multiple serial ports needed in micro controller

[shahbaz.ele]

dear all
I need to have more than 10 serial ports for data reading.
If I use microcontroller (uc), can algo be written for serial port through a normal I/O pin.
If some one tried it earlier please share the idea here.

 

[vinodstanur]

Basically you need external interrupt pins or timer input capture for writing software UART RXI for the microcontroller.
To emulate UART TX is much easier because you can use any GPIO for that.. Just need a timer to control the timing...

So you need RX or TX ? Or both?
RX means RX in microcontroller where the controller receives data from external UART device...

 

[shahbaz.ele]

I just need to recieve the data from a device which outs as RS232 formate.
no need to Tx from controller.

 

[vinodstanur]

See this application note from Atmel, it may help you to implement it yourself.
**broken link removed**

 

[Raady Here]

dear all
I need to have more than 10 serial ports for data reading.
If I use microcontroller (uc), can algo be written for serial port through a normal I/O pin.
If some one tried it earlier please share the idea here.

I didnt work,but you can use GPIO expander for this !

 

[Analog Ground]

The original post specifies 10 serial ports. Are they active at the same time? What are the baud rates? This many software serial ports are probably not practical in a single microcontroller.

 

[shahbaz.ele]

The senario is that there are multiple devices working around.
they all are interfaced on a single board for action (decision making).
I thought to use uc to receive that data from all devices.
baud rate 9600.

 

[nandhu015]

The senario is that there are multiple devices working around.
they all are interfaced on a single board for action (decision making).
I thought to use uc to receive that data from all devices.
baud rate 9600.

Still you havnt answered important question by analog ground.
Will all the ports active at the same time?

 

[udhay_cit]

You are talking about "Software UART". Do the google search for a specific controller with the keyword of software UART. If all other devices are microcontroller & designed by you, then its better to go for MODBUS protocol...

Regards
Udhay

 

[betwixt]

If all 10 are active at the same time and sending at 9600 bauds I doubt a soft UART would work as well as having time to do something with the data it has received. It might be better to either dedicate a micro as a multi-channel UART and give it an SPI like interface to it's host or better still, use multiple hardware UARTs such as the MAX3100 or it's sucessors.

Brian.

 

[udhay_cit]

You can use Cypress semiconductor microcontroller (PSoC 1, PSoC 3 or PSoC 5). I'm using PSoC 1 for my application. It has 16 Digital configurable blocks(UDB). You can configure all the 16 blocks as UART. Otherwise you can use it as I2c, SPI or any other protocol & configurations. All the pins are re-mappable. operates from 0.5V to 5.25V, configurable ADC(upto 14bit) & lot of features...

Anyway it will solve your UART problem. Sample code also available for multiple UART. You can try with this...

 

[shahbaz.ele]

from all above discussion, it seems to me that I must go for some other option
Like FPGA, because of speed and parallel processing ( all devices are sending data at asame time).
is it so ?

 

[Analog Ground]

from all above discussion, it seems to me that I must go for some other option
Like FPGA, because of speed and parallel processing ( all devices are sending data at asame time).
is it so ?

Have you considered UART devices? NXP makes a chip with four serial ports which are fully buffered. Then you will have a proven and well documented solution. Throw on three chips and your done!

 

[shahbaz.ele]

@ Analog Ground

can you suggest any part no.
its interesting thing.
if this type of IC is available then why to go for FPGA.

 

[Analog Ground]

To my knowledge, NXP has the most number of parts. They even have an 8 channel unit. See:

https://www.nxp.com/products/interface_and_connectivity/uarts/

There is also the Maxim MAX14830 which is a 4 channel part.

 

[shahbaz.ele]

Thank you dear @ Analog Ground
let me explore these. then report here.