data loss may result during debugging. This peripheral can be forced to halt operation during debugging -
refer to the Debug Control (DBGCTRL) register for details.
29.5.8. Register Access Protection
All registers with write-access can be optionally write-protected by the Peripheral Access Controller
(PAC).
Note:
Optional write-protection is indicated by the "PAC Write-Protection" property in the register
description.
When the CPU is halted in debug mode, all write-protection is automatically disabled. Write-protection
does not apply for accesses through an external debugger.
Related Links
PAC - Peripheral Access Controller
on page 50
29.5.9. Analog Connections
Analog functions are connected directly between the analog blocks and the I/O pads using analog buses.
However, selecting an analog peripheral function for a given pin will disable the corresponding digital
features of the pad.
29.5.10. CPU Local Bus
The CPU local bus (IOBUS) is an interface that connects the CPU directly to the PORT. It is a single-
cycle bus interface, which does not support wait states. It supports 8-bit, 16-bit and 32-bit sizes.
This bus is generally used for low latency operation. The Data Direction (DIR) and Data Output Value
(OUT) registers can be read, written, set, cleared or be toggled using this bus, and the Data Input Value
(IN) registers can be read.
Since the IOBUS cannot wait for IN register resynchronization, the Control register (CTRL) must be
configured to continuous sampling of all pins that need to be read via the IOBUS in order to prevent stale
data from being read.
Atmel SAM L22G / L22J / L22N [DATASHEET]
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