PWRM_changeSetpoint
2-310
C Interface
Syntax
status = PWRM_changeSetpoint(newSetpoint, notifyTimeout);
Parameters
Uns
newSetpoint; /* new V/F setpoint */
Uns
notifyTimeout; /* maximum time to wait for notification */
Return Value
PWRM_Status status;
/* returned status */
Reentrant
yes
Description
PWRM_changeSetpoint changes the voltage and frequency of the DSP
CPU. Reducing the clock rate (frequency) results in a linear decrease in
power consumption. Reducing the operating voltage results in a
quadratic reduction in power consumption. Note that there are issues you
should be aware of when reducing the clock frequency. For a discussion
of these issues, see the
TMS320 DSP/BIOS User’s Guide
(SPRA423).
The newSetpoint parameter is a numeric value that indexes into a table
of frequency/voltage pairs, as defined by the underlying PSL library. For
example, the following table shows the setpoints for the ’C5509A EVM.
PWRM_changeSetpoint
Initiate a change to the V/F setpoint
Setpoint
’C5509A EVM Frequency (MHz)
’C5509A EVM Voltage (volts)
15
192
1.6
14
180
1.6
13
168
1.6
12
156
1.6
11
144
1.4
10
132
1.4
9
120
1.4
8
108
1.2
7
96
1.2
6
84
1.2
5
72
1.2
4
60
1.2
3
48
1.2
2
12
1.2
1
6
1.2
0
3
1.2
