GPMC
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7.1.3.9.1 GPMC Timing Parameters Formulas
This section intends to help the user to calculate the GPMC timing bit fields values. Formulas are not
listed exhaustively.
The section details:
• NAND Flash Interface Timing Parameters Formulas
• Synchronous NOR Flash Timing Parameters Formulas
• Asynchronous NOR Flash Timing Parameters Formulas
7.1.3.9.1.1 NAND Flash Interface Timing Parameters Formulas
This section lists formulas to use in order to calculate NAND timing parameters. This is the case when
GPMC_CONFIG1_i[11-10] DEVICETYPE = 2h. Table 7-42 details NAND timing parameters.
Table 7-42. NAND Formulas Description Table
Configuration
Unit Description
Parameter
A ns Pulse duration - GPMC_WEn valid time
B ns Delay time - GPMC_CSn valid to GPMC_WEn valid
C ns Delay time - GPMC_BE0n_CLE/GPMC_ADVn_ALE high to GPMC_WEn valid
D ns Delay time - GPMC_AD[15:0] valid to GPMC_WEn valid
E ns Delay time - GPMC_WEn invalid to GPMC_AD[15:0] invalid
F ns Delay time - GPMC_WEn invalid to GPMC_BE0n_CLE/GPMC_ADVn_ALE invalid
G ns Delay time - GPMC_WEn invalid to GPMC_CSn invalid
H ns Cycle time - Write cycle time
I ns Delay time - GPMC_CSn valid to GPMC_OEn valid
J ns Setup time - GPMC_AD[15:0] valid to GPMC_OEn invalid
K ns Pulse duration - GPMC_OEn valid time
L ns Cycle time - Read cycle time
M ns Delay time - GPMC_OEn invalid to GPMC_CSn invalid
The configuration parameters are calculated through the following formulas.
A = (WEOffTime - WEOnTime) * (TimeParaGranularity + 1) * GPMC_FCLK period
B = ((WEOnTime - CSOnTime) * (TimeParaGranularity + 1) + 0.5 * (WEExtraDelay - CSExtraDelay)) *
GPMC_FCLK period
C = ((WEOnTime - ADVOnTime) * (TimeParaGranularity + 1) + 0.5 * (WEExtraDelay - ADVExtraDelay)) *
GPMC_FCLK period
D = (WEOnTime * (TimeParaGranularity + 1) + 0.5 * WEExtraDelay ) * GPMC_FCLK period
E = (WrCycleTime - WEOffTime * (TimeParaGranularity + 1) - 0.5 * WEExtraDelay ) * GPMC_FCLK
period
F = (ADVWrOffTime - WEOffTime * (TimeParaGranularity + 1) + 0.5 * (ADVExtraDelay - WEExtraDelay ) *
GPMC_FCLK period
G = (CSWrOffTime - WEOffTime * (TimeParaGranularity + 1) + 0.5 * (CSExtraDelay - WEExtraDelay ) *
GPMC_FCLK period
H = WrCycleTime * (1 + TimeParaGranularity) * GPMC_FCLK period
I = ((OEOnTime - CSOnTime) * (TimeParaGranularity + 1) + 0.5 * (OEExtraDelay - CSExtraDelay)) *
GPMC_FCLK period
J = ((AccessTime - OEOffTime) * (TimeParaGranularity + 1) - 0.5 * OEExtraDelay)) * GPMC_FCLK period
346
Memory Subsystem SPRUH73H–October 2011–Revised April 2013
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