GPMC_FCLK
GPMC_CLK
nBE1/nBE0
nCS
nADV
nOE
DIR
WAIT
Valid Address
Valid Address
Data 0
Data 0
OUT
IN
OUT
CSONTIME
CSRDOFFTIME
ADVONTIME
ADVRDOFFTIME
OEONTIME
OEOFFTIME
RDACCESSTIME
RDCYCLETIME
A[27:17]
A[16:1]/D[15:0]
GPMC
7.1.3.3.10.1.1 Access on Address/Data Multiplexed Devices
7.1.3.3.10.1.1.1 Asynchronous Single-Read Operation on an Address/Data Multiplexed Device
shows an asynchronous single read operation on an address/data-multiplexed device.
Figure 7-12. Asynchronous Single Read Operation on an Address/Data Multiplexed Device
7.1.3.3.10.1.1.2 Asynchronous Single Read on an Address/Data-Multiplexed Device
See
for formulas to calculate timing parameters.
lists the timing bit fields to set up in order to configure the GPMC in asynchronous single read
mode.
When the GPMC generates a read access to an address/data-multiplexed device, it drives the address
bus until OEn assertion time. For details, see
.
Address bits (A[16:1] from a GPMC perspective, A[15:0] from an external device perspective) are placed
on the address/data bus, and the remaining address bits GPMC_A[25:16] are placed on the address bus.
The address phase ends at OEn assertion, when the DIR signal goes from OUT to IN.
•
Chip-select signal CSn
–
CSn assertion time is controlled by the GPMC_CONFIG2_i[3-0] CSONTIME field. It controls the
address setup time to CSn assertion.
–
CSn deassertion time is controlled by the GPMC_CONFIG2_i[12-8] CSRDOFFTIME field. It
controls the address hold time from CSn deassertion
•
Address valid signal ADVn
–
ADVn assertion time is controlled by the GPMC_CONFIG3_i[3-0] ADVONTIME field.
–
ADVn deassertion time is controlled by the GPMC_CONFIG3_i[[12-8] ADVRDOFFTIME field.
281
SPRUH73H – October 2011 – Revised April 2013
Memory Subsystem
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