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Resizing the Matrix

05/31/2009

Today I did two things: to read about mainframes and to play with different sizes for my Trans Matrix using a little utility that I improvised yesterday.

My readings were as in a tale of castles and prices. Now I realize why I don't like PCs: the real action is into mainframe engineering... but anyways, this is not about my professional frustrations.

As per the Matrix, it is almost decided that my computer will address words (16 bits), not bytes. Here are the results for different Matrix configurations:

-------------- CONFIGURATION # 1 -------------------------------------------
Max Memory                  : 32 MB          
Page Frame size             : 1 Kw (2KB)
Max simultaneous processes  : 16

LINEAR ADDRESS:  Width: 24  =>  Page field  : 14   Offset field     : 10
MATRIX ENTRY  :  Width: 20  =>  Control bits: 6    Physical Addr fld: 14

Matrix Size: 256K X 20 = 640 KB

-------------- CONFIGURATION # 2 -------------------------------------------
Max Memory                  : 8 MB          
Page Frame size             : 1 Kw (2KB)
Max simultaneous processes  : 16

LINEAR ADDRESS:  Width: 22  =>  Page field  :  12    Offset field   : 10
MATRIX ENTRY  :  Width: 16  =>  Control bits:  4   Physical Addr fld: 12

Matrix Size: 64K x 16 = 128 KB

-------------- CONFIGURATION # 3 -------------------------------------------
Max Memory                  : 4 MB          
Page Frame size             : 1 Kw (2KB)
Max simultaneous processes  : 16

LINEAR ADDRESS:  Width: 21  =>  Page field  : 11     Offset field   : 10
MATRIX ENTRY  :  Width: 16  =>  Control bits: 5    Physical Addr fld: 11

Matrix Size: 32K X 16 = 64 KB

-------------- CONFIGURATION # 4 -------------------------------------------
Max Memory                  : 2 MB          
Page Frame size             : 1 Kw (2KB)
Max simultaneous processes  : 16

LINEAR ADDRESS:  Width: 20  =>  Page field  : 10     Offset field   : 10
MATRIX ENTRY  :  Width: 16  =>  Control bits: 6    Physical Addr fld: 10

Matrix Size: 16K X 16 = 32 KB
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This last seems close enough to reality.