z8f083a ZiLOG Semiconductor, z8f083a Datasheet - Page 154

• Manufacturer Part Number: z8f083a
• Description: High-performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

On-Chip Debugger Control Register Definitions
PS026308-1207
OCD Control Register
•
•
•
The OCD control register controls the state of the On-Chip Debugger. This register is used
to enter or exit DEBUG mode and to enable the
Z8 Encore! F083A Series device.
A reset and stop function is achieved by writing
function is achieved by writing
function is implemented by writing
program memory size and is approximately equal to the system clock period multiplied by
the number of bytes in the program memory.
DBG
DBG
DBG
Step Instruction (10H)—The step instruction command, steps one assembly instruction
at the current program counter (PC) location. If the device is not in DEBUG mode or the
Flash read protect option bit is enabled, the OCD ignores this command.
DBG
Stuff Instruction (11H)—The stuff instruction command, steps one assembly instruction
and allows specification of the first byte of the instruction. The remaining 0-4 bytes of the
instruction are read from program memory. This command is useful for stepping over
instructions where the first byte of the instruction has been overwritten by a breakpoint. If
the device is not in DEBUG mode or the Flash read protect option bit is enabled, the OCD
ignores this command.
DBG
DBG
Execute Instruction (12H)—The execute instruction command allows sending an entire
instruction to be executed to the eZ8 CPU. This command also steps over breakpoints. The
number of bytes to send for the instruction depends on the Opcode. If the device is not in
DEBUG mode or the Flash read protect option bit is enabled, this command reads and
discards one byte.
DBG
DBG
←
→
→
←
←
←
←
←
0EH
CRC[15:8]
CRC[7:0]
10H
11H
opcode[7:0]
12H
1-5 byte opcode
41H
to this register. If the device is in DEBUG mode, a run
40H
to this register.
BRK
81H
instruction. It also resets the
to this register. A reset and
Z8 Encore!
Product Specification
®
On-Chip Debugger
F083A Series
G
o
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