GPMC
7.1.2.3
GPMC Signal List
The GPMC external interface signals are shown in
Table 7-4. GPMC Signal List
Signal
Type
Description
GPMC_A[27:0]
O
Address outputs
GPMC_AD[15:0]
I/O
Data - multiplexed with Address[16:1] and
Address[27:12]
GPMC_CSn[6:0]
O
Chip selects (active low)
GPMC_CLK
O
(1)
Synchronous mode clock
GPMC_ADVn_ALE
O
Address Valid or Address Latch Enable
depending if NOR or NAND protocol
memories are selected.
GPMC_OEn_REn
O
Output Enable (active low). Also used as
Read Enable (active low) for NAND
protocol memories
GPMC_WEn
O
Write Enable (active low)
GPMC_BE0n_CLE
O
Lower Byte Enable (active low). Also used
as Command Latch Enable for NAND
protocol memories
GPMC_BE1n
O
Upper Byte Enable (active low)
GPMC_WPn
O
Write Protect (active low)
GPMC_WAIT[1:0]
I
External wait signal for NOR and NAND
protocol memories.
GPMC_DIR
O
GPMC.D[15:0] signal direction control
Low during transmit (for write access: data
OUT from GPMC to memory)
High during receive (for read access: data
IN from memory to GPMC)
(1)
GPMC_CLK is also used as a re-timing input. The associated CONF_<module>_<pin>_RXACTIVE bit for the output clock must
be set to 1 to enable the clock input back to the module. It is also recommended to place a 33-ohm resistor in series (close to
the processor) to avoid signal reflections.
255
SPRUH73H – October 2011 – Revised April 2013
Memory Subsystem
Copyright © 2011–2013, Texas Instruments Incorporated