z16f2811 ZiLOG Semiconductor, z16f2811 Datasheet - Page 316

• Manufacturer Part Number: z16f2811
• Description: High Performance Microcontrollers
• Manufacturer: ZiLOG Semiconductor

PS022006-0207
Debug Lock
Error Reset
Internal
System Reset
Debug Reset
Debug Pin
Reset Pin
The interface has a locking mechanism to prevent user code from disabling the OCD and
using the DBG pin as a UART or GPIO pin. The
prevents you from disabling the OCD and modifying any register that would inhibit
communication with the OCD. The default state of the
the
In order to use the DBG pin as a UART or GPIO pin, you must program the
option bit to zero so the
register is unlocked, software then clears the
UART or GPIO pin.
If the
locked before code has the chance to disable the OCD. This is done by initializing the
Debugger during reset and writing the
The serial interface has an Auto-Reset mechanism that resets the serial interface when a
Transmit Collision or Receive Framing Error is detected. When a Transmit Collision or
Receive Framing Error is detected when
currently in progress, transmits a Serial Break condition for 4096 system clocks, and sets
the
the error.
DBGUART
ABSRCH
DBGUART
bit in the DBGCTL register. This break is sent to ensure the host also detects
option bit.
Reset Timeout
option bit is cleared and the
Figure 68. Initialization during Reset
OCDLOCK
P R E L I M I N A R Y
control bit is cleared after reset. After the control
OCDLOCK
OCDEN
80H
Reset Pin Remains Asserted
OCDLOCK
OCDEN
is set, the OCD aborts any command
control bit to 1.
DBGLOCK
00H
control bit to use the DBG pin as a
control bit is not set, the
DBGLOCK
IDH
bit in the DBGCTL register
Product Specification
IDL
bit is set accordingly to
ZNEO
On-Chip Debugger
™
Z16F Series
DBGUART
OCD
is still
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