83Plus:Ports:27 - Revision history

Dr. D'nar at 04:54, 14 March 2013

2013-03-14T04:54:39Z

2013-03-14T04:53:30Z

typo

2013-03-14T04:53:08Z

2013-03-14T04:51:11Z

I don't know who thought only values up to 12h were valid, but my actual crowd-sourced experiments say otherwise.

2013-03-12T16:28:58Z

‎Comments

2011-06-29T06:33:58Z

2005-08-23T14:08:28Z

Spell check

2005-08-19T02:55:22Z

minor reword .... previous edits were by me, it logged me out for some reason

2005-08-19T02:52:21Z

boxes running together

2005-08-19T02:51:59Z

reworded a bit, -{{wikify}}

@@ Line 20: / Line 20: @@
 This bares more than resemblance to port 28h so I guess they were meant to be used together.
-*255 = 16320, which is 64 bytes less than 65536. So you can't use this to completely override port 5. I don't why you would, but it tripped me up once while writing the experiments.
+*255 = 16320, which is 64 bytes less than 16384. So you can't use this to completely override port 5. I don't why you would, but it tripped me up once while writing the experiments.
 Port 27 and 28 appear to have no effect in memory mapping mode 1.

@@ Line 20: / Line 20: @@
 This bares more than resemblance to port 28h so I guess they were meant to be used together.
-*256 = 16320, which is 64 bytes less than 65536. So you can't use this to completely override port 5. I don't why you would, but it tripped me up once while writing the experiments.
+*255 = 16320, which is 64 bytes less than 65536. So you can't use this to completely override port 5. I don't why you would, but it tripped me up once while writing the experiments.
 Port 27 and 28 appear to have no effect in memory mapping mode 1.

@@ Line 14: / Line 14: @@
 === Write Values ===
-* [00h - 12h]: The value times 64 equals the number of bytes that get re-mapped starting from FFFFh. So a value of 12h would re-map data in FB80h - FFFFh.
+* [00h - FFh]: The value times 64 equals the number of bytes that get re-mapped starting from FFFFh. So a value of 12h would re-map data in FB80h - FFFFh.
 == Comments ==
 This bares more than resemblance to port 28h so I guess they were meant to be used together.
 Port 27 and 28 appear to have no effect in memory mapping mode 1.

@@ Line 15: / Line 15: @@
 === Write Values ===
 * [00h - 12h]: The value times 64 equals the number of bytes that get re-mapped starting from FFFFh. So a value of 12h would re-map data in FB80h - FFFFh.
 == Comments ==
-I have no clue why TI thinks it may be necessary to make 1180 bytes from ram page 0 at FB64h, but who knows it could be useful. This also bares more than resemblance to port 28h so I guess they were meant to be used together.
+This bares more than resemblance to port 28h so I guess they were meant to be used together.
-These port 27 and 28 appear to have no effect in memory mapping mode 1.
+Port 27 and 28 appear to have no effect in memory mapping mode 1.
 == Credits and Contributions ==

@@ Line 21: / Line 21: @@
 == Comments ==
 I have no clue why TI thinks it may be necessary to make 1180 bytes from ram page 0 at FB64h, but who knows it could be useful. This also bares more than resemblance to port 28h so I guess they were meant to be used together.
 == Credits and Contributions ==

@@ Line 8: / Line 8: @@
 '''Function:''' Block Memory Mapping C000h
-By an order of 64 bytes per block, this port can re-map data from ram page 0 to reflect the memory in C000h - FFFFh without regard of the contents of port 5. This port does not map the entire page, but only 64 bytes times the value in this port. It maps it starting from high memory (FFFFh) to low.
+By an order of 64 bytes per block, this port can re-map data from ram page 0 to reflect the memory C000h - FFFFh addresses without regard to the contents of port 5. This port does not map the entire page, but only 64 bytes times the value in this port. It maps it starting from high memory (FFFFh) to low.
 === Read Values ===

@@ Line 1: / Line 1: @@
 [[Category:83Plus:Ports:By Address|27 - Block Memory Mapping C000h]][[Category:83Plus:Ports:By Name|Block Memory Mapping C000h]]
 {{SE-Only Port|07}}
 == Synopsis ==
 '''Port Number:''' 27h