
TAMC900 User Manual Issue 2.0.1
Page 51 of 71
13 On Board CPLD
The On Board CPLD of the TAMC900 is used for static board configuration and provides the following
functions:
•
QDR-II SRAM DLL enable / disable
•
ADC
Shutdown
•
ADC Output Enable
•
ADC Mode selection (all 4 modes available)
•
Control of 16 GP I/O pins to the SiCA.
•
Enabling / disabling of the local FPGA clock
•
Controlling of the jitter attenuator
•
Control of the local clock distribution
Please refer to the following subsections for more information.
13.1
Interface to FPGA
All functions of the CPLD are accessible by the User FPGA via an easy to use interface. The clock is
driven by the CPLD. Per default this is set to 25 MHz. It can be set to 12.5 MHz if necessary.
Clock
Address[4:0]
Read#
Write#
Data[7:0]
Write
to CPLD
Valid
Address
Valid
Address
Valid
Data
Valid
Data
Read
from CPLD
Figure 13-1: Timing of FPGA-CPLD Interface