DM300023 Microchip Technology, DM300023 Datasheet - Page 12

• Manufacturer Part Number: DM300023
• Description: KIT DEMO DSPICDEM SMPS BUCK
• Manufacturer: Microchip Technology
• Series: dsPIC™r

Specifications of DM300023

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 2, Non-Isolated
• Voltage - Input: 7 ~ 15V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: dsPIC30F2020
• Processor To Be Evaluated: dsPIC30F202x/1010
• Interface Type: RS-232
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Voltage - Output: -
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

dsPIC30F1010/202X
33. Module: CPU – DAW.b instruction
EXAMPLE 2:
DS80319D-page 12
L0:daw.b
L1: ....
The Decimal Adjust instruction, DAW.b, may
improperly clear the Carry bit, C (SR<0>), when
executed.
Work around
Check the state of the Carry bit prior to executing
the DAW.b instruction. If the Carry bit is set, set the
Carry bit again after executing the DAW.b
instruction. Example 2 shows how the application
should process the Carry bit during a BCD addition
operation.
.include “p30fxxxx.inc”
.......
mov.b
mov.b
add.b
bra
daw.b
bset.b SR, #C
bra
#0x80, w0
#0x80, w1
w0, w1, w2 ;Perform addition
NC, L0
w2
L1
w2
CHECK CARRY BIT BEFORE
DAW.b
;First BCD number
;Second BCD number
;If C set go to L0
;If not, do DAW and
;set the carry bit
;and exit
34. Module: Sleep Mode
Execution of the Sleep instruction (PWRSAV #0)
may cause incorrect program operation after the
device wakes up from Sleep. The current
consumption during Sleep may also increase
beyond the specifications listed in the device data
sheet.
Work arounds
To avoid this issue, any of the following three work
arounds can be implemented, depending on the
application requirements.
Work around 1:
Ensure that the PWRSAV #0 instruction is located
at the end of the last row of Program Flash
Memory available on the target device and fill the
remainder of the row with NOP instructions.
This can be accomplished by replacing all
occurrences of the PWRSAV #0 instruction with a
function call to a suitably aligned subroutine. The
address( ) attribute provided by the MPLAB
ASM30 assembler can be utilized to correctly align
the instructions in the subroutine. For an
application written in C, the function call would be
GotoSleep( ), while for an assembly language
application,
CALL _GotoSleep.
The Address Error Trap Service Routine software
can then replace the invalid return address saved
on the stack with the address of the instruction
immediately
GotoSleep( ) function call. This ensures that
the device continues executing the correct code
sequence after waking up from Sleep mode.
Example 3
described above, as it would apply to a
dsPIC30F2023 device.
demonstrates
the
following
© 2008 Microchip Technology Inc.
function
the
the
_GotoSleep
call
work
would
around
be
or