[Openec] pdata access

[Paul Fox]

frieder wrote:
 > Hi Paul,
 > 
 > I've just seen that pdata access was enabled
 > and "P2 = 0xf4;" was set in
 > unsigned char early_startup(void)
 > 
 > For SDCC this is likely not needed
 > (see section 4.1.1 "pdata access by SFR" and
 > _XPAGE .)

yes, i saw that, and in the lib startup source.

 > 
 > For Keil you should maybe recheck that within
 > startup.a51 the "PDATASTART EQU" is set
 > appropriately. (setting it in early_startup()
 > might be too early/too late/overwritten
 > causing initialized pdata variables to have
 > unexpected values)

we're not using their complete startup suite -- perhaps
it would have it we were, but pdata access didn't work in
the previous incarnation of our EC code, nor in the current
version, until i added that P2 assignment.

 > 
 > I assume you use pdata with SDCC successfully?

yes.

paul
=---------------------
 paul fox, pgf at laptop.org