Rn = Fdep Rx By Ry|<Bit6>:<Len6> - Analog Devices ADSP-2106x SHARC User Manual

Shifter
B Compute Operations
Rn = FDEP Rx BY Ry|<bit6>:<len6>
Syntax:
Rn = FDEP Rx BY Ry
Rn = FDEP Rx BY <bit6>:<len6>
Function:
Deposits a field from register Rx to register Rn. The input field is right-aligned
within the fixed-point field of Rx. Its length is determined by the len6 field in
register Ry or by the immediate len6 field in the instruction. The field is
deposited in the fixed-point field of Rn, starting from a bit position determined
by the bit6 field in register Ry or by the immediate bit6 field in the instruction.
Bits to the left and to the right of the deposited field are set to 0. The floating-pt.
extension field of Rn (bits 7-0 of the 40-bit word) is set to all 0s. Bit6 and len6 can
take values between 0 and 63 inclusive, allowing for deposit of fields ranging in
length from 0 to 32 bits, and to bit positions ranging from 0 to off-scale left.
39
Ry
39
Rx
len6 = number of bits to take from Rx, starting from LSB of 32-bit field
39
Rn
bit6 = starting bit position for deposit,
referenced from LSB of 32-bit field
Example: If len6=14 and bit6=13, then the 14 bits of Rx are deposited in Rn bits
34-21 (of the 40-bit word).
39 31
|--------|--------|--abcdef|ghijklmn|--------|
39 31
|00000abc|defghijk|lmn00000|00000000| 00000000 |
\--------------/
Status flags:
SZ Is set if the output operand is 0, otherwise cleared
SV Is set if any bits are deposited to the left of the 32-bit fixed-point output
field (i.e., if len6 + bit6 > 32), otherwise cleared
B – 64
SS Is cleared
www.BDTIC.com/ADI
19
len6
deposit field
bit6
23 15 7
\-------------/
14 bits
23 15 7
|
bit position 13 (from reference point)
13 7 0
bit6
7 0
7 0
reference point
0
Rx
0
Rn