ADuCM320 Hardware Reference Manual
UG-498
Rev. C | Page 15 of 196
Bits Bit
Name
Description
Reset Access
1 UCLKSPI1OFF SPI1 clock user control. This bit disables the UCLK_SPI1 clock. It controls
the gate on UCLK_SPI1 in Power Mode 0 and Power Mode 1. In Power Mode 2
and Power Mode 3 the UCLK_SPI1 is always off and this bit has no effect.
0x0 RW
0: clock on
1: clock off
0 UCLKSPI0OFF SPI0 clock user control. This bit disables the UCLK_SPI0 clock. It controls
the gate on UCLK_SPI0 in Power Mode 0 and Power Mode 1. In Power Mode 2
and Power Mode 3, the UCLK_SPI0 is always off and this bit has no effect.
0x0 RW
0: clock on
1: clock off
Clocking Status Register
Address: 0x40028018, Reset: 0x0000, Name: CLKSTAT0
The clock status register is used to monitor PLL and oscillator status.
Table 8. Bit Descriptions for CLKSTAT0
Bits
Bit Name
Description
Reset
Access
15
RESERVED
Reserved. Always returns 0 when read.
0x0
R
14 HFXTALNOK HF crystal not stable. This bit is sticky. It is used to interrupt the core when interrupts are enabled.
Write a 1 to this location to clear it.
0x0 RW
0: HF crystal stable signal has not been deasserted.
1: HF crystal stable signal has been deasserted.
13 HFXTALOK HF crystal stable. This bit is sticky. It is used to interrupt the core when interrupts are enabled.
Write a 1 to this location to clear it.
0x0 RW
0: HF crystal stable signal has not been asserted.
1: HF crystal stable signal has been asserted.
12
HFXTALSTATUS
HF crystal status.
0x0 R
0: HF crystal is not stable or not enabled.
1: HF crystal is stable.
[11:3] RESERVED
Reserved.
0x0 R
2 SPLLUNLOCK
System PLL unlock. This bit is sticky. SPLLUNLOCK is set when the PLL loses its lock.
SPLLUNLOCK is used as the interrupt source to signal the core that a lock was lost. Writing a 1
to this bit clears it. SPLLUNLOCK does not set again unless the system PLL gains a lock and
subsequently loses it again.
0x0 RW
0: no loss of PLL lock was detected.
1: a PLL loss of lock was detected.
1 SPLLLOCK System PLL lock. This bit is sticky. SPLLLOCK is set when the PLL locks. SPLLLOCK is used as the
interrupt source to signal the core that a lock was detected. Writing a 1 to this bit clears it.
SPLLLOCK does not set again unless the system PLL loses lock and subsequently locks again.
0x0 RW
0: no PLL lock event was detected.
1: a PLL lock event was detected.
0 SPLLSTATUS
System PLL status. Indicates the current status of the PLL. Initially the system PLL is unlocked.
After a stabilization period, the PLL locks and is ready for use as the system clock source. This is
a read only bit. A write has no effect.
0x0 R
0: the PLL is not locked or not properly configured. The PLL is not ready for use as the system
clock source.
1: the PLL is locked and is ready for use as the system clock source.