Hints & Tips

DM41X PPC ROM

Various useful functions from the PPC ROM

Solve (SV)

Similar to other Solvers (e.g. the Advantage Pac Solve) but with some minor differences to be aware of.

  • Put the Global Label (name) of the program (in this example it's LBL AA) containing the expression to be solved in register 6
    • ALPHAAAALPHA
    • XEQALPHAASTOALPHA06
  • The program with the expression to be solved must be written as though unknown x is on the x-stack only
    • other solvers “fill the stack” with x
    • here you need to manipulate the stack to get x as needed. It's easiest is to just ENTER ENTER ENTER and then treat the stack the same as other solvers (i.e. as if it's filled with x and you use x<>y to pull a fresh copy of x as needed in the expression).
  • Put a “step size” in y and a “start value” in x (e.g. -3)
    • 0 ENTER -3
  • run SV

example

2x2 + 3x - 4 = 0

Prog “AA”

LBL AA
ENTER
ENTER
ENTER
x^2
2
*
x<>y
3
*
+
4
-
RTN

for the first root

  • 0 ENTER 1
  • XEQALPHA SV ALPHA

and the answer comes…..

0.850781059

for the second root

  • 0 ENTER -3
  • XEQALPHA SV ALPHA

and the answer comes…..

-2.350781060

Integrate (IG)

This is very similar to SV - the main difference is that the Global Label for the program containing the expression to be integrated is stored with ASTO in Register 10. I'm using AA as a general scratchpad Program label for use with Solve and Integrate…

  • ALPHAAAALPHA
  • XEQALPHAASTOALPHA10

For SV it's R06.

Otherwise carry out the same procedure for storing the expression.

Time taken for integration, and the accuracy obtained, is set by the display format - the more digits the longer the integration takes.

Set SCI 04 for most cases.

  • Set the name of the prog. in Reg 10
  • Edit the prog. for the expression to be integrated
  • Set the display format/accuracy to SCI 04
  • The limits of integration are set
    • lowerENTER upper
  • Then the IG routine is executed
    • XEQALPHAIGALPHA

John Pumford-Green 24/01/26 10:29 GMT

Further Information


Navigation