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Hello, I can't get the chip you used in your project (ATA6631) however i can get Philips TJA1020. Below you can see the example application note - my question is if there will be a lot of code change if i will use this chip instead of your chip, or is that chip is limited with some functions compared to your chip? I think that the only change will be the fact that: pin 4 TXD from TJA1020 will be your LIN_TX pin 1 RXD from TJA1020 will be your LIN_RX

Hi,

Have you looked at the ATA6625 ?

Somebody suggested once that it may be a pin compatible replacement but I never tried it myself.

Zapta

On Thu, Mar 3, 2016 at 10:08 AM, slabiak [email protected] wrote:

Hello, I can't get the chip you used in your project (ATA6631) however i can get Philips TJA1020. Below you can see the example application note - my question is if there will be a lot of code change if i will use this chip instead of your chip, or is that chip is limited with some functions compared to your chip? [image: tja1020] https://cloud.githubusercontent.com/assets/16743238/13503878/027d6c24-e172-11e5-8ddb-caf0209163ac.png

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10.

I have tried the ATA6625C-TAQYCT-ND (from Digi-key) and it works fine and is pin compatibile. Best regards

Jacek Kukiełło

2016-03-04 2:08 GMT+01:00 Zapta [email protected]:

Hi,

Have you looked at the ATA6625 ?

Somebody suggested once that it may be a pin compatible replacement but I never tried it myself.

Zapta

On Thu, Mar 3, 2016 at 10:08 AM, slabiak [email protected] wrote:

Hello, I can't get the chip you used in your project (ATA6631) however i can get Philips TJA1020. Below you can see the example application note - my question is if there will be a lot of code change if i will use this chip instead of your chip, or is that chip is limited with some functions compared to your chip? [image: tja1020] < https://cloud.githubusercontent.com/assets/16743238/13503878/027d6c24-e172-11e5-8ddb-caf0209163ac.png

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10.

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10#issuecomment-192044820.

Thank you for your answers, it turned out that i have ATA662C in my home so i will use that chip, i have already did a circuit from the application circuit: All i want to do is to do a LINBUS master which will send a frame which normally a control module sends to a car's lamp but i don't have that control module (I want to run that lamp without this module). I know the messege which control this lamp has ID 32 and the data is: "4C FF 32 52 05 00 7A FF" for LO lamp. I dont know how to send that information to the ATA662C so it will convert it to the LIN signal. Can you give me any advice on that? I read somewhere that all i need to do is to send these bytes one after another to serial TX? But it doesn't seem legit to me.

My linbus firmware on github is implemented on the complex side with bit banging in interrupts and such. The reason was that I wanted to have a stack that can can inject signals to frames which was my ultimate goal.

If you just want to control a linbus slave you can probably do it easier using standard serial UART. The only non standard part in the Linbus communication is the break before each frame that typical UARTs cannot do without some trickery.

I would search for other linbus projects that targets having a master (this was not my goal). For example this https://github.com/gandrewstone/LIN

Your master need to do something along these lines:

1. Issue a break signal for the specified time. You can do it for example by switching the UART output pin to be a standard digital output pin and then set it LOW. When done, switch back to UART output. (or any other trick you can think of).
2. Send the entire frame.

A few notes:

1. In linbus, the master doesn't send any data, it's just send the first part of the frame with the id of the salve that need to respond. It's basically going through a polling sequence, asking for responses from slave.
2. Only slaves send data, in response to the master calling their ID.
3. The box with the master can also include one or more slaves. In this case, the same box sends both parts of the frame.
4. Each slave on the bus can see data from all the other salves. Sometimes a slave use signals from multiple slaves for proper operation (e.g. ignition state from one slave and button state from another slave).

Hope it helps,

Zapta.

