EPXA4 Datasheet, PDF (2/34 Pages) Altera Corporation – Excalibur Devices

Excalibur EPXA4 Devices Errata Sheet
EBI
DPRAM
This section provides further information about errata in the EBI.
1.1 Locked 16-Beat Incrementing Bursts
A locked INCR16 transfer can cause the EBI to read from a peripheral
twice. This can cause erroneous behavior if the peripheral contains read-
sensitive registers.
Work Around
Do not use burst transactions to access read-sensitive peripherals
connected to the EBI.
1.2 EBI Acknowledge Signal
The EBI acknowledge signal, EBI_ACK, functionality results in incorrect
EBI asynchronous mode operation.
Work Around
Do not use the EBI_ACK signal when interfacing to external memory
devices. Instead, use the programmable wait states, via the EBI_BLOCKn
register, for the individual EBI blocks. Also ensure that the SA bit for each
EBI block is cleared. This effectively puts the EBI in synchronous mode.
EBI synchronous mode can be used to interface with synchronous or
asynchronous memories provided that the appropriate number of wait
states is implemented.
This section provides further information about errata in the DPRAM.
2.1 Port A Clocks Are Not Pre-Balanced
If the DPRAM is configured in either a deep (×8) or a wide (×32) mode, the
dp0_2_portaclk and dp1_3_portaclk clock signals are not pre-
balanced. The Quartus^® II fitter is unable to balance locally routed clocks
and generates an error.
Work Around
Promote dp0_2_portaclk or the dp1_3_portaclk signal to a global
signal and recompile the design.
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