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GR716-DS-UM, May 2019, Version 1.29
94
www.cobham.com/gaisler
GR716
10.3
Registers
Table 78.
PLL control and status registers
APB address offset
Register
0x00
Configuration register
0x04
Status register
0x08
PLL reference clock and divider
0x0C
Select SpaceWire clock source and divisor
0x10
Select 1553B clock source and divisor
0x14
Select SYS clock source and divisor
0x18
Switch to selected system clock
0x1C
Control register
0x20
Protection register
0x24
Test clock enable
0x28
Select PWM0 clock source and divisor
0x2C
Select PWM1 clock source and divisor
Table 79.
0x00 - CFG - PLL configuration registers
31 30
3
2
0
0
PD
RESERVED
CFG
0*
0x00000000
0*
rw
r
rw
31
PLL power down (PD) - If this bit is written to 1, the PLL is powerdown. The PLL should always be in power
down mode when not used, i.e.,when the PLL is bypassed.
30: 3
RESERVED
2: 0
PLL configuration (CFG) - Internal PLL multiplier depended upon the input frequency of the PLL
011b - when input frequency 25MHz (division by 16)
101b - when input frequency 20MHz(division by 20)
100b - when input frequency 12.5MHz(division by 32)
110b - when input frequency 10MHz (division by 40)
111b - when input frequency 5MHz (division by 80)
000b - not used
001b - not used
* This register can be changed after reset due to bootstrap pins
Table 80.
0x04 - STS - PLL status register
31
2
1
0
RESERVED
LL CL
0x00000000
wc
-
r
rw
r
31: 2
RESERVED
1
Lost lock (LL) - This bit is a sticky bit that indicates if the lock bit from the SpaceWire clock PLL has gone low.
This bit can be cleared by writing a 1 to the PLL clear lost lock bit.
0
PLL clock lock (CL) - Shows the current value of the PLL lock output.