RM0082
Miscellaneous registers (Misc)
Doc ID 018672 Rev 1
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12.4.15 Auxiliary
clock
synthesizer registers
The Auxiliary clock synthesizers are a group of R/W registers which provide an auxiliary
source clock for some internal target devices: IrDA, UART, MII, and the
RAS IPs.
If y is integer multiple of x, the clock generated will have less jitter.
The output frequency originated from every clock synthesizer is given from the following
equations:
with Y < 4096; X < Y/2; Fin = (ref. Clock synthesizer input frequency table)
For further details, please refer to
Chapter 11: Clock & reset system
.
The clock synthesizer input frequency is detailed in the next table:
[03:01]
amem_clk_sel
3’h0
Memory port-1 source clock definition (ref. next table)
Memory port2 source clock configuration table
Control Bit
Description
3’b000
HCLK (synchronous operating mode) (
.
)
3’b001
PLL1(clock synthesizer should be enable).
3’b010
PLL2 (clock synthesizer should be enable).
3’b011
Ras_clk (programmable logic output
clock).
Note: This clock bypass the memory
clock synthesizer logic.
3’b100-111
Reserved (RFU)
[00]
amem_clk_enb
1’h0
Memory port-1 clock gating functionality:
1’b0: Disable memory clock.
1’b1: Enable memory clock.
Table 169.
AMEM_CFG_CTRL register bit assignments (continued)
AMEM_CFG_CTRL Register
0x050
Bit
Name
Reset
Value
Description
Table 170.
Clock Synthesizer input frequency
Clock synthesizer input frequency
Clock synthesizer
Src. Clk1 PLL1 Src. Clk2 PLL2 Description
IRDA
*
Clock provided from Pll1_clkout
UART
*
Clock provided from Pll1_clkout
MAC
*
Programmable source clock (Ref.
MAC_CFG_REG register description).
F
out
1
Fin
X
Y
----
×
⎝
⎠
⎛
⎞
2
⁄
=
F
out
2
Fin
X
Y
----
×
⎝
⎠
⎛
⎞
=