Confusion re Tiny 15 and osccal

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I'm a beginner at this and I'm switching from tiny 11 to tiny 15. The 11 runs at 1mhz using the int RC osc.The 15 runs at 1.6M so I have to adjust some timing delays to achieve delays of 13 u secs or so.
From all I've read, It seems that the factory cal. byte can't be read by the application program. My programmer, a micromaster LV won't transfer the value to flash automatically. It seems I have to dothis manually for each chip- read the Tiny, get the cal byte, copy it to flash at 3ff. Then a piece of code on power up reads the value from 3ff and dumps it in OSCCAL ($31). Why can't the application program access where the cal byte is, just like in a PIC? Sadly ( wash my mouth out with soap and water) this is about the only point a pic scores over the Tinys. Or am I missing something? I've got lots of these to do and it's going to be a real pain by the looks of it.
Is there really no way to automate this?

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The problem is that the OSCCAL value resides in the signature address space. This area of memory is not accessable in user mode. It can only be accessed when the processor is in programming mode.

You can automate the process by writting your own programming/calibration routines and running them from another Atmel uP. Here are some links to information that you will need to build your own programmer (or you could just use an STK500). But you will have to program and calibrate one board at a time.

http://www.atmel.com/dyn/resourc...
http://www.atmel.com/dyn/resourc...

Also, you may be able to use the software archive "ISPR3-30.exe" on the Atmel website to get the ISP code and mofify it to suit your needs.