Z8F0113HJ005EG Datasheet, PDF (177/245 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F0823 Series
Product Specification
162
On-Chip Debugger Commands
The host communicates to the OCD by sending OCD commands using the DBG interface.
During normal operation, only a subset of the OCD commands are available. In DEBUG
Mode, all OCD commands become available unless the user code and control registers are
protected by programming the Flash Read Protect Option bit (FRP). The Flash Read Pro-
tect Option bit prevents the code in memory from being read out of Z8 Encore! XP F0823
Series products. When this option is enabled, several of the OCD commands are disabled.
Table 101 is a summary of the OCD commands. Each OCD command is described in fur-
ther detail in the pages that follow this table. Table 102 on page 167 also indicates those
commands that operate when the device is not in DEBUG Mode (normal operation) and
those commands that are disabled by programming the Flash Read Protect Option bit.
Table 101. OCD Commands
Debug Command
Read OCD Revision
Reserved
Read OCD Status Register
Read Runtime Counter
Write OCD Control Register
Read OCD Control Register
Write Program Counter
Read Program Counter
Write Register
Command
Byte
00H
01H
02H
03H
04H
05H
06H
07H
08H
Read Register
Write Program Memory
Read Program Memory
Write Data Memory
Read Data Memory
Read Program Memory CRC
Reserved
Step Instruction
Stuff Instruction
Execute Instruction
Reserved
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
12H
13H–FFH
Enabled when not Disabled by Flash Read Protect
in DEBUG Mode? Option Bit
Yes
–
–
–
Yes
–
–
–
Yes
Cannot clear DBGMODE bit.
Yes
–
–
Disabled.
–
Disabled.
–
Only writes of the Flash Memory Con-
trol registers are allowed. Additionally,
only the Mass Erase command is
allowed to be written to the Flash Con-
trol Register.
–
Disabled.
–
Disabled.
–
Disabled.
–
Yes.
–
–
–
–
–
–
–
Disabled.
–
Disabled.
–
Disabled.
–
–
PS024315-1011
PRELIMINARY
On-Chip Debugger Commands