Can I boot & program the EEPROM from a PC without the xtal?
godzich
Posts: 74
Hi,
Please pardon me (the prop is still fairly new for me), if I'm asking something obvious. I fully understand that the prop has an built in oscillator that can be used instead of an external XTAL, but with fairly high tolerances in clock frequency.
I plan to use the prop with the internal oscillator in an UART application in such a manner, that the prop measures the length of a received break signal at the uart Rx terminal. The prop measures the length of the break and adjusts its receiver clock accordingly. I know how to program this.
My question is:
Can the propeller and the accompanying external program EEPROM be serially booted and/or programmed - without a precise external crystal - just using the internal oscillator? Does the prop boot ROM do something similar (during booting/programming) that I have described above:
Grateful for any comments!
Cheers,
Christian
Please pardon me (the prop is still fairly new for me), if I'm asking something obvious. I fully understand that the prop has an built in oscillator that can be used instead of an external XTAL, but with fairly high tolerances in clock frequency.
I plan to use the prop with the internal oscillator in an UART application in such a manner, that the prop measures the length of a received break signal at the uart Rx terminal. The prop measures the length of the break and adjusts its receiver clock accordingly. I know how to program this.
My question is:
Can the propeller and the accompanying external program EEPROM be serially booted and/or programmed - without a precise external crystal - just using the internal oscillator? Does the prop boot ROM do something similar (during booting/programming) that I have described above:
Grateful for any comments!
Cheers,
Christian
Comments
The Prop does not use the external crystal during program loading, even if one is there. So, no, you don't need one to upload and reprogram the EEPROM.
-Phil
That is what I assumed - so I can go forward with my project - and leave the XTAIL out - great! By the way - Is the boot code available somewhere? Would be nice have it to understand better the prop... To my understanding this code is hidden but someone has been able to decode it - or ?
Christian
When I stared my first ever experiments with the Prop I basically only had a DIP Prop chip, power supply, decoupling caps and transistor serial loader circuit on a piece of strip board. Oh, together with a LED and resistor to see if anything worked. With that and the Prop tool you can start writing and running programs.