Agree. Microchip did the same thing too on dsPICs. I just hate it. This is a Very very bad documentation practise. It is very hard to find the info you need, and some time the documents conflict with each other. Funny N. Au Group Electronics, http://www.AuElectronics.com http://www.AuElectronics.com/products http://augroups.blogspot.com/ ________________________________ From: M. Adam Davis To: Microcontroller discussion list - Public. Sent: Tue, March 2, 2010 8:42:22 AM Subject: Re: [EE] Low cost 32bit MCU, how low is low On Tue, Mar 2, 2010 at 2:07 AM, Wouter van Ooijen wrote: > > since few of the ARM chips are documented in enough detail >> to actually write your own peripheral drivers. > > Which ones? All chips I checked so far are thoroughly documented. I think the main issues are: * Several different document sources * Different peripherals among each manufacturer So if you want a complete picture of one particular device you have to pull down several datasheets and refeence manuals from the manufacturer, then a few reference manuals from ARM to get the complete picture. Even then it's confusing - which manual tells you the interrupt vector for peripheral X? Well, visit the peripheral manual, then the device datasheet, then the register/memory map, then the CPU reference, and eventually, maybe, you'll get your answer. But don't forget that you may have to deal with memory mapping, DMA, etc. Moving from simple 8 bit microcontrollers where everything was in one datasheet to more complex computers on chips is a significant leap. The different peripherals from different manufacturers issue is also a problem. You can abstract your drivers as much as you like, but porting is still a surprisingly significant difficulty. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist