CCES doesn't recognize S registers

Instructions referencing the complementary registers throw an error. The syntax highlighting doesn't even show the Sx registers.

For example:

f0=f3*f4, f8=f8+f10, s3=dm(i2,m2);

The code is cut and paste form the programmers reference pg 6-17

Throws the error

 

[Error ea1227] ".Semantic Error in type 2 instruction.
Operands don't fit instruction template 'REG EQUAL REG PLUS_OP REG OR_OP REG EQUAL REG MINUS_OP REG SEMICOLON'.
Check for an out of range immediate value or illegal register.

Previous errors prevent assembly