C51: Maxim 390 Hangs on Math Operations

Information in this article applies to:

• C51 All Versions

QUESTION

The Maxim (formerly Dallas Semiconductors) 390 hangs when I try to use multiply, divide or shift operations. What's wrong?

ANSWER

You may have the On-Chip Arithmetic Accelerator enabled and are calling math functions from an interrupt routine. Math operations using the Maxim 390 math accelerator are not re-entrant.

MORE INFORMATION

• C51: Maxim 390 Math Accelerator Operations
• C51: Reentrancy Issues With the Dallas 390 Math Accelerator
• C51: Memory Types for Maxim 390 Contiguous Mode
• C51: Configuring Dallas 390 and 400 for Contiguous Mode

SEE ALSO

• MON390: CANNOT CONNECT TO DALLAS DS80C400 ON THE DS-TINI-1 B
• µVision DEBUGGER: Debugging With Maxim/Dallas DS5250 Monitor

Last Reviewed: Thursday, February 25, 2021