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Description Store byte
Format SBYT
Code 142 6008
Affected (ea)
Type User
Architecture ND-100, ND-110

SBYT is an assembly instruction. The byte in the A register bits 0-7 is stored in one half of the effective address defined by the T and X registers. The other half of the location is unaffected.

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 stored in bits 8-15 of the word
If X is odd (bit 0 = 1), the byte is stored in bits 0-7 of the word