Electrical characteristics
STM32F20xxx
Synchronous waveforms and timings
Figure 58 through Figure 61 represent synchronous waveforms and Table 75 through
Table 77 provide the corresponding timings. The results shown in these tables are obtained
with the following FSMC configuration:
● BurstAccessMode = FSMC_BurstAccessMode_Enable;
● MemoryType = FSMC_MemoryType_CRAM;
● WriteBurst = FSMC_WriteBurst_Enable;
● CLKDivision = 1; (0 is not supported, see the STM32F20xxx/21xxx reference manual)
● DataLatency = 1 for NOR Flash; DataLatency = 0 for PSRAM
In all timing tables, the THCLK is the HCLK clock period.
Figure 58. Synchronous multiplexed NOR/PSRAM read timings
tw(CLK)
tw(CLK)
BUSTURN = 0
FSMC_CLK
FSMC_NEx
td(CLKL-NADVL)
FSMC_NADV
FSMC_A[25:16]
Data latency = 0
td(CLKL-NExL)
td(CLKL-NADVH)
td(CLKL-AV)
t d(CLKL-NExH)
td(CLKL-AIV)
td(CLKH-NOEL) td(CLKL-NOEH)
FSMC_NOE
td(CLKL-ADV)
FSMC_AD[15:0]
td(CLKL-ADIV)
tsu(ADV-CLKH)
AD[15:0]
tsu(NWAITV-CLKH)
th(CLKH-ADV)
tsu(ADV-CLKH)
D1
D2
th(CLKH-ADV)
th(CLKH-NWAITV)
FSMC_NWAIT
(WAITCFG = 1b, WAITPOL + 0b)
FSMC_NWAIT
(WAITCFG = 0b, WAITPOL + 0b)
tsu(NWAITV-CLKH)
th(CLKH-NWAITV)
tsu(NWAITV-CLKH)
th(CLKH-NWAITV)
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Doc ID 15818 Rev 9