83Plus:Ports:2E - Revision history

NonstickAtom: More info from the_mad_joob. Maybe consider making him an account :D.

2020-12-09T18:17:22Z

More info from the_mad_joob. Maybe consider making him an account :D.

Thepenguin77 at 03:50, 28 October 2011

2011-10-28T03:50:06Z

Thepenguin77 at 03:11, 28 October 2011

2011-10-28T03:11:00Z

Dan Englender: English

2006-03-14T04:28:02Z

English

Jim e: Always spellcheck

2006-03-12T18:37:26Z

Always spellcheck

Jim e: Rewrote with new info.

2006-03-12T18:36:44Z

Rewrote with new info.

68.3.161.239: /* Synopsis */

2005-08-23T05:28:28Z

‎Synopsis

Jim e: Added info from lcd delay ports

2005-08-22T11:51:06Z

Added info from lcd delay ports

Jim e: Forgot comment, plus defualt vaule 44h for 83se.

2005-08-11T10:50:33Z

Forgot comment, plus defualt vaule 44h for 83se.

Jim e: Port 0E is a shadow of 06

2005-08-11T10:48:06Z

Port 0E is a shadow of 06

@@ Line 28: / Line 28: @@
 == Comments ==
-Why this port is necessary is unknown, however it is set to 44 on the 83+SE and 45 on the 84+(SE).
+With bits 0 & 4, extra clock cycle are doubled if the instruction is prefixed.
-This port is not available on the normal TI-83+. On the normal TI-83+ this port is a shadow of [[83Plus:Ports:06|Port 06h]].
+Why this port is necessary is unknown, however it is set to 44 on the 83+SE and 45 on the 84+(SE).
@@ Line 38: / Line 40: @@
 * '''James Montelongo'''
 * '''Ben Moody'''

@@ Line 1: / Line 1: @@
 [[Category:83Plus:Ports:By Address|2E - Memory Access Delay]] [[Category:83Plus:Ports:By Name|Memory Access Delay]]
-{{SE-Only Port|0E}}
+{{SE-Only Port|06}}
 == Synopsis ==

@@ Line 1: / Line 1: @@
 [[Category:83Plus:Ports:By Address|2E - Memory Access Delay]] [[Category:83Plus:Ports:By Name|Memory Access Delay]]
-{{SE-Only Port|06}}
+{{SE-Only Port|0E}}
 == Synopsis ==

← Older revision		Revision as of 04:28, 14 March 2006
Line 7:		Line 7:
	'''Function:''' Memory Access Delay		'''Function:''' Memory Access Delay

−	This port will add a 1 cycle delay for certain types of reads for the ram or the flash. This port's ~~affect~~ is enabled by the lcd delay port currently selected by the current CPU speed.	+	This port will add a 1 cycle delay for certain types of reads for the ram or the flash. This port's effect is enabled by the lcd delay port currently selected by the current CPU speed.

@@ Line 1: / Line 1: @@
-[[Category:83Plus:Ports:By Address|2E - Memmory Access Delay]] [[Category:83Plus:Ports:By Name|Memmory Access Delay]]
+[[Category:83Plus:Ports:By Address|2E - Memory Access Delay]] [[Category:83Plus:Ports:By Name|Memory Access Delay]]
 {{SE-Only Port|06}}
@@ Line 5: / Line 5: @@
 '''Port Number:''' 2Eh
-'''Function:''' Memmory Access Delay
+'''Function:''' Memory Access Delay
 This port will add a 1 cycle delay for certain types of reads for the ram or the flash. This port's affect is enabled by the lcd delay port currently selected by the current CPU speed.
@@ Line 11: / Line 11: @@
 ==To enable by the LCD Ports==
-* Bit 0 of the LCD ports (depending on current CPU speed mode) enable the effects of the flash delay controled be 2E.
+* Bit 0 of the LCD ports (depending on current CPU speed mode) enable the effects of the flash delay controlled be 2E.
-* Bit 1 of the LCD ports (depending on current CPU speed mode) enable the effects of the ram delay controled be 2E.
+* Bit 1 of the LCD ports (depending on current CPU speed mode) enable the effects of the ram delay controlled be 2E.
@@ Line 19: / Line 19: @@
 ** Bit 0 adds a clock for every opcode read from the flash.
 ** Bit 1 adds a clock for every non-opcode read from the flash.
-** Bit 2 adds a clock for every (attemped) write to the flash.
+** Bit 2 adds a clock for every (attempted) write to the flash.
 * Bits 4-6 of port 2E affect the ram reads and writes.
 ** Bit 4 adds a clock for every opcode read from the ram.
@@ Line 28: / Line 28: @@
 == Comments ==
-Why this port is nesscary is unknown, however it is set to 44 on the 83+SE and 45 on the 84+(SE).
+Why this port is necessary is unknown, however it is set to 44 on the 83+SE and 45 on the 84+(SE).
 This port is not available on the normal TI-83+. On the normal TI-83+ this port is a shadow of [[83Plus:Ports:06|Port 06h]].

