Storing Info in the SX

SailerMan · 2007-03-09 02:07

I need a way to store setting in the SX28.· I can create Data Statements to create the Default, but I want to be able to configure the setup using the serial connection I have.

I am Sending "!CMD" then I will send a Command number and a setting and I want to store it in the SX28 even if power is removed I want it to stay.

Can someone help...Again.. [noparse]:)[/noparse]

Regards,
Eric
·

JonnyMac · 2007-03-09 02:33

You're going to have to attach an external EEPROM. SX/B has I2C functions that make using them pretty straightforward.

Bean · 2007-03-09 03:05

Eric,
The flash memory on the SX doesn't work like EEPROM. It requires a high voltage to program (that the SX-Key/SX-Blitz provides).
There is no way the SX can change it own flash memory.

Bean.

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Cheap used 4-digit LED display with driver IC·www.hc4led.com

Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

SailerMan · 2007-03-09 03:19

OK... Thanks...Which EEPROM works well with the SX-28.

Mike Green · 2007-03-09 04:13

Any I2C EEPROM should do. Whatever is large enough for the amount of data you need to store. The part numbers mostly start with 24LC, then a number like 16, 32, 64, 128, 256, 512, 1024. This number is the number of bits in the device. Divide by 8 to get the number of bytes. The largest current devices are 128K bytes. The theoretical maximum using the current addressing scheme (8 device addresses, each with a two byte address) is 512K bytes.

JonnyMac · 2007-03-09 06:20

If you look in the help file under any of the I2C commands there's a circuit and demo code for the 24LC16, a 2K device that you can get from Parallax.

SailerMan · 2007-03-09 12:20

OK thanks... I hope the 24LC16 comes in a SMT design.

Bean · 2007-03-09 13:07

Eric,
You don't say how many bytes you want to store, but I have a bunch of 24C00 EEPROMs.
They only hold 16 bytes though. I'll mail you some if you can use them. They are SOT23-5 size.

Bean

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Cheap used 4-digit LED display with driver IC·www.hc4led.com

Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

SailerMan · 2007-03-09 13:51

Bean,

Are you serious? Yeah for this project I'm only gonna need a few bytes.

I'll PM you a mailing Address.

Regards,
Eric

Bean · 2007-03-09 14:13

Eric,
How many do you need ?
You don't need to pay me anything for them, I'll just pop them in an envelope.
I have a whole reel of them.

Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Cheap used 4-digit LED display with driver IC·www.hc4led.com

Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

SailerMan · 2007-03-09 16:35

Bean,

I don't feel right about taking them... How about 5 or 10... They seem like they are going to be handy.

Thanks for this, If I need more how much are you asking?

Eric

Bean · 2007-03-09 17:13

Eric,
I got a reel of several thousand from Ebay for cheap.
I'll send you a bunch, the postage stamp would cost more than 10 pcs [noparse];)[/noparse]

Bean

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Cheap used 4-digit LED display with driver IC·www.hc4led.com

Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

SailerMan · 2007-03-09 18:14

OK thanks... [noparse]:)[/noparse] I'll look for them.

Eric

Henry Casson · 2007-03-10 17:33

Most likely this is a dumb question. Can this sort of external memory allow the SX28 to run a program longer than can fit in the existing memory ? Henry.

PJAllen · 2007-03-10 18:42

Can this sort of external memory allow the SX28 to run a program longer than can fit in the existing memory?
No, but if your program·involves using·DATA/WDATA then that all can be stored in an external memory leaving more EE/Flash available.

SailerMan · 2007-03-12 14:03

Bean,

Do· you have sample code that works with these and the SX-28?

Regards,

Eric

RobotWorkshop · 2007-03-12 16:16

Hello Eric,

Have you seen the EEPROM sample code in SX/B on the following post:

http://forums.parallax.com/forums/default.aspx?f=7&m=172860&p=1&ord=a

It may help you get the external EEPROM up and running a bit faster. You should be able to prototype and test with a DIP version of the chip and then go to a surface mount part for your final design.

Best Regards,

Robert

JonnyMac · 2007-03-12 16:34

Details can be found in here: http://www.robotstore.com/download/276568catalyst.pdf

The help file code can be adapted easily -- it looks like the only change is that the 24C00 just uses one address byte versus two in the 24LC16B.

Post Edited (JonnyMac) : 3/12/2007 4:50:25 PM GMT

Bean · 2007-03-12 16:37

Eric,
They are pretty standard. Here is the datasheet http://ww1.microchip.com/downloads/en/DeviceDoc/21178F.pdf
They are 24LC00T/OT devices and I sent you 50 or so today.

For a write you do:

START
SEND $A0
SEND addr ' 0 to 15
SEND data ' 0 to 255
STOP
PAUSE 5 ' Allow time for device to write data

For a read you do:

START
SEND $A0
SEND addr ' 0 to 15
START
SEND $A1
READ bytevar
STOP

Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Cheap used 4-digit LED display with driver IC·www.hc4led.com

Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com

Post Edited (Bean (Hitt Consulting)) : 3/12/2007 4:41:52 PM GMT

SailerMan · 2007-03-12 16:55

Thanks all... It was a little odd in reading an Address... Thanks for clearing that up.

