Interrupt
Description
As shown in Figure 101, the MMC controller implements eight interrupt sources reported
in MCBI, EORI, EOCI, EOFI, F2FI, F1FI, and F2EI flags in MMCINT register. These
flags are detailed in the previous sections.
All these sources are maskable separately using MCBM, EORM, EOCM, EOFM, F2FM,
F1FM, and F2EM mask bits respectively in MMMSK register.
The interrupt request is generated each time an unmasked flag is set, and the global
MMC controller interrupt enable bit is set (EMMC in IEN1 register).
Reading the MMINT register automatically clears the interrupt flags (acknowledgment).
This implies that register content must be saved and tested interrupt flag by interrupt
flag to be sure not to forget any interrupts.
Figure 101. MMC Controller Interrupt System
MCBI
MMINT.7
MCBM
MMMSK.7
EORI
MMINT.6
EORM
MMMSK.6
EOCI
MMINT.5
EOCM
MMMSK.5
EOFI
MMINT.4
MMC Interface
Interrupt Request
EOFM
MMMSK.4
F2FI
MMINT.3
EMMC
IEN1.0
F2FM
MMMSK.3
F1FI
MMINT.2
F1FM
MMMSK.2
F2EI
MMINT.1
F2EM
MMMSK.1
F1EI
MMINT.0
F1EM
MMMSK.0
150
AT8xC51SND2C
4341D–MP3–04/05
ATMEL [ ATMEL ]
