[atmel]

I want to try to get this chip programmed and to work, but my knowledge for programming is terrible
I'm trying to get the atmega8a-au to work with this ( my old ) project
So what kind of X-tal can i use 8 or 16Mhz. and what program should i use
I use ponyprog with parallel isp, works well.
i found the mega8 files from older postings, after reading the asm i see that the basic file is compiled as 16mhz. i should use a 16Mhz x-tal?

yeah i need some help how to programm cause there are 2 hex files, and the fuses to set?
1 chip is lost by playing with wrong fuses.

( I can help with pcb's prototypes and small series. parts also obsolete parts)

[atmel]

its working fine up to about 200rpm then loose position, motor could do 3000rpm encoder is 200ppr. encoder with scope checked nice pulse on high speed.
the hex and eep from the first posting is used for the atmega8.

the tuning software does not work, no connection.
i used the max232 for rs232/uart.
could use some assist when someone have time??

gr roel

[krazatchu]

@ Atmel: Wow, your selling boards I designed so long ago...
The original boards are on my website: DC Servo Drive | Krazatchu Design Systems

I'm working on a new DC servo layout with new software...
When the design is ready, I will post it on http://n0m1.com

Michael

[gman2707]

Hi,
I have built this servo board with ATmega48_20MHz_v3_5. Everything is working fine, except that I can´t connect with servotunning. Is it possible to get it work on Windows 7? I tried run serial port terminal and it looks alive, so the configuration should be OK. Black color is received from driver, pink is send to driver (attachment 1). If I try to connect to the servotunning, i get an error message (attachment 2). Any ideas what could be wrong?
I tried also the older version ATmega48_16MHz_v3_4, but no change.

Is it possible to tune the driver right from terminal? How should the command frame look like ?

[krazatchu]

@ gman2707

If you look at the the source file, "Servo_Mg48_20Mhz_v3_5.asm" using a text editor (or programmers notepad)...
Starting after line 556 you will find the input commands for serial...

If you follow each command to the jump, you can also determine what arguments each command is looking for...

In_Message:
lds r16, UART_COMMAND

cpi r16, 'p' ; Get Position
breq do_get_position

cpi r16, 'V' ; Get Velocity and 1kHz counter
breq do_get_vel_1khz_cnt

cpi r16, 'B' ; Set sub-command
brne PC+2
rjmp do_set_sub

cpi r16, 'P' ; Set Position
brne PC+2
rjmp do_set_position
.
.
.

For this exact reason, I will be implementing a set of tuning potentiometers on my next DC Servo PCB. No computer required for tuning...
I have posted a preliminary layout here: http://n0m1.com/2011/11/19/nomi-locus-dc-servo-kit/

Michael
http://www.n0m1.com
htp://www.krazatchu.ca

[mo7]

hello every body i had make the pcb for 20 MHZ controller it work nice with pwm and velocity put it does not work in position because of the encoder i Measured the voltage across a and b channel when it disconnected to the board it gives 5v pulses but when i connect it the voltage goes to to 0.2v i does not used the nand shmitt curcuit does it effect?
please any body help me and thanx

[krazatchu]

mo7, Show your schematic and board if you want help...
And whats the model of your encoder?

Also, I believe the velocity mode also uses the encoder, only voltage mode works without the encoder...

Michael
http://www.n0m1.com
http://www.krazatchu.ca

[moghul]

HI mo7 u have must pullup 4.7k resistor at encoder A and B line . 4.7k to +5v supply.
then it will be go to +5. and also show encoder input diagram.
shabbir
[email protected]

[mo7]

thank you guys and this is my schematic and michael yes vilocity needs encoder thank u and thanx moghul

[moghul]

Hi mo7
how r u?
thanks for schematic but it is only power side. its nice but on option. u can also use sd pin of gate drive 2184 for oc shutdown but ur diagram also nice and OK.
is ur encoder problem clear?

[krazatchu]

@moghul

Scroll down, the rest is on pages 2 & 3...

Michael
http://n0m1.com/
Krazatchu Design Systems

[moghul]

sorry guys i was not scroll down. now i have checked. it nice but my friend in here have made this and also not work encoder. i worked on tn2313 and drive motor at full and accurate position. i use pull up 4.7k at encoder input and then goes to 7414 then into the controller. it works nice no error at any time. i will send u diagram. ok

[krazatchu]

I have converted Chan's encoder polling function to inline assembly for use within C.
It's considerably more portable this way and is released under GPL.
It's been testing @ 100kHz along side a 1kHz PIV loop written in C and it seems to be behaving nicely....

It's at: http://n0m1.com/2011/12/21/inline-as...ature-decoder/

I've also written a tuning program in Processing, using a bump disturbance on the servo and then capturing 1/4 second of position data at 1kHz...
That makes for some really nice position graphs but I'll leave that for another post/day...

Michael

[moghul]

i have worked on atmega48 with analog in pid. i have done programming and now to assembling my PCB.

[mo7]

thanx guys

[Helmute2000]

Hi Guys,

one question, why not using an ATXmega for the next release? These devices are running with 32MHz a bit faster than the old ones.

Br,
Helmut

[krazatchu]

@Helmut

I think an ARM M3 would be a better choice.
With quadrature hardware, deadtime on the pwm, built in USB...
They are cheaper and faster than the Xmega...

Michael
http://n0m1.com/
Krazatchu Design Systems

[Helmute2000]

Hi,

what is your reason then to stay further on the ATmega? I saw here the ATxmega 16A4-AU costs 4,30€ ATxmega 32A4-AU costs 4,80€.
That's not enough to change the whole development platform isn't it?

An ARM cortex M3 is much more expensive than an ATxmega?

Br,
Helmut

[krazatchu]

The ATmega gets the job done, it's common, not expensive, available in DIP form and lends itself to Arduino compatibility...
I'm making an open source DIY kit (recent update), so the AtMega328 is the part of choice, especially considering the freely available IDE and community support.

With that said, if I decide to make pre-assembled board, I might choose the ARM LPC1751, it's got numerous motor control features built in and can be had for about $3.50 in quantity...

LPC1751FBD80 :: NXP Semiconductors
32 bit, 100Mhz, 32k flash, 8k SRAM, USB, quadrature decoding hardware, motor control pwm, etc..

It probably makes the Xmega cry itself to sleep....

Michael
http://n0m1.com/
Krazatchu Design Systems

[moghul]

ATXmega is not AVAILABLE in Pakistan