Echelon Neuron - Manual (Page 134)

SHRA (Shift Right Arithmetically)
The SHRA instruction shifts the byte in TOS one bit to the right arithmetically.
The SHRA instruction uses the implicit addressing mode. This instruction
moves bit 0 of TOS into the Carry flag, and leaves bit 7 of TOS unchanged.
Figure 14 shows the operation of the SHRA instruction.
TOS
7 0
C
6
Figure 14. The SHRA Instruction
The SHRA instruction applies to Series 3100, 5000, and 6000 devices.
Syntax:
The SHRA instruction requires no operands:
SHRA
Table 55 describes the attributes of the SHRA instruction.
Table 55. SHRA Instruction
Instruction Hexadecimal
Opcode
Instruction
Size (Bytes)
CPU Cycles
Required
Affect on
Carry Flag
SHRA 3C 1 2 Modified
Example:
The following example pushes the number 150 (h’96) onto the data stack, and
then uses the SHRA instruction to shift the TOS value right arithmetically.
After the SHRA instruction completes, TOS has the value 203 (h’CB) and the
Carry flag is set to 0 (the previous value of bit 0 in TOS).
push #d’150 ; ( d’150, -- )
shra ; ( d’203, -- )
124 Neuron Assembly Language Instruction Statements