When it is enabled, issuing a RTIO event replaces any existing RTIO event with the same timestamp. This makes sense in a limited number of cases, e.g. TTL outputs, where you can override the level previously set by the kernel (e.g. in ttl.off(); ttl.on()
, ttl.off()
is a no-op).
When it is disabled, you get a RTIO collision error instead.