
Lattice Semiconductor
ORCA ORT42G5 and ORT82G5 Data Sheet
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Table 24. Decoding of SCHAR_CHAN
The receive characterization test mode is entered when SCHAR_ENA=1 and SCHAR_TXSEL=0, In this mode,
one of the channels of SERDES outputs is observed at chip ports as shown in
Table 25. The channel that is
observed is also based on the decoding of SCHAR_CHAN as shown in
Table 25.Table 25. SERDES Receive Characterization Mode
Embedded Core Block RAM
There are two independent memory blocks (labeled A and B) built-into the Embedded ASIC Core (EAC). Each
memory block has a capacity of 4K words by 36 bits. These two memory blocks (also called “slices”) are in addition
to the block RAMs found in the FPGA portion of the ORT82G5.
Although the memory blocks/slices are in the EAC part of the chip, they do not interact with the rest of the EAC cir-
cuits, but are standalone memories designed specically to increase RAM capacity in the ORT82G5 chip. They can
be used by logic implemented in the FPGA portion of the FPSC.
Figure 34 represents one of the two available
memory slices built into the EAC. The index “x” refers to the memory slice (x=A for slice A, x=B for slice B). Each
memory slice is organized into two sections, which are also labeled as A and B. In
Figure 34, SDRAM A is one sec-
tion of slice x, and SDRAM B is another section of slice x. Data can be written to both sections of a slice indepen-
dently. However, a read access can access only one of sections A or B at any given time (CSR_x=0 selects section
A, CSR_x=1 selects section B).
The 36 bits written to or read from the memory slice are composed of 32 bits of data (bits 31:24, 23:16, 15:8, 7:0),
and 4 bits of parity (bits 35,34,33,32). The core performs no parity checking functions. The data read from the
memory is registered so that it works as a pipelined synchronous memory block.
For illustration purposes, assuming that the memory slice in
Figure 34 is slice A (x=A), then certain signals apply to
both sections of slice A. These include D_A[35:0], CKW_A, AW_A[10:0], BYTEWN_A[3:0], Q_A[35:0], CKR_A,
CSR_A, and AR_A[10:0]. The BYTEWN_A[3:0] are byte and parity write enable bits for each byte and parity bit of
data being written.
BYTEWN_A[3] is associated with D_A[35,31:24].
BYTEWN_A[2] is associated with D_A[34,23:16].
BYTEWN_A[1] is associated with D_A[33,15:8].
BYTEWN_A[0] is associated with D_A[32,7:0].
The signals that are unique to each section of slice A are:
CSWA_A --enables writing to section A of slice A
CSWB_A -- enables writing to section B of slice A
SCHAR_CHAN0
SCHAR_CHAN1
Channel
0
BA
1
0
BB
0
1
BC
1
BD
SERDES Output
Chip Port
BYTSYNCBx
PSCHAR_BYTSYNC
WDSYNCBx
PSCHAR_WDSYNC
CVOBx
PSCHAR_CV
LDOUTBx[9:0]
PSCHAR_LDIO[9:0]
RBC0Bx
PSCHAR_CKIO0
RBC1Bx
PSCHAR_CKIO1