Using 2kbyte RAM nec microcontroller (78F0058 78F0078)

[psubiaco]

78f0078

Hello.
I've not understood how to use the internal expansion RAM of 78F0078 nec microcontroller.
Infact the micrcontroller user manual don't specify the way to address the 1024 bytes located between F400 and F7FF.
Please could you help me? Need to know which kind of variables should be allocated there, and how to tell IAR compiler that.
Thank you in advance. Paolo

 

[psubiaco]

78f0058

From NEC electronics Europe, they answer me that: [hr:f84063b571]


To define a variable located in the expansion memory you have to

1) define a new segment in this area in the xcl-file or use the default
segment IXRAM
2) use the #pragma memory statement before the variable definition:

#pragma memory=dataseg(IXRAM)
unsigned char v1;
unsigned char v2;
unsigned int v3;
...
#pragma memory = default

Now all variables defined after the #pragma memory=dataseg(IXRAM)
statement are located in the
IXRAM segment until the statement #pragma memory = default.
Please keep in mind that variables located in the segment IXRAM (and also
in other user-defined segments)
are not initialized by the default-cstartup-module. For details please have
look at the compiler manual at page 188.

[hr:f84063b571]
I've not specify who has kindly answer me for privacy reasons.
Bye. Paolo