Sundance SMT365 - Manual (Page 16)

Version 2.3 Page 16 of 28 SMT365 User Manual
CONFIG & NMI
The TIM specification describes the operation of an open-collector type signal
CONFIG that is driven low after reset.
This signal, on a standard C4x based TIM, is connected to the processor’s IIOF3 pin.
On the SMT365, the CONFIG signal is asserted after power on, and can be released
by writing the value (1<<6) to the config register. Conversely, CONFIG may be re-
asserted by writing 0 to this bit. It is not possible for software to read the state of the
CONFIG signal.
The NMI signal from the TIM connector can be routed to the DSP NMI pin.
WARNING: Several software components include code sequences that assume
setting GIE=0 in the DSP CSR will inhibit all interrupts; NMI violates that assumption.
If an NMI occurs during such code sequences it may not be safe to return from the
interrupt. This may be particularly significant if you are using the compiler’s software
pipelining facility.
Config Register
31–8 7 6 5–0
NMI CONFIG
Field Description
0 drive CONFIG low
CONFIG
1 tri-state CONFIG
0 Disconnect NMI from the DSP
NMI
1 Connect NMI from TIM to the DSP.
Config and NMI DSP lines are described in the SMT6400 help file .