Lucent Technologies DSP1611, Information Manual

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DSP1611/17/18/27/28/29 DIGITAL SIGNAL PROCESSOR Information Manual
Instruction Set Summary April 1998
B-13
DRAFT COPY
Lucent Technologies Inc.
R = Y
(load register from Y-space memory)
perform (R)
←
(*rM); then
modify rM
The contents of register R are replaced with the current contents of the Y-space memory location pointed to by rM
where rM is specified by the two most significant bits of the Y field:
00 - r0 01- r1 10 - r2 11 - r3
The value of rM is then postmodified where the postmodification is specified by the two least significant bits of the
Y field.
Register R is one of the general sets of registers listed under the long immediate load.
Note: Writing the psw also writes the a0 and a1 guard bits.
Notes:
1. If y, yl, or x are the destination registers (R), the assembler assembles this instruction as a single-cycle multiply/
ALU instruction. If a two-cycle move encoding is necessary, the optional mnemonic move may be used. For
example:
move y = *r1 forces a move encoding
2. R = pop(*rM) is a different assembly-language form for two statements:
*rM– – followed by R = *rM and is used for stack operations. The pointer register rM is decremented, and data
is written from the new memory location to the register R. The decrement instruction is not interruptible.
2 LSBs of Y Action Symbol
00 no action *rM
01 postincrement *rM++
10 postdecrement *rM– –
11
†
† Code 11, in this case, means add the current value of the j regis-
ter to rM after accessing *rM.
postincrement by (j) *rM++j
Bit
15 14 13 12 11 10 9—4 3—0
Field 0 1 1 1 1 0 R Y
Words: 1
Cycles: 2
Group: Data Move
Addressing: Register, Register Indirect
Flags affected: None
Interruptible: Yes
Cacheable: Yes
Format: 7