ADSP-21368 SHARC Processor Hardware Reference 14-29
System Design
To determine switching frequencies for the serial ports, divide down the
internal clock, using the programmable divider control of each port (
DIVx
for the serial ports). For the SPI port, the BAUDR bit in the SPICTL register
controls the SPICLK baud rate based on the core clock frequency.
Note the following definition and Figure 14-8 for various clock periods
that are functions of
CLKIN and the appropriate ratio control:
CCLK = core clock = PLLICLK × PLL multiply ratio (determined by CLK_CFG
pins)
Programs can modify this setting using bits in the
PMCTL register. For more
information, see “Power Management Control Register (PMCTL)” on
page A-170.
L
Performing a hard reset on the processor also resets the PLL.
Figure 14-7. Reset Generator and Power Supply Monitor
RESET
NMI
IRQx
FLAGx
GND
RESET
V
DDEXT
PFI
OSCSEL
PFO
WDI
WDO
4
8
7
15
11
14
ADM8697
V
CC
9
RST
10
DDEXT
+
.
a
ADSP-213xx
S
3
15
OSCIN
GND TST
LL
W
NC
3.3V
V
t
>1.3V
V
t
>1.3V
V
LINE SENSE