Bean... Thanks for everything.

Eric

egp · 2007-03-16 16:09

Bean,

I'm wondering if I sent you some stamps to cover postage, would you be willing to send me some of those 24LC00T/OT devices?
If so, send me an email to (egp at egp dot net) with your snail mail address, and I'll send you some stamps and my snail mail address.

Bean · 2007-03-16 16:35

Send me a private message with your mailing address.
Just consider it a early birthday present [noparse];)[/noparse]

Bean.

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"A problem well defined is a problem half solved"

"Just because you're approved, doesn't mean you can afford it."
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Cheap used 4-digit LED display with driver IC·www.hc4led.com
Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

egp · 2007-03-16 16:46

Thanks, Bean, that's very generous of you. I sent you a separate email with my snail mail address.

SailerMan · 2007-03-21 15:45

OK I believe that I jumped too Quick... I laid out my circuit and etch a board with the SX and a 24C00 Eeprom... I'm, guessing it's not working because I don't have Pull up resistors on the SCL and SDA line... Would this be a good assumption?

JonnyMac · 2007-03-21 16:13

Yes, I2C requires pull-ups (usually 4.7K) on the SCL and SDA lines. The idea behind I2C is that the transmitting device pulls the line low, the pull-up handles the high. That way if two devices transmit at the same time there is no electrical problem (as there would be if the transmitter drove the line high).

SailerMan · 2007-03-21 16:17

That's what I thought... Darn!!! All of those darn holes drilled. Hahahaha Thanks for confirming that.

Bean · 2007-03-21 16:19

Eric,
Depending on many factors you MIGHT get away with just enabling the internal pull-ups on the SDA and SCL pins.
I don't recommend depending on it, but with some devices it does work.

Bean.

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"Educate your children to self-control, to the habit of holding passion and prejudice and evil tendencies subject to an upright and reasoning will, and you have done much to abolish misery from their future and crimes from society"

Benjamin Franklin
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Cheap used 4-digit LED display with driver IC·www.hc4led.com
Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
Coming soon! Propeller based OSD module www.hittconsulting.com
·

SailerMan · 2007-03-21 17:54

I'm using the SX48 with one 24C00 that you sent me... I will try that. Good Idea as usual.

SailerMan · 2007-03-21 22:21

I am Using a 24C00 and I have SDA Connected to RD.4 and SCL Connected to RD.5 on the SX48
I am trying to run this code.

An LED will flash if the Code written to and returned from the EEProm is the same.

I don't have external Pull up resistor connected only the internal.

Should the Code below work? If so I'm going to have to redesign my circuit.

Thanks in Advance,
Eric

DEVICE          SX48, OSCHS2, BOR42
FREQ            4_000_000

ID  "24C00"
 
Pullup RD.4
Pullup RD.5
 
Sample Var Byte
 
PROGRAM Start NOSTARTUP
Start:
 I2CStart RD.4
 I2CSend  RD.4,$A0
 I2CSend  RD.4,0
 I2CSend  RD.4,170
 I2CStop  RD.4
 Pause 50               
 
Do
 I2CStart  RD.4  
 I2CSend   RD.4,$A0
 I2CSend   RD.4,0
 I2CStart  RD.4
 I2CSend   RD.4,$A1
 I2CRecv   RD.4,Sample,0
 I2CStop   RD.4

 If Sample=170 Then  
     Toggle RD.7
  Pause 100
 Endif 
Loop

·OK I carefully added some External Resistors...They look like Smile but assume it will work.

I still can't read the value of "Sample" as 170

Attached is an O-Scope attached to the SDA and SCL line.

Can anyone offer a solution.

Regards,
ERic

Post Edited (SailerMan) : 3/21/2007 11:48:30 PM GMT

JonnyMac · 2007-03-22 00:31

Check your connections.

And I think your NAK bit is set incorrectly -- on the final byte read it should be 1, not 0 as in your listing.

And... it is very dangerous to embed "magic numbers" -- including pin numbers -- into your listings; HUGE bug generator. Try this version:

DEVICE          SX48, OSCHS2, BOR42
FREQ            4_000_000
ID              "24C00"

SDA             PIN     RD.4
SCL             PIN     RD.5  
Led             PIN     RD.7
 
sample          VAR     Byte

 
PROGRAM Start NOSTARTUP

Start:
  PULLUP SDA
  PULLUP SCL

Main:
  I2CSTART SDA
  I2CSEND  SDA, $A0
  I2CSEND  SDA, 0
  I2CSEND  SDA, 170
  I2CSTOP  SDA
  PAUSE 10

  DO
    sample = 0
    I2CSTART SDA
    I2CSEND  SDA, $A0
    I2CSEND  SDA, 0
    I2CSEND  SDA, $A1
    I2CRECV  SDA, sample, 1
    I2CSTOP  SDA

    IF sample = 170 THEN
      TOGGLE Led
      PAUSE 100
    ENDIF
  LOOP

  END

SailerMan · 2007-03-22 01:40

I am usually careful about my wiring, but I totally missed a ground jumper. Ugh! Works now...I could just slap myself silly now!!!!

Thanks Jonny

Storing Info in the SX

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