On Sat, Mar 5, 2016 at 1:41 PM, slabiak [email protected] wrote:

Thank you for your answers, it turned out that i have ATA662C in my home so i will use that chip, i have already did a circuit from the application circuit: [image: ata662c] https://cloud.githubusercontent.com/assets/16743238/13550615/098c5168-e322-11e5-8764-4340a8e24e53.jpg All i want to do is to do a LINBUS master which will send a frame which normally a control module sends to a car's lamp but i don't have that control module - i want to run that lamp without this module). I know the messege which control this lamp has ID 32 and the data is: "4C FF 32 52 05 00 7A FF" for LO lamp. I dont know how to send that information to the ATA662C so it will convert it to the LIN signal. Can you give me any advice on that? I read somewhere that all i need to do is to send these bytes one after another to serial TX? But it doesn't seem legit to me.

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10#issuecomment-192747230.

Well the answer is both yes and no... Yes it's as simple as sending data to a tx buffer (if Your ATA is connected to MCU TX) and No as LIN expects You to send a synchronization break and synchronization field.

Jacek Kukiełło

2016-03-05 22:41 GMT+01:00 slabiak [email protected]:

Thank you for your answers, it turned out that i have ATA662C in my home so i will use that chip, i have already did a circuit from the application circuit: [image: ata662c] https://cloud.githubusercontent.com/assets/16743238/13550615/098c5168-e322-11e5-8764-4340a8e24e53.jpg All i want to do is to do a LINBUS master which will send a frame which normally a control module sends to a car's lamp but i don't have that control module - i want to run that lamp without this module). I know the messege which control this lamp has ID 32 and the data is: "4C FF 32 52 05 00 7A FF" for LO lamp. I dont know how to send that information to the ATA662C so it will convert it to the LIN signal. Can you give me any advice on that? I read somewhere that all i need to do is to send these bytes one after another to serial TX? But it doesn't seem legit to me.

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10#issuecomment-192747230.

Hello, thanks for your answers - it helped me a lot. I used that library mentioned above and now I can send whatever frame I want, for example when i send 0x47, 0x20, 0xf8, 0x73, 0x00, 0x00, 0xcf, 0xff with frame ID 30 i get at LIN output like this: so it seems to be ok. However nothing happens when i send this frame. That's the thing I don't understand. As far as I know to turn on the ligjht I have to send some frame with ID 30 (for example) and some bytes. Which bulb will turn on depends on what bytes I will send. The thing I don't understand is the fact that you said that the master only sends a header (sync, id) and it is the slave who fills the bytes. So tell me how can I say the lamp: turn on LO lamp if I can't send any message to it? I thought that the messeage "turn on the LO lamp" is coded in bytes which master sends.

I presume that you are using the correct baud rate and linbus checksum version (there are two) for your device. Did you look at the linbus signals in the car itself?

When you send the full frame, your box acts as both the master (sending break, sync, id, etc) and the slave of ID 30 (sending the rest of the frame). Hopefully the box you want to control (yet another slave with some other id) read the data from the first slave and do whatever you want.

I know, it's confusing, only slave can control other slaves, master just assign them frames that allow them to send.

The unit that you try to control doesn't necessary accepts 'commands' but respond to bits it see on the bus from one or more other slave. Figuring out what conditions will cause your unit to react is part of the trick of reversing a linbus.

Hope it helps. Anyway, you had major progress being able to send full Lin frames.

Zapta

On Sun, Mar 6, 2016 at 12:22 PM, slabiak [email protected] wrote:

Hello, thanks for your answers - it helped me a lot. I used that library mentioned above and now I can send whatever frame I want, for example when i send 0x47, 0x20, 0xf8, 0x73, 0x00, 0x00, 0xcf, 0xff with frame ID 30 i get at LIN output this: [image: lin] https://cloud.githubusercontent.com/assets/16743238/13556704/d9d7e92c-e3e0-11e5-931a-2855f7f948e2.jpg so it seems to be ok. However nothing happens when i send this frame. That's the thing I don't understand. As far as I know to turn on the ligjht I have to send some frame with ID 30 (for example) and some bytes. Which bulb will turn on depends on what bytes I will send. The thing I don't understand is the fact that you said that the master only sends a header (sync, id) and it is the slave who fill the bytes. So tell me how can I say the lamp: turn on LO lamp if I can't send any message to it? I thought that the messeage "turn on the LO lamp" is coded in bytes which master sends.

— Reply to this email directly or view it on GitHub https://github.com/zapta/linbus/issues/10#issuecomment-192981840.