EUControlSpec.tioga
by Mark Ross January 20, 1987 8:09:18 am PST
Last Edited by: Ross May 28, 1987 10:26:19 am PDT
EUControl Specification:
EUControl[0:2] =>
000 NOP
001 Adder
010 Logical Unit
011 Shifter
100 Priority Encoder
101 Tag Unit
110 Load Multiplier
111 Unload Multiplier
EUControl[3:6] is defined differently depending upon the selected unit. A breakdown by
functional unit is shown below:
Adder:
EUControl[3:6] =>
0xx0 add no carry (d1+d2)
0xx1 add with carry (d1+d2+1)
1xx0 sub no carry (~d1+d2)
1xx1 sub with carry (~d1+d2+1)
Logical Unit:
EUControl[3:6] =>
0001 AND
0110 XOR
0111 OR
1000 NOR (no opcode)
1110 NAND (no opcode)
Shifter:
EUControl[3:6] =>
xxxx
Priority Encoder:
EUControl[3:6] =>
xxxx
Load Multiplier:
EUControl[3:6] =>
x00x Load signed 32 bit number
x01x Load unsigned 32 bit number
x1?x Load Floating Point number
? should be set to 0 or 1 depending on whether or not mantissa is padded by a 0.
Use 0 if it is not padded and 1 if it is padded.
Unload Multiplier:
EUControl[3:6] =>
xxxx unloads the result.