LBYT

From NDWiki
Revision as of 16:06, 24 July 2010 by TArntsen (talk | contribs) (LBYT instruction)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
LBYT
Description Load byte
Format LBYT
Code 142 2008
Affected A
Type User
Architecture ND-100, ND-110

LBYT is an assembly instruction. A byte specified by the T and X registers is loaded into the A register bits 0-7, with the A register bits 8-15 cleared.

As the ND-1x0's RAM is addressed by 16-bit words two registers are needed to address bytes. The T register points to a word, and the X register indicates the byte offset, counting from the left byte of the word pointed to by T.

Word address = (T) + (X)/2
If X is even (bit 0 = 0), the byte is in bits 8-15 of the word
If X is odd (bit 0 = 1), the byte is in bits 0-7 of the word

References