Basic Stamp Questions

Slugg

Hi,
I have a couple of questions regarding the basic stamp.

1) Can I program the basic stamp on a BOE (for example) the pop it into a self made board to execute the program? Basically, I'm trying to avoid buying a BOE for every project I want to use a BS2 with.

2) Where can I find the schematic for building my own 'BOE"? I found a link for this on the faq...but it was a dead link..:-(

3) What options do I have for two BS2's to communicate? For example, for one to run the Navigation system of a small bot while another runs User Input/Output (LCD, pushbutton, text-to-speech...etc) I assume I can, if nothing else, use SERIN/SEROUT commands...but how about I2C? Is I2C a plausible method for two stamps to communicate?

I appreciate your help.
Regards,
Slugg

allanlane5

1. Yes. The BS2 carries its program with it (as well as it's own linear regulator, for that matter) so you can 'pop' it into your own board. Note that there's a "Super Carrier Board" made by Parallax which is good for this.

2. The BS2 PBasic manual used to have a schematic in it for the BOE board.

3. The BS2 works great using SERIN/SEROUT communications, both as 'master' and 'slave'. The BS2 cannot be an I2C or SPI 'slave' device, so that rules that out. Note the SERIN/SEROUT commands also have an 'Open' baud mode, which lets you use them on a 'party line', 'multi-drop' interface.

Slugg

Sweet! Those are the answers I wanted to hear!!!!

RDL2004

For the lowest cost solution, take a look at the BS2 OEM. It's pretty much just a larger version of the BS2 with the serial port connector and a more heavy-duty power supply included. Every part is thru-hole and easy to work with. The two are functionally identical.



Your program is actually stored in the eeprom chip. Other than the interpreter chip and resonator, pretty much everything else on the BS2 OEM board is for the programming interface and the power supply. Once you program the eeprom, you can take it and place it in another circuit along with an interpreter chip (it doesn't have to be the same one), resonator, and a 5 volt power supply and you're good to go. In some cases you may want to include the brown-out detector for low voltage reset, but it's not absolutely necessary.

If you really need to pinch pennies, you can get eeproms, resonators, and the other parts from a distributor such as Mouser or Digi-Key, etc. The only thing you absolutely have to get from Parallax (or one of their distributors) is the interpreter chip, a plain old PIC won't work, it has to be pre-programmed with the interpreter software.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Rick

RDL2004

In case you don't have a soldering iron, the BS2 OEM is also available assembled.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Rick

Forrest

Parallax sells a few different development boards - a few cost a lot less than the BOE. The Super Carrier board has a similar layout and many of the same features as the BOE - but it only costs $20 www.parallax.com/detail.asp?product_id=27130. Solder (4) 3 pin headers into the SuperCarrier board and you could run (4) servo's, PING modules, Serial LCD's, etc www.parallax.com/detail.asp?product_id=805-00012

RDL2004

I should have pointed out that the lowest cost only comes after the first BS2-OEM, that one is $30 (plus a few dollars postage), but then you can use it as programmer for additional eeproms and duplicate what the the standard BS2 does relatively cheaply. The interpreter chip is $11 from Parallax (in singles, postage extra), the rest depends on where and how many of the component parts you buy and what kind of shipping you have to pay. In quantity, you could probably reproduce the functionality of BS2 for under $15, assuming you don't need all the extras. And... if you really wanted to, you could DIY the BS2-OEM in the first place, but I really don't think the trouble that would be worth the few dollars you would save.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Rick

Slugg

Okay,
lemme see if I'm understanding everything correctly.

I could use my current BOE to program my BS2....remove the BS2 and pop it into a project (and just provide the power requirments needed for it to run). I could then get another BS2 and program it in the same BOE to place in a different project?

Is that correct?

Now that I'm thinking this portion through, it would be a pain in the butt to have to remove the BS2 to program it...so I could use the OEM as a 'substitute' BOE for all my projects...and just program them while they are in their final home (assuming I left the OEM installed).

So instead of buying a BOE for every project, I could buy a BS2 and an OEM for every project...

Do I have all this right?


I appreciate you all spelling this out for me. I live in a very remote area, and I hate to order things just to find out I have to wait for another order to process before I can move forward with projects.

Regards,
Slugg

Forrest

There are many ways to solve this problem. The BS2OEM can easily be swapped from board to board - but keep in mind you'll have to design your boards specifically for the BS2OEM (which can't be installed directly into a BOE or a SuperCarrier Board).

Another option is to split the BS2OEM onto two boards. One would contain the BS2 Interpreter ($11), 20 MHz Resonator ($2.48) and the EEPROM ($5) listed at the bottom of this page www.parallax.com/detail.asp?product_id=27291

The programming portion of the BS2OEM could be placed on a second board (resistors, 3 transistors, etc) - check the schematic from my link above. The P1 Programming Adapter is one such design www.wulfden.org/pa/index.shtml. The programming board only needs to be attached when you want to reprogram the BS2 - and can be disconnected afterwards.