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+====== Short 8bit * 8bit = 16bit multiply ======
+A small multiplication routine using the ancient egyptian multiplication algorithm. Factors should be stored in the FAC1 and FAC2 variables, the product can be found in Akku (high byte) and the X-Register (low byte). FAC1 will be destroyed. No tables required.
+<code>
+FAC1     = $58
+FAC2     = $59
+        ; A*256 + X = FAC1 * FAC2
+MUL8
+        lda #$00
+        ldx #$08
+        clc
+m0      bcc m1
+        clc
+        adc FAC2
+m1      ror
+        ror FAC1
+        dex
+        bpl m0
+        ldx FAC1
+        rts
+</code>