Re: EED0 signal state at power up
Bryan Armstrong <bryan.armstrong-6tN4nzCoH/[email protected]>
| Newsgroups | gmane.comp.hardware.microcontrollers.tini |
|---|---|
| Message-ID | <[email protected]> |
Massimo Piovera wrote: > If the SMC chip has control during power up, why do not change the state > set by setDTR(true) function to a +5V intead 0V ? > Obviously I talk because I'm building my new board and I may change > my hardware. The people that already use TINI on his hardware may have > some problem changing the state forced by setDTR(true), but.... The SMC port pins default to 5V on reset which drives the RS232 signals (DTR and RTS) to -10V. As soon as your code calls the flow control enabling function, the SMC chip is instructed to drive the lines to 0V which drives the RS232 signals to +10V. Until instructed, the SMC chip will not change the state of the pins. The SMC reset state cannot be changed. Also consider the possibility that the SMC chip may be held in reset indefinitely because of a low power condition (power not within 5V+-5%). This will put the flow control lines in the default state with no possibility of program control of the condition of the flow control lines. -- -- Bryan Armstrong bryan.armstrong-6tN4nzCoH/[email protected] _______________________________________________ TINI mailing list TINI-6tN4nzCoH/[email protected] To UNSUBSCRIBE, edit your profile, or see list archives: http://lists.dalsemi.com/mailman/listinfo/tini