Difference between revisions of "83Plus:Ports:09"

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(add more interrupt info)
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=== Read Values ===
 
=== Read Values ===
* Bit 0: Set if an interrupt was generated by recieving a byte.
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* Bit 0: Set if an interrupt was generated by receiving a byte.
 
* Bit 1: Set if an interrupt was generated when a byte can be sent.
 
* Bit 1: Set if an interrupt was generated when a byte can be sent.
* Bit 2: ''unknown''
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* Bit 2: Set if an interrupt was generated due to an error in transmission.
 
* Bit 3: Set if the assist is currently receiving data
 
* Bit 3: Set if the assist is currently receiving data
 
* Bit 4: Set if the assist has read a complete byte (which can be read from [[83Plus:Ports:0A|port 0A]])
 
* Bit 4: Set if the assist has read a complete byte (which can be read from [[83Plus:Ports:0A|port 0A]])
 
* Bit 5: Set if the assist is ready to write data (via [[83Plus:Ports:0D|port 0D]])
 
* Bit 5: Set if the assist is ready to write data (via [[83Plus:Ports:0D|port 0D]])
 
* Bit 6: Set if there was an error during transmission
 
* Bit 6: Set if there was an error during transmission
* Bit 7: ''unknown''
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* Bit 7: Set if the link assist is currently sending a byte.
  
 
=== Write Values ===
 
=== Write Values ===

Revision as of 06:05, 21 August 2005

Synopsis

Port Number: 09h

Function: Link Assist Status

This port gives information on the status of the hardware link assist.

Read Values

  • Bit 0: Set if an interrupt was generated by receiving a byte.
  • Bit 1: Set if an interrupt was generated when a byte can be sent.
  • Bit 2: Set if an interrupt was generated due to an error in transmission.
  • Bit 3: Set if the assist is currently receiving data
  • Bit 4: Set if the assist has read a complete byte (which can be read from port 0A)
  • Bit 5: Set if the assist is ready to write data (via port 0D)
  • Bit 6: Set if there was an error during transmission
  • Bit 7: Set if the link assist is currently sending a byte.

Write Values

None

Comments

This port only exists on the 83+ SE and the 84+.

Credits and Contributions

  • Michael Vincent: Original documentation of the link assist