INTERNAL SPECIFICATIONS

4.6.2.6 SERR

SERR is the status flag set when a framing error or overrun error is generated during UART mode (mode 1, 2, or 3).

Framing error:

The SERR flag is set when no stop bit is detected in UART mode. Framing error is detected irrespective of the data reception conditions set by SM2.

Overrun error:

The SERR flag is also set when the next data is ready to be transferred from the input shift register to the SBUF which is already full in UART mode. Note that an overrun error is only detected when the data reception conditions set by SM2 have been satisfied. Although the SERR flag is set by hardware when a framing or overrun error is generated, it is not an interrupt request flag. The flag must be checked by software to determine whether it has been set or not. The flag must also be cleared by software. Since the SERR flag is set by the logical OR of framing and overrun errors, it is not possible to determine whether the error is a framing or overrun error simply by checking the flag.

SERR is located at bit 5 of IOCON (I/O control register) specified by data address 0F8H. This bit can also be specified by bit address 0FDH.

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Sonic Alert msm80154s, msm83c154s, msm85c154hvs user manual Serr