83Plus:Ports:2B

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 03.

Synopsis

Port Number: 2Bh

Function: LCD Delay (15 MHz)(02)

This port works in the same manner 29 does, but only when the calculator is set at 15mhz and if port 20 equals 02. It 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

When Bit 1 is set the effects of speed adjustment port 2E can be seen.

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 2B by 4 and round off. NOTE: The contents of this port should NOT be less than 0Ch or the LCD will no longer update.

Comments

This port is not available on the normal TI-83+. On the normal TI-83+ this port is a shadow of Port 03h.

The effect of this port is only seen if the contents of port 20h equals 02.

Credits and Contributions

• James Montelongo