DSCOPE: ERROR 133 WHEN USING ASSIGN AND MON51

Information in this article applies to:

• C51 Version 5.50

SYMPTOMS

I am following the MCB520 Evaluation Board User's Guide (05.96) and on page 34 it states that in order to use Serial Port 1, the following assign command must be entered:

assign win <s1in >s1out

However when I enter this, I get Error 133: Undefined peripheral I/O function.

CAUSE

When you select MON51.DLL in dScope, all the virtual registers (VTREGS), such as s1in and s1out, are not relevent. This is because the program is running on hardware, not in a virtual simulation.

The MCB520 User's Guide is ambiguous on page 34. The assign command should be used if you are going to simulate your program in dScope, rather than run it on the MCB520 Evaluation Board.

RESOLUTION

You can send and receive serial data to your program running on the MCB520 board by loading a terminal program. dScope's Serial I/O window cannot be used.

Last Reviewed: Tuesday, June 08, 2004