Miscellaneous registers (Misc)
RM0082
220/844
Doc ID 018672 Rev 1
12.4.6 PLL1/2_FRQ
registers
The PLL1/2_FRQ are R/W registers used to configure the PLL VCO frequency operating
mode. The register bit assignments is given in the next table.
[01]
pll_resetn
1’h0
PLL soft reset command:
1’b0: PLL active reset command.
1’b1: PLL reset enable.
[00]
pll_lock
1’h0
PLL Lock Status (RO); field meaningful when PLL is configured
in normal mode:
1’b0: PLL unlock status.
1’b1: PLL lock active status.
Table 160.
PLL 1/2_CTR register bit assignments (continued)
PLL_CTR Register
PLL2_CTR
0x008
0x014
Bit
Name
Reset
Value
Description
Table 161.
PLL1/2_FRQ register bit assignments
PLL1_FRQ Register
PLL2_FRQ
0x00C
0x018
Bit
Name
Reset
Value
Description
[31:16]
pll_fbkdiv_M
16’h
A600
(
.
)
M[15:0]: PLL feedback divisor values; when PLL is
configured in normal mode only M[15:8] upper byte is
considered.
Two different equations are provided for the VCO frequency
definition which must be programmed within range from 200
MHz min. to 800 MHz max as detailed below:
PLL Normal mode configuration
M[15:8] can assume the following range of values:
with 200 < f
VCD
< 800 MHz; f
ref
24 MHz.
PLL dithered or fractional-N mode configurations:
[15:0] can assume the following range of values:
with 200 < f
VCD
< 800 MHz; f
ref
24 MHz.
[15:11]
RFU
-
Reserved for future use (Write don’t care - Read return
zeros).
f
VCD
2
f
ref
•
M
15 8
;
[
]
•
=
4
M
17
<
<
f
VCD
2
f
ref
•
256
-----------------
M
•
=
1066
M
4266
<
<