RM0082
RS_Flexible static memory controller (FSMC)
Doc ID 018672 Rev 1
669/844
31.4.6 GenMemCtrl_tim(i)
registers
Each GenMemCtrl_tim(i) (with i = 0...3) is a RW register which contains the timing control
information of each bank used for SRAMs and NOR Flash memories. The
GenMemCtrl_tim(i) bit assignments are given in
.
Note:
For information on programming the timing register, refer
Section 31.4.12: Calculating the
FSMC timing parameters on page 673
[01]
Muxed
1'h1
Muxed memory. This bit allows to enable muxed memory to use
the data bus to get the addresses, according to the encoding
below:
0 - Not muxed.
1 - Muxed (Not used in
SPEAr300
)
[00]
BankEnable -
Enable bank. This bit allows to enable/disable the relevant bank,
according to the encoding below:
0 - Disabled.
1 - Enabled.
After reset Bank 0 is enabled and all the others are disabled.
Accessing a disabled bank causes a HRESP to be ERROR on
AHB.
A NOR Flash memory that is in reset-power down
(RstPowerDown = 'b0), is considered disabled, even if the
BankEnable bit is 'b1. It follows that accessing the memory in
such condition causes a HRESP to be ERROR on AHB.
Table 597.
GenMemCtrl(i) register bit assignments (continued)
Bit
Name
Reset
value
Description
Table 598.
GenMemCtrl_tim(i) register bit assignments
Bit
Name
Reset
value
Description
[31:20]
-
-
Read: undefined. Write: should be zero.
[19:16]
BusTurn
4’hF
Bus turn around duration. This 4-bit field indicates the bus turn
around duration (HCLK 1). Each time the FSMC ends a
memory read, a single access or the last of a burst, it enters the
bus turn around state, and it starts to count the HCLK cycles
specified in this field.
[15:08]
Data_st
8’hFF
Duration of Data_st phase. This 8-bit field indicates the duration
of "Data_st" phase (HCLK 1). This value cannot be 8'h0,
its minimum value must be 8'h01. This field is applicable to all
memory types.
[07:04]
Hold_addr
4’hF
Duration of Hold_addr phase. This 4-bit field indicates the
duration of "Hold_addr" phase (HCLK 1). This field is
applicable to SRAMs.
[03:00]
AddrST
4’hF
Duration of address state phase. This 4-bit field indicates the
duration of “Address state” phase, expressed as (HCLK
1). This field is applicable to NOR Flash.