Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

UPD784938 Datasheet(PDF) 84 Page - NEC

Part # UPD784938
Description  16-Bit Single-Chip Microcontrollers
Download  733 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  NEC [NEC]
Direct Link  http://www.nec.com/
Logo NEC - NEC

UPD784938 Datasheet(HTML) 84 Page - NEC

Back Button UPD784938 Datasheet HTML 80Page - NEC UPD784938 Datasheet HTML 81Page - NEC UPD784938 Datasheet HTML 82Page - NEC UPD784938 Datasheet HTML 83Page - NEC UPD784938 Datasheet HTML 84Page - NEC UPD784938 Datasheet HTML 85Page - NEC UPD784938 Datasheet HTML 86Page - NEC UPD784938 Datasheet HTML 87Page - NEC UPD784938 Datasheet HTML 88Page - NEC Next Button
Zoom Inzoom in Zoom Outzoom out
 84 / 733 page
background image
84
CHAPTER 3 CPU ARCHITECTURE
Preliminary User’s Manual U13987EJ1V0UM00
(2) Parity/overflow flag (P/V)
The P/V flag performs the following two kinds of operation associated with execution of an operation instruction.
The status of the P/V flag can be tested with a conditional branch instruction.
• Parity flag operation
Set (to 1) when the number of bits set (to 1) as the result of execution of a logical operation instruction, shift/rotate
instruction, or a CHKL or CHKLA instruction is even, and reset (to 0) if odd. When a 16-bit shift instruction is executed,
however, only the low-order 8 bits of the operation result are valid for the parity flag.
• Overflow flag operation
Set (1) only when the numeric range expressed as a two’s complement is exceeded as the result of execution of a
arithmetic operation instruction, and reset (to 0) otherwise. More specifically, the value of this flag is the exclusive OR
of the carry into the MSB and the carry out of the MSB. For example, the two’s complement range in an 8-bit arithmetic
operation is 80H (–128) to 7FH (+127), and the flag is set (to 1) if the operation result is outside this range, and reset (to
0) if within this range.
Example The operation of the overflow flag when an 8-bit addition instruction is executed is shown below.
When the addition of 78H (+120) and 69H (+105) is performed, the operation result is E1H (+225), and the two’s
complement limit is exceeded, with the result that the P/V flag is set (to 1). Expressed as a two’s complement,
E1H is -31.
78H (+120)
=
0111
1000
+)
69H (+105)
= +)
0110
1001
0
1110
0001
=
–31
P/V = 1
CY
When the following two negative numbers are added together, the operation result is within the two’s
complement range, and therefore the P/V flag is reset (to 0).
FBH (–5)
=
1111
1011
+)
F0H (–16)
= +)
1111
0000
1
1110
1011
=
–21
P/V = 0
CY
(3) Interrupt request enable flag (IE)
This flag controls CPU interrupt request acknowledgment operations.
When “0”, interrupts are disabled, and only non-maskable interrupts and unmasked macro service can be acknowledged.
All other interrupts are disabled.
When “1”, the interrupt enabled state is set, and enabling of interrupt request acknowledgment is controlled by the interrupt
mask flags corresponding to the individual interrupt requests and the priority of the individual interrupts.
The IE flag is set (to 1) by execution of an EI instruction, and reset (to 0) by execution of a DI instruction or acknowledgment
of an interrupt.


Similar Part No. - UPD784938

ManufacturerPart #DatasheetDescription
logo
NEC
UPD784938A NEC-UPD784938A Datasheet
371Kb / 52P
   16-BIT SINGLE-CHIP MICROCONTROLLER
logo
Renesas Technology Corp
UPD784938AGF-XXX-3BA RENESAS-UPD784938AGF-XXX-3BA Datasheet
692Kb / 104P
   MOS INTEGRATED CIRCUITS
2001
More results

Similar Description - UPD784938

ManufacturerPart #DatasheetDescription
logo
Renesas Technology Corp
UPD78F1502AGK-GAK-AX RENESAS-UPD78F1502AGK-GAK-AX Datasheet
6Mb / 1031P
   16-Bit Single-Chip Microcontrollers
logo
NEC
UPD784214A NEC-UPD784214A Datasheet
561Kb / 50P
   16-BIT SINGLE-CHIP MICROCONTROLLERS
UPD784915A NEC-UPD784915A Datasheet
446Kb / 86P
   16-BIT SINGLE-CHIP MICROCONTROLLERS
UPD784915B NEC-UPD784915B Datasheet
384Kb / 86P
   16-BIT SINGLE-CHIP MICROCONTROLLERS
UPD784224 NEC-UPD784224 Datasheet
687Kb / 92P
   16/8-BIT SINGLE-CHIP MICROCONTROLLERS
logo
Siemens Semiconductor G...
C167CR-16RM SIEMENS-C167CR-16RM Datasheet
1Mb / 67P
   16-Bit CMOS Single-Chip Microcontrollers
logo
NEC
UPD78363A NEC-UPD78363A Datasheet
502Kb / 96P
   16/8-BIT SINGLE-CHIP MICROCONTROLLERS
UPD784035Y NEC-UPD784035Y Datasheet
503Kb / 94P
   16-/8-BIT SINGLE-CHIP MICROCONTROLLERS
UPD784218 NEC-UPD784218 Datasheet
617Kb / 92P
   16-/8-BIT SINGLE-CHIP MICROCONTROLLERS
logo
Siemens Semiconductor G...
C161V SIEMENS-C161V_96 Datasheet
3Mb / 260P
   16-Bit CMOS Single-Chip Microcontrollers
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100  ...More


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com