raspberry pi for packet radio


ve2hom <ve2hom@...>
 

Hello all,
I have a raspberry pi and I want to use it for making a packet radio server. I have think to use jnos2 and I want to connect it with my mfj-1270c tnc. This one have a ttl port on the back, can I connect it directly to the GPIO port of the raspberry pi?

Other question, if I try to use a usb to serial adaptor when I attach the port an arror says "protocol error", don't know if it's because jnos don't like usb serial port. Any clue?

Tnx
73' de Pascal
ve2hom


John G8BPQ
 

Pascal,
 
The PI GPIO pins operate at 3.3 volts, and the PI is likely to be damaged by applying 5 volts from a normal TTL port. You will need a level converter on the TNC to PI lead. I used a simple resistor divider. Most TTL inputs are happy with the lower voltage from the PI.
Normally the PI linux kernel allocates the serial port as a console. You need to disable this to use it for packet.
I've used the linux ax.25 and netrom code, and the linux node. I haven't tried jnos.
 
73,
John
 


From: Raspberry_Pi_4-Ham_RADIO@... [mailto:Raspberry_Pi_4-Ham_RADIO@...] On Behalf Of ve2hom
Sent: 08 September 2012 18:30
To: Raspberry_Pi_4-Ham_RADIO@...
Subject: [Raspberry_Pi_4-Ham_RADIO] raspberry pi for packet radio

 

Hello all,
I have a raspberry pi and I want to use it for making a packet radio server. I have think to use jnos2 and I want to connect it with my mfj-1270c tnc. This one have a ttl port on the back, can I connect it directly to the GPIO port of the raspberry pi?

Other question, if I try to use a usb to serial adaptor when I attach the port an arror says "protocol error", don't know if it's because jnos don't like usb serial port. Any clue?

Tnx
73' de Pascal
ve2hom


kc7klz
 

Hi,

I used a USB to Serial adapter.  I did get it to work sort of.  I was attaching to my Kantronics KPC-3 through minicom.  I could get it to recognize the serial port, but when I slowed it down to 1200 baud, it crashed. (locked up)  I had to log into the unit via SSH and tell it to re-boot to get the unit to recover.  I'm getting a TTL to serial adapter, and I'm going to hook that up to the GPIO ports.  I'm thinking this will be a little cleaner than an adapter.  

I can get it to work on my Ubuntu box with the same cables, using the same software.  So I know it should work.

'73

Eric Scott
KC7KLZ


From: John Wiseman
To: Raspberry_Pi_4-Ham_RADIO@...
Sent: Saturday, September 8, 2012 11:14 AM
Subject: RE: [Raspberry_Pi_4-Ham_RADIO] raspberry pi for packet radio

 
Pascal,
 
The PI GPIO pins operate at 3.3 volts, and the PI is likely to be damaged by applying 5 volts from a normal TTL port. You will need a level converter on the TNC to PI lead. I used a simple resistor divider. Most TTL inputs are happy with the lower voltage from the PI.
Normally the PI linux kernel allocates the serial port as a console. You need to disable this to use it for packet.
I've used the linux ax.25 and netrom code, and the linux node. I haven't tried jnos.
 
73,
John
 


From: Raspberry_Pi_4-Ham_RADIO@... [mailto:Raspberry_Pi_4-Ham_RADIO@...] On Behalf Of ve2hom
Sent: 08 September 2012 18:30
To: Raspberry_Pi_4-Ham_RADIO@...
Subject: [Raspberry_Pi_4-Ham_RADIO] raspberry pi for packet radio

 
Hello all,
I have a raspberry pi and I want to use it for making a packet radio server. I have think to use jnos2 and I want to connect it with my mfj-1270c tnc. This one have a ttl port on the back, can I connect it directly to the GPIO port of the raspberry pi?

Other question, if I try to use a usb to serial adaptor when I attach the port an arror says "protocol error", don't know if it's because jnos don't like usb serial port. Any clue?

Tnx
73' de Pascal
ve2hom




 

Are you using a powered hub? (The Pi doesn't source a lot of current.)

http://elinux.org/RPi_VerifiedPeripherals


John D. Hays
K7VE
PO Box 1223, Edmonds, WA 98020-1223 
  



On Sat, Sep 8, 2012 at 12:28 PM, Eric Scott <kc7klz@...> wrote:
 

Hi,

I used a USB to Serial adapter.  I did get it to work sort of.  I was attaching to my Kantronics KPC-3 through minicom.  I could get it to recognize the serial port, but when I slowed it down to 1200 baud, it crashed. (locked up)  I had to log into the unit via SSH and tell it to re-boot to get the unit to recover.  I'm getting a TTL to serial adapter, and I'm going to hook that up to the GPIO ports.  I'm thinking this will be a little cleaner than an adapter.  

I can get it to work on my Ubuntu box with the same cables, using the same software.  So I know it should work.

'73

Eric Scott
KC7KLZ


Pascal Lafond <ve2hom@...>
 

Hello John,
    Yes my usb hub is powered

73 de Pascal
ve2hom

Le 08/09/2012 16:20, John D. Hays a écrit :
 

Are you using a powered hub? (The Pi doesn't source a lot of current.)


http://elinux.org/RPi_VerifiedPeripherals


John D. Hays
K7VE
PO Box 1223, Edmonds, WA 98020-1223 
  



kc7klz
 

I tried both ways.  Seemed to work better when I plugged it in direct.



On 2012-09-08, at 1:20 PM, "John D. Hays" <john@...> wrote:

 

Are you using a powered hub? (The Pi doesn't source a lot of current.)


http://elinux.org/RPi_VerifiedPeripherals


John D. Hays
K7VE
PO Box 1223, Edmonds, WA 98020-1223 
  



On Sat, Sep 8, 2012 at 12:28 PM, Eric Scott <kc7klz@...> wrote:
 

Hi,

I used a USB to Serial adapter.  I did get it to work sort of.  I was attaching to my Kantronics KPC-3 through minicom.  I could get it to recognize the serial port, but when I slowed it down to 1200 baud, it crashed. (locked up)  I had to log into the unit via SSH and tell it to re-boot to get the unit to recover.  I'm getting a TTL to serial adapter, and I'm going to hook that up to the GPIO ports.  I'm thinking this will be a little cleaner than an adapter.  

I can get it to work on my Ubuntu box with the same cables, using the same software.  So I know it should work.

'73

Eric Scott
KC7KLZ

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