Using the TWR-MEM board with TWRK60N512

[ERussell]

I would like to use MRAM memory of the TWR-MEM board with the TWRK60N512 kit to be able to debug larger programs in RAM. I am using CW10.1, MQX, and PE.

What I would like to know is how to setup the MRAM for use in my program. It is not clear to me how to specify the additional RAM. Modifying the lcf file doesn't work because it gets overwritten and fields in the PE CPU component for external memory are unavailable. Looking in init_hw.c, it appears that the MRAM is not even initialized if PE_LDD_VERSION is defined. 

Also is it necessary to remove R14 for the MRAM to work?

Thanks.

[DavidS · Accepted solution]

Hi,

I was able to get the TWR-K60N512 kit with TWR-MEM Rev B working.

Please reference another thread:

https://community.freescale.com/message/301229

Regards,

David

[ProcessorExpert]

Hello,

External memory in Processor Expert can be configure in the CPU component, you just need to enable "External bus" property, configure the "Chip select" first and then add and configure "external memory" property and block(s) under it.

Placement of data and code can inside LCF file can be configured in the Build options tab.

However, I see a possible issues with debugging from this memory as the debugger probably won't be able to upload to external memory by default.

We will prepare some simple example showing the usage of the TWR-MEM with Processor Expert and post it here.

best regards
Petr Hradsky
Processor Expert Support Team

[ERussell]

I'm very concerned about not being able to use external memory for debugging. Is this a limitation of CW's debugger or other debuggers as well? My code is much larger than the available internal RAM and would probably just fit into the Flash but debugging in Flash is not as efficient as in RAM.

Thanks.

[ERussell]

I have tried configuring external memory using PE but haven't been able to. The "external bus" property in the CPU component is set at disabled and cannot be enabled. Clicking on the setting doesn't bring up a popup menu for a choice to enable or allow any editing. Is there some other setting that could be preventing the editing of this property?

[ProcessorExpert]

You should be able to change "External memory" property to |Enabled" using the drop-down menu.

Just click on the "Disabled" once" to select it and then click again on the down arrow on the right site and select "Enabled" value.

[ERussell]

When I click on the external bus property I get the message:

This value is required by the componentMQX1:MQX because of the following reason: Don't initialize this peripheral. It is initialized by MQX.

How can I enable the external bus from MQX?

[ProcessorExpert]

I'm sorry Sorry, I haven't realized MQX is initializing external bus itself so Processor Expert dosn't allow to initialize it using Processor Expert.

This question regards MQX, so I''ll move your question to MQX section of forum.

best regards
Petr Hradsky
Processor Expert Support Team