From 94ef5555fee165faf63925641e3ac5300e528b99 Mon Sep 17 00:00:00 2001 From: Jose Antonio Ortega Ruiz Date: Thu, 5 Jun 2003 22:23:10 +0000 Subject: (Shift operators): SLC and SRC act on AX, not on A. (Conversion operators): correct description of digit representation. --- doc/mdk_tut.texi | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) (limited to 'doc') diff --git a/doc/mdk_tut.texi b/doc/mdk_tut.texi index 42111fc..a33444a 100644 --- a/doc/mdk_tut.texi +++ b/doc/mdk_tut.texi @@ -4,7 +4,7 @@ @c Free Software Foundation, Inc. @c See the file mdk.texi for copying conditions. -@c $Id: mdk_tut.texi,v 1.8 2003/06/02 23:19:52 jao Exp $ +@c $Id: mdk_tut.texi,v 1.9 2003/06/05 22:23:10 jao Exp $ @node MIX and MIXAL tutorial, Getting started, Installing MDK, Top @comment node-name, next, previous, up @@ -721,7 +721,21 @@ Digits are represented in MIX by the range of values 30-39 (digits @noindent the represented number is 0012315904, and @samp{NUM} will store this value in @samp{rA} (i.e., we end up with @samp{[rA]} = @w{+ 0 46 62 52 -0} = 12315904. @samp{CHAR} performs the inverse operation. +0} = 12315904). + +If any byte in @samp{rA} or @samp{rB} does not belong to the range +30-39, it is taken by @samp{NUM} as the representation of the digit +obtained by taking its value modulo 10. E.g. 30, 40, 50, 60 all represent +the digit 0; 2, 12, 22,... the digit 2, and so on. For instance, the +number 0012315904 mentioned above could also be represented as + +@example +[rA] = + 10 40 31 52 23 +[rX] = + 11 35 49 20 54 +@end example + +@samp{CHAR} performs the inverse operation, using only the values 30 +to 39 for representing digits 0-9. @node Shift operators, Miscellaneous operators, Conversion operators, MIX instruction set @comment node-name, next, previous, up @@ -750,19 +764,21 @@ the instructions on the left column: @multitable {SLA 00} {[rA] = - 00 00 00 00 00} @item SLA 2 @tab [rA] = - 03 04 05 00 00 +@item SLA 6 @tab [rA] = - 00 00 00 00 00 @item SRA 1 @tab [rA] = - 00 01 02 03 04 -@item SLC 3 @tab [rA] = - 04 05 01 02 03 -@item SRC 24 @tab [rA] = - 05 01 02 03 04 @end multitable @noindent -Note that the sign is unaffected by shift operations. On the other hand, -@samp{SLAX} and @samp{SRAX} treat @samp{rA} and @samp{rX} as a single -10-bytes register (ignoring again the signs), so that, if we begin with -@samp{[rA]} = @w{+ 01 02 03 04 05} and @samp{[rX]} = @w{- 06 07 08 09 -10}, executing @samp{SLAX 3} would yield: - -@example -[rA] = + 04 05 06 07 08 [rX] = - 09 10 00 00 00 +Note that the sign is unaffected by shift operations. On the other +hand, @samp{SLC}, @samp{SRC}, @samp{SLAX} and @samp{SRAX} treat +@samp{rA} and @samp{rX} as a single 10-bytes register (ignoring again +the signs). For instance, if we begin with @samp{[rA]} = @w{+ 01 02 03 +04 05} and @samp{[rX]} = @w{- 06 07 08 09 10}, we would have: + +@multitable {SLC 00} {[rA] = - 00 00 00 00 00} {[rA] = - 00 00 00 00 00} +@item SLC 3 @tab [rA] = + 04 05 06 07 08 @tab [rX] = - 09 10 01 02 03 +@item SLAX 3 @tab [rA] = + 04 05 06 07 08 @tab [rX] = - 09 10 00 00 00 +@item SRC 4 @tab [rA] = + 07 08 09 10 01 @tab [rX] = - 02 03 04 05 06 +@item SRAX 4 @tab [rA] = + 00 00 00 00 01 @tab [rX] = - 02 03 04 05 06 @end example @node Miscellaneous operators, Execution times, Shift operators, MIX instruction set -- cgit v1.2.3