Difference between revisions of "83Plus:Ports:29"
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'''Function:''' LCD Delay (6 MHz) | '''Function:''' LCD Delay (6 MHz) | ||
| − | This port removes the amount of delay needed between accesses to the | + | This port removes the amount of delay needed between accesses to the LCD driver by adding a delay to any instruction which reads from or writes to ports [[83Plus:Ports:10|10]] or [[83Plus:Ports:11|11]], as well as the mirror ports 12 and 13. |
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=== Usage === | === Usage === | ||
| − | Bits 0 | + | Bits 0 and 1 are unknown, but don't seem to directly remove the needed delay. On the 83+SE these are reset, on the 84+(SE) these are set. |
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| + | Bits 2-7 control the amount of delay added at specified instructions. To calculate the number of clock cycles added, divide the contents of port 29 by 4 and round off. | ||
== Comments == | == Comments == | ||
Revision as of 13:48, 8 August 2005
| This port only exists as a distinct port on the TI-83 Plus Silver Edition, the TI-84 Plus, and the TI-84 Plus Silver Edition. On the standard TI-83 Plus, it acts as a shadow of port 01. |
Synopsis
Port Number: 29h
Function: LCD Delay (6 MHz)
This port removes the amount of delay needed between accesses to the LCD driver by adding a delay to any instruction which reads from or writes to ports 10 or 11, as well as the mirror ports 12 and 13.
Usage
Bits 0 and 1 are unknown, but don't seem to directly remove the needed delay. On the 83+SE these are reset, on the 84+(SE) these are set.
Bits 2-7 control the amount of delay added at specified instructions. To calculate the number of clock cycles added, divide the contents of port 29 by 4 and round off.
Comments
This port is not available on the normal TI-83+. On the normal TI-83+ this port is a shadow of Port 01h.
Bits 0&1 seem to tie to port 2E, they affect the cpu speed reduction the port 2e contorls. Though their exact purpose is not known.