@@ Line 1: / Line 1: @@
-[[Category:83Plus:Ports:By Address|2E - CPU Speed Adjustment]] [[Category:83Plus:Ports:By Name|CPU Speed Adjustment]]
+[[Category:83Plus:Ports:By Address|2E - Memmory Access Delay]] [[Category:83Plus:Ports:By Name|Memmory Access Delay]]
 {{SE-Only Port|06}}
@@ Line 5: / Line 5: @@
 '''Port Number:''' 2Eh
-'''Function:''' CPU Speed Adjustment
+'''Function:''' Memmory Access Delay
-Bits 4 and 5 can adjust the CPU speed to a certain degree. In order for the speed adjustment to work bit 1 must be set in the appropriate LCD Delay port according to the contents of port 20. In other words, if you wish to adjust the speed at 6mhz you must set bit 1 of port 29. Other bits of this port 2E may affect the speed but nothing significant.  The default value for this port is 45h on the TI-84 Plus Silver Edition and 44h on the TI-83 Plus Silver Edition.
+This port will add a 1 cycle delay for certain types of reads for the ram or the flash. This port's affect is enabled by the lcd delay port currently selected by the current CPU speed.
 == Comments ==
 This port is not available on the normal TI-83+. On the normal TI-83+ this port is a shadow of [[83Plus:Ports:06|Port 06h]].
-== Example ==
- <nowiki>
-ld a,0
-out (20h),a    ;would be 6mhz
-in a,(29h)
-or 2           ;set bit 1
-out (29h),a
-ld a,74h       ;Set the CPU to ~5.1 MHz
-out (2Eh),a
-</nowiki>
 == Credits and Contributions ==
 * '''Michael Vincent:''' Documentation found [http://michaelv.org/programs/calcs/ports/port2e.html here].

@@ Line 7: / Line 7: @@
 '''Function:''' CPU Speed Adjustment
-Bits 4 and 5 can adjust the CPU speed to a certain degree. In order for the speed adjustment to work bit 1 must be set in the appropriate LCD Delay port according to the contents of port 20. In other words, if you wish to adjust the speed at 6mhz you must set bit 1 of port 29. Other bits of this port 2E may effect the speed but nothing significant.  The default value for this port is 45h on the TI-84 Plus Silver Edition and 44h on the TI-83 Plus Silver Edition.
+Bits 4 and 5 can adjust the CPU speed to a certain degree. In order for the speed adjustment to work bit 1 must be set in the appropriate LCD Delay port according to the contents of port 20. In other words, if you wish to adjust the speed at 6mhz you must set bit 1 of port 29. Other bits of this port 2E may affect the speed but nothing significant.  The default value for this port is 45h on the TI-84 Plus Silver Edition and 44h on the TI-83 Plus Silver Edition.
 === Read Values (bits 5-4)===

@@ Line 7: / Line 7: @@
 '''Function:''' CPU Speed Adjustment
-This port for reasons unknown has a slight effect on the CPU speed. It works in both the 6 MHz and 15 MHz modes. Every bit on the port affects the speed, but only bits 5 and 4 have any significant effects. The default value for this port is 45h on the TI-84 Plus Silver Edition and 44h on the TI-83 Plus Silver Edition.
+Bits 4 and 5 can adjust the CPU speed to a certain degree. In order for the speed adjustment to work bit 1 must be set in the appropriate LCD Delay port according to the contents of port 20. In other words, if you wish to adjust the speed at 6mhz you must set bit 1 of port 29. Other bits of this port 2E may effect the speed but nothing significant.  The default value for this port is 45h on the TI-84 Plus Silver Edition and 44h on the TI-83 Plus Silver Edition.
 === Read Values (bits 5-4)===
 * 00: The CPU is running at normal speed (100%)
-* 01: The CPU is running at ~82% of normal speed
+* 01: The CPU is running at ~90% of normal speed
-* 10: The CPU is running at ~99% of normal speed
+* 10: The CPU is running at ~95% of normal speed
-* 11: The CPU is running at ~81% of normal speed
+* 11: The CPU is running at ~86% of normal speed
-=== Write Values (bits 5 and 4)===
+=== Write Values (bits 5-4)===
 * 00: Set the CPU to run at 100% of normal speed
-* 01: Set the CPU to run at ~82% of normal speed
+* 01: Set the CPU to run at ~90% of normal speed
-* 10: Set the CPU to run at ~99% of normal speed
+* 10: Set the CPU to run at ~95% of normal speed
-* 11: Set the CPU to run at ~81% of normal speed
+* 11: Set the CPU to run at ~86% of normal speed
 == Comments ==
@@ Line 27: / Line 27: @@
 == Example ==
   <nowiki>
-ld a,74h   ;Set the CPU to ~12.09 MHz/~4.8 MHz
+ld a,0
 out (2Eh),a
 </nowiki>