Zilog EZ80F91AZA User Manual
Page 35
UM007518-1211
In-Depth Questions About Using RZK
Zilog Real-Time Kernel: eZ80
®
CPU
User Manual
25
Q:
How much overhead is consumed by the Priority Inheritance protocol?
A:
The Priority Inheritance protocol impacts the system only minimally. Typically, sys-
tem overhead involves changing a thread’s priority and scheduling.
Q:
Can I write an application to be run from Flash and debug it through ZDS II?
A:
Yes. You can write an application that runs from Flash. Observe the following proce-
dure to write the application:
1. Create a Flash-based project and add the application and required files to it.
2. Modify the settings as specified in this manual for Flash memory and generate a
.hex
file to be downloaded to Flash memory by using the Flash Loader integrated
within ZDS II.
3. Select
Projects
→
Settings
→
Linker
and define the
Category
as
Output
.
Select
IEEE 695
as the
executable format
and click
OK
. This setting is required
because the IEEE 695 format contains the debug information.
4. Build the application. Make sure that the
Chip Select
settings are mirrored as
described in this manual.
5. Connect to the target by selecting
Build
→
Debug
→
Connect To Target
.
6. Reset the eZ80 Development Platform by selecting
Build
→
Debug
→
Reset
.
Now you can debug your programs as usual.
Q:
How do I work with interrupts in RZK?
A:
Observe the following procedure for interrupt handling:
1. Install an interrupt handler for the appropriate interrupt using the
RZKInstall-
InterruptHandler()
routine and provide the interrupt handle and the interrupt
number.
2. Write a program such that the interrupt prolog first saves all registers and calls the
C ISR routine (if present) and then restores all registers in the order it is saved.
(You can accomplish this task by pushing the registers onto the stack and subse-
quently popping them from the stack in the order they were pushed.) For more
3. If RZK APIs are called in the C ISR routine then you are required to call
RZKISR-
Prolog()
and
RZKISREpilog()
functions before and after the ISR routine
respectively.