Arithmetic on the D register

[savage]

Hello Forum,

Could anyone suggest please, why I get an error message with the following..

@p
D=M
D=D-8191

Thanks

John Savage

[cadet1620]

savage wrote

Hello Forum,

Could anyone suggest please, why I get an error message with the following..

@p
D=M
D=D-8191

Thanks

John Savage

Reread 4.2.3 and note figure 4.3.  D=D-8191 is not one of the C-instructions. Study the example code in figure 4.2.

--Mark

[savage]

Thanks again Mark,
Now I understand. The @ together with the C instructions makes for a powerful combination.

Cheers

John Savage