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GPMC
7.1.3.3.10.1.2.2 Asynchronous Single Read on an AAD-Multiplexed Device
See Section 7.1.3.9.1 for formulas to calculate timing parameters.
Table 7-41 lists the timing bit fields to set up in order to configure the GPMC in asynchronous single write
mode.
When the GPMC generates a read access to an AAD-multiplexed device, all address bits are driven onto
the address/data bus in two separate phases. The first phase is used for the MSB address and is qualified
with OEn driven low. The first address phase ends at the first OEn deassertion time. The second phase
for LSB address is qualified with OEn driven high. The second address phase ends at the second OEn
assertion time, when the DIR signal goes from OUT to IN.
The CSn and DIR signals are controlled in the same way as for asynchronous single read operation on an
address/data-multiplexed device.
• Address valid signal ADVn. ADVn is asserted and deasserted twice during a read transaction:
– ADVn first assertion time is controlled by the GPMC_CONFIG3_i[6-4] ADVAADMUXONTIME field.
– ADVn first deassertion time is controlled by the GPMC_CONFIG3_i[26-24]
ADVAADMUXRDOFFTIME field.
– ADVn second assertion time is controlled by the GPMC_CONFIG3_i[3-0] ADVONTIME field.
– ADVn second deassertion time is controlled by the GPMC_CONFIG3_i[12-8] ADVRDOFFTIME
field.
• Output Enable signal OEn. OEn is asserted and deasserted twice during a read transaction (OEn
second assertion indicates a read cycle):
– OEn first assertion time is controlled by the GPMC_CONFIG4_i[6-4] OEAADMUXONTIME field.
– OEn first deassertion time is controlled by the GPMC_CONFIG3_i[15-13] OEAADMUXOFFTIME
field.
– OEn second assertion time is controlled by the GPMC_CONFIG4_i[3-0] OEONTIME field.
– OEn second deassertion time is controlled by the GPMC_CONFIG4_i[12-8] OEOFFTIME field.
285
SPRUH73H–October 2011–Revised April 2013 Memory Subsystem
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