From: Luke Kenneth Casson Leighton Date: Sun, 9 Feb 2020 18:24:35 +0000 (+0000) Subject: add docstring explaining partitioned-add X-Git-Tag: ls180-24jan2020~218 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8c4baccb7201d450840015f27f05ff53095e6c82;p=ieee754fpu.git add docstring explaining partitioned-add --- diff --git a/src/ieee754/part_mul_add/adder.py b/src/ieee754/part_mul_add/adder.py index c6409a7e..c2e75257 100644 --- a/src/ieee754/part_mul_add/adder.py +++ b/src/ieee754/part_mul_add/adder.py @@ -127,6 +127,18 @@ class PartitionedAdder(Elaboratable): exp-o : ....xN...xN...xN...xN... (32+4 bits - x to be discarded) o : .... N... N... N... N... (32 bits - x ignored, N is carry-over) + partition: p p p p (4 bits) + carry-in : c c c c (4 bits) + C = c & P: C C C c (4 bits) + I = P=>c : I I I I (4 bits) + a : AAAA AAAA AAAA AAAA AAAA (32 bits) + b : BBBB BBBB BBBB BBBB BBBB (32 bits) + exp-a : 0AAAApAAAACAAAACAAAACAAAAc (32+4 bits, P=1 if no partition) + exp-b : 0BBBB0BBBBIBBBBIBBBBIBBBBI (32 bits plus 4 zeros) + exp-o : o....oN...oN...oN...oN...x (32+4 bits - x to be discarded) + o : .... N... N... N... N... (32 bits - x ignored, N is carry-over) + carry-out: o o o o (4 bits) + :attribute width: the bit width of the input and output. Read-only. :attribute a: the first input to the adder :attribute b: the second input to the adder