NewSoftSerial on Mega's pins 2 and 3

Using Arduino Programming Questions
#1

Hi all, I know that only pins that support change interrupts can be used from NewSoftSerial, but for very several problems I cannot change them. I want to know if is it possible to use the NewSoftSerial, changing something, with that pins? Thx,

Marco

#2

First question that comes to mind is this. The Mega has 4 hardware serial ports. Why do you need software serial ports, too?

#3

Is because I want to use this object on both Arduino shield (Mega and Uno).

#4

Is because I want to use this object on both Arduino shield (Mega and Uno).

What object?

#5

The object that I developed

#6

Fell free to volunteer more information. Is this object hardware or software?

#7

it Is hardware: it is a shield for Arduino the uses the pin 2 and 3 on Arduino 2009 for the soft serial. Now I want to use it on a Mega (for many reason for example: to have more RAM) but I read that softserial can’t be used on that pin but I want to be sure for what I read and maybe if there is some trick (maybe hard at low level) to use that pins with softserial. I prefer this istead of rebuild the entire shield.
Thanks,

Marco

#8

I prefer this istead of rebuild the entire shield.

Just run a jumper from pins 2 and 3 to the RX1/TX1 pair on the Mega, and use Serial1 instead of a NewSoftSerial instance.

There is a version of NewSoftSerial floating around that works on some pins on the Mega. I don't remember which pins it does and does not work with. But two wires to the hardware serial port is much easier.

#9

http://arduiniana.org/2011/01/newsoftserial-11-beta/

Note: Not all pins on the Mega and Mega 2560 support change interrupts, so only the following can be used for RX: 10, 11, 12, 13, 50, 51, 52, 53, 62, 63, 64, 65, 66, 67, 68, 69

#10

The only pins in common between the UNO and the Mega that NewSoftSerial 11 is compatible with are 10 to 13, which are the SPI pins. I really wouldn’t recommend reserving any of them for your shield.

#11

Oh thanks to everybody, the problem of jumpers is that this is a product that is already in production phase (hundreds items) so it could be a problem. I try with all my forces to resolve this by software so it can be transparent to the user.

PaulS: There is a version of NewSoftSerial floating around that works on some pins on the Mega. I don't remember which pins it does and does not work with. But two wires to the hardware serial port is much easier.

This can be a very important thing. Maybe I can ask direct to the newsoftserial developers :) Thanks I'll post their reply. Marco

#12