TK2633: MICROPROCESSOR

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TK2633MICROPROCESSOR INTERFACING

• Programming Techniques

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LOOPING

• The programming technique used to instruct the
  MPU to repeat task.
• Continuous loop
• Conditional loop
• Repeat task until certain conditions are met.
• Some loop include indexing along with counter.
• Indexing pointing or referencing objects with
  sequential numbers, i.e. data in memory are
  accessed by referencing to their memory locations.

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COUNTER

• Counter.
• Counter is constructed by loading a number to any
  register.
• Then use INR or DCR to increment or decrement the
  number respectively.
• Loop is used to update counter value and every
  iteration the number is inspected to check
  whether the number is at maximum or minimum.

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BLOCK DATA TRANSFERS

• In many systems, blocks of information are
  transferred from one place to another in the
  microprocessors memory.
• Transferring Blocks of Bytes.
• Transferring Blocks of Words.

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BLOCK DATA TRANSFERS

• Suppose that a block of 10 bytes of data,
  beginning at memory location 2080H, is
  transferred to a block of memory beginning at
  location 2090H.
• The simplest method, is to use the LDA and STA
  instruction to transfer each byte.
• Long program
• A more efficient way to transfer a block of data
  uses the programmed-loop and counter.

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Flowchart

• Flowchart required to transfer a block of bytes
  from one area of memory to another .

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Transfer 10 bytes of data
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BLOCK DATA TRANSFERS

• The program uses
• the HL register pair to indirectly address the
  source block of data.
• The DE register pair to indirectly address the
  destination block.
• Transfers use the MOV A,M instruction to load the
  accumulator from a source block memory location.
• Next, the STAX D instruction stores the
  accumulator data into a destination block memory
  location.
• The B register functions as a counter in this
  example.

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BLOCK DATA TRANSFERS

• Large- byte block transfer gt256 (FF) bytes?
• Program requires a register pair as the counter.
• Example
• A block of bytes beginning at location 01OOH is
  transferred to a block beginning at location
  2800H.
• The length of this block is 300 (12CH) bytes.

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BLOCK DATA TRANSFERS
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Transferring Blocks of Words

• In certain applications, 16-bit words of data
  must be transferred.

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Transferring Blocks of Words
Main Program
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Transferring Blocks of Words
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BLOCK EXCHANGES

• Block exchanges are similar to block transfers
  except that the data are taken from one block of
  memory and exchanged with the data in a second
  block of memory.
• Their main application is in sorting character
  strings and numeric data.

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Byte Block Exchanges

• Suppose that we must exchange the 80H bytes of
  memory beginning at location 2800H with the 80H
  bytes of memory beginning at location 2880H.

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Byte Block Exchanges
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Word Block Exchanges Exercise

• Suppose that we must exchange the 500H words of
  memory beginning at location 9000H with the 500H
  words of memory beginning at location 9100H.

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Thank youQA