| ??? 10/03/08 07:40 Read: times |
#158789 - you can't fail with software master Responding to: ???'s previous message |
He probably missed the mark a bit.
Software SPI master is trivial. The master can run the SPI bus at varying speed, i.e. one bit at 100kbit/s, one bit at 10kbit/s, one bit at 1Mbit/s. It is still valid SPI. So a software-only master need not run at hard real-time. The only requirement is that it can guarantee a minimum delay to make sure that it doesn't run the SPI too fast. A SPI slave can not affect the speed of the communication. So it must _always_ be fast enough. And it can not report back to the master that it is busy, since if it isn't fast enough, the master will receive broken information. |
| Topic | Author | Date |
| SPI slave | 01/01/70 00:00 | |
| high speed? | 01/01/70 00:00 | |
| sory for late replay. | 01/01/70 00:00 | |
| SPI clock | 01/01/70 00:00 | |
| not sure.. | 01/01/70 00:00 | |
| the worst possible approach | 01/01/70 00:00 | |
| SPI Slave Response | 01/01/70 00:00 | |
| further explanation? | 01/01/70 00:00 | |
| Fixed speed | 01/01/70 00:00 | |
| SPI Timing Diagrams | 01/01/70 00:00 | |
| UART Mode 0 - SPI like Serial Shif register | 01/01/70 00:00 | |
| uhm | 01/01/70 00:00 | |
| to joe | 01/01/70 00:00 | |
| your point? | 01/01/70 00:00 | |
| you can't fail with software master | 01/01/70 00:00 | |
| Unanswerable! | 01/01/70 00:00 | |
| really? | 01/01/70 00:00 | |
| Intended for/usable for not always identical | 01/01/70 00:00 | |
| consideration? | 01/01/70 00:00 | |
| Some Questions | 01/01/70 00:00 | |
| whichever you choose | 01/01/70 00:00 | |
| low cost? | 01/01/70 00:00 | |
| if you do not use an interrupt | 01/01/70 00:00 | |
| polling? | 01/01/70 00:00 | |
| bits/s not packet size | 01/01/70 00:00 | |
| speed? | 01/01/70 00:00 | |
| bits/s not packet size! | 01/01/70 00:00 | |
| 500ms? | 01/01/70 00:00 | |
| here | 01/01/70 00:00 | |
| Yes - I agree | 01/01/70 00:00 | |
| issues | 01/01/70 00:00 | |
| UART! | 01/01/70 00:00 | |
| Not complex - just requiring low baudrate | 01/01/70 00:00 | |
| kind of rcorrect | 01/01/70 00:00 | |
| Complexity contra recommendable | 01/01/70 00:00 | |
| answer | 01/01/70 00:00 | |
| as i said | 01/01/70 00:00 | |
| lots of them | 01/01/70 00:00 | |
mcu with spi, right here in the thread | 01/01/70 00:00 | |
| CodeArchitect. ? | 01/01/70 00:00 | |
| no | 01/01/70 00:00 | |
| ahhh | 01/01/70 00:00 | |
| simulating SS? | 01/01/70 00:00 | |
| Interrupts are slower than tight polling | 01/01/70 00:00 | |
| wow | 01/01/70 00:00 | |
| all about worst-case | 01/01/70 00:00 | |
| thanks... | 01/01/70 00:00 | |
| missed interrupts | 01/01/70 00:00 | |
| correct me.. | 01/01/70 00:00 | |
| Fast interrupts | 01/01/70 00:00 | |
| thanks... | 01/01/70 00:00 | |
| An Alternative... | 01/01/70 00:00 | |
| Some Descriptive Information | 01/01/70 00:00 | |
| AT89LP2052 has HW SPI | 01/01/70 00:00 |