Architecture
LatticeECP/EC Family Data Sheet
Lattice Semiconductor
Figure 2-16. Memory Core Reset
SET
D
Q
Memory Core
Port A[17:0]
LCLR
Output Data
Latches
SET
D
Q
Port B[17:0]
LCLR
RSTA
RSTB
GSRN
Programmable Disable
For further information about sysMEM EBR block, please see the the list of technical documentation at the end of
this data sheet.
EBR Asynchronous Reset
EBR asynchronous reset or GSR (if used) can only be applied if all clock enables are low for a clock cycle before the
reset is applied and released a clock cycle after the reset is released, as shown in Figure 2-17. The GSR input to the
EBR is always asynchronous.
Figure 2-17. EBR Asynchronous Reset (Including GSR) Timing Diagram
Reset
Clock
Clock
Enable
If all clock enables remain enabled, the EBR asynchronous reset or GSR may only be applied and released after
the EBR read and write clock inputs are in a steady state condition for a minimum of 1/f
(EBR clock). The reset
MAX
release must adhere to the EBR synchronous reset setup time before the next active read or write clock edge.
If an EBR is pre-loaded during configuration, the GSR input must be disabled or the release of the GSR during
device Wake Up must occur before the release of the device I/Os becomes active.
These instructions apply to all EBR RAM and ROM implementations.
Note that there are no reset restrictions if the EBR synchronous reset is used and the EBR GSR input is disabled.
sysDSP Block
The LatticeECP-DSP family provides a sysDSP block, making it ideally suited for low cost, high performance Digital
Signal Processing (DSP) applications. Typical functions used in these applications are Finite Impulse Response
(FIR) filters; Fast Fourier Transforms (FFT) functions, correlators, Reed-Solomon/Turbo/Convolution encoders and
2-14
LATTICE [ LATTICE SEMICONDUCTOR ]
