Re: BL2100 Expansion headers (LCD) to add extra IOs
Stan Hsu <stanley_hsu-/[email protected]>
| Newsgroups | gmane.comp.hardware.rabbit-semiconductor |
|---|---|
| Message-ID | <[email protected]> |
It sounds like you can not use the Aux IO, but use the A0-A3 address lines to indicate write and read and also which chip to read/write. Then just use the PE7 to enable the corresponding chip? AuxIO would do so much of the work for you so it is much easier to realize. In essence, it does not sound too bad but not sure. Also afraid if the SW will interfere somehow with the existing board. ________________________________ From: Scott Henion <[email protected]> To: [email protected] Sent: Wednesday, March 27, 2013 9:57 PM Subject: Re: [rabbit-semi] BL2100 Expansion headers (LCD) to add extra IOs On 3/27/2013 9:40 AM, Stan wrote: > Aux IO is not difficult to program but without it, it seems it will be much slower. Dont know, I have not done much ASM so I do not know how fast doing 8 bit readings would be. External I/O is no different than aux I/O, just uses a different bus. No difference in software other than not enabling aux I/O. There is a global aux I/O control in SPCR. Should not need to be changed. > > Just wanted to see if anyone out there has any experience trying to do this. There is no I/O read or write line, that makes it more complicated. You can use some address as read only and others as write only. -- ------------------------------------------ Scott G. Henion, Consultant Web site: http://SHDesigns.org ------------------------------------------