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GR716-DS-UM, May 2019, Version 1.29
99
www.cobham.com/gaisler
GR716
r
rw
r
rw
rw
31: 25
RESERVED
24
Divide reference clock by 2. To generate a 200 MHz clock the PWM0REF.SEL must be set to 0x3 i.e. the source
of the PWM clock must be the output of the PLL.
23: 16
DUTY cycle for generated clock frequency - The duty cycle bitfield specifies how many of the total clock cycles
specified in the DIV bitfield the generated clock shall be high. IF this register is set to 0x0 the duty cycle will be
set to clock cycles defined in DIV and the clock period to 2xDIV.
15: 10
RESERVED
9: 8
PWM Reference Clock (SEL) - Select 1553B reference clock and source
0x0 - Clock source from external signal SYS_CLK
0x1 - Clock source from external signal SPW_CLK
0x2 - External PWM0 clock pin GPIO[17]
0x3 - Clock generated from PLL
7: 0
PWM reference Clock Divisor (DIV) - Set the divisor for input reference clock. Zero (default) bypass the divi-
sor.
When bitfield DUTY period is set to 0x0. The input clock frequency will be divided by 2xDIV clock cycles with
the duty cycle set to 50%
When bitfield DUTY period is larger then 0x1.The DIV bifield will divide the input frequency by DIV clock
cycles and with the duty cycle defined in the DUTY bitfield
Table 90.
0x2C - PWM1REF - Select reference for PWM1 clock
31
24 23
16 15
10
9
8
7
0
RESERVED
D2
DUTY
RESERVED
SEL
DIV
0x0
0x0
0x0
0
0
r
rw
r
rw
rw
31: 25
RESERVED
24
Divide reference clock by 2. To generate a 200 MHz clock the PWM1REF.SEL must be set to 0x3 i.e. the source
of the PWM clock must be the output of the PLL.
23: 16
DUTY cycle for generated clock frequency - The duty cycle bitfield specifies how many of the total clock cycles
specified in the DIV bitfield the generated clock shall be high. IF this register is set to 0x0 the duty cycle will be
set to clock cycles defined in DIV and the clock period to 2xDIV.
15: 10
RESERVED
9: 8
PWM Reference Clock (SEL) - Select 1553B reference clock and source
0x0 - Clock source from external signal SYS_CLK
0x1 - Clock source from external signal SPW_CLK
0x2 - External PWM0 clock pin GPIO[18]
0x3 - Clock generated from PLL
7: 0
PWM reference Clock Divisor (DIV) - Set the divisor for input reference clock. Zero (default) bypass the divi-
sor.
When bitfield DUTY period is set to 0x0. The input clock frequency will be divided by 2xDIV clock cycles with
the duty cycle set to 50%
When bitfield DUTY period is larger then 0x1.The DIV bifield will divide the input frequency by DIV clock
cycles and with the duty cycle defined in the DUTY bitfield
Table 89.
0x28 - PWM0REF - Select reference for PWM0 clock