DS643 Datasheet, PDF (73/216 Pages) Xilinx, Inc – Soft Direct Memory Access (SDMA) support

LogiCORE IP Multi-Port Memory Controller (v6.06.a)
ECC Testing
To enable testing on the ECC core logic, set C_INCLUDE_ECC_TEST = 1. The ECC Control register (ECCC),
described in ECC Registers, page 67, includes control bits for enabling or disabling the test logic. The following list
describes possible forcing errors combinations. If any other combination is attempted, no errors will be forced on
the data written to memory.
• No bit error forcing
• Force single-bit data errors (ECC Control register (ECCC): FORCE_SE = 1)
• Force double-bit data errors (ECC Control register (ECCC): FORCE_DE = 1)
• Force parity bit errors (ECC Control register (ECCC): FORCE_PE = 1)
• Force single-bit data and single parity field bit errors (ECC Control register (ECCC): FORCE_SE = 1 and
FORCE_PE = 1)
For single-bit error testing, a mask shift register forces single-bit errors on the data written to memory. The data
mask shift register has the least significant single-bit equal to one. When testing is enabled during a memory write,
the shift register clocks the one toward the Most Significant Bit (MSB). You must be careful when trying to predict
the pattern. More memory data beats than expected might be written because the Read_Modify_Write reads a
full “memory cacheline,” merge this with the data sent from the PIM, then write back the entire “memory
cacheline.” This results in a different rotation than you might expect.
For double-bit error testing, a data mask shift register forces double-bit errors on the data written to memory. The
data mask shift register has two adjacent bits equal to one (starting in the two least significant bit positions) and
rotates the “11” pattern in the shift register (towards the two most significant bits) on each memory write.
When parity field bit error testing is enabled, a mask shift register forces single-bit errors on the check bits stored in
memory. The parity mask shift register has the least significant single-bit equal to one and rotates the one (toward
the MSB) on each memory write.
DS643 February 22, 2013
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Product Specification