_CLK125
125Mhz
ICS840S07I
+3.3V
ICS840S07I
CLK_25MHZ_ICS840S07
25Mhz
ICS83905AGILF
+3.3V
88SE6121
CLK_88SE6121_25MHZ
25Mhz
ICS83905AGILF
+3.3V
ICS9FG108
CLK_25MHZ_ICS9FG108
25Mhz
ICS83905AGILF
+3.3V
BCM54616S
BP_PHY_25MHZ_CLK
25Mhz
ICS83905AGILF
+3.3V
BCM54616S
FP_PHY_25MHZ_CLK
25Mhz
ICS83905AGILF
+3.3V