topic Re: bigger eval board than DEMO9S08QG8? in 8-bit Microcontrollers

bigger eval board than DEMO9S08QG8?

irob — Fri, 12 Jan 2007 05:43:18 GMT

Hey everybody. I've loved my Axiom DEMO9S08QG8 demo board. Only problem I have right now is I'm running out of I/O for some bigger projects.

I've looked at the softecmicro PK-HCS08GB60 starter kit. It's also USB, has a row of LEDs, an analog pot, but only one user switch. But there doesn't appear to be a BDM out port to program target parts.

It's based on the MC9S08GB60, so it has four 8-bit ports.

Any other suggestions for a bigger, better demo board?

Re: bigger eval board than DEMO9S08QG8?

Encoder — Fri, 12 Jan 2007 17:53:39 GMT

Hi Irob. I think that you hardly will actually find a better demo board than DEMO9S08AW60 for the same price for the 9S08 family.

It has a lot of I/O on board and many leds and pushbuttons to experiment with other than 2 RS232 and USB BDM. Not to talk of the expensive 64 pin QFP socket which would cost you more than the whole board if bought as a spare part and which is invaluable to permit to replace a possibly blown cpu (unfortunately I found the AW60 quite delicate on the ESD side).

Yes, the accelerometer is completely unusefull but the potentiometer and the light sensor may be good. I have at least 6 or 7 HC08xx demo board but I abandoned all them for DEMO9S08AW60 which permits you to work either on 3 or 5V supply environment and, most af all has BDM interface.

Regards,

Encoder

Re: bigger eval board than DEMO9S08QG8?

OldMan — Fri, 12 Jan 2007 23:51:06 GMT

You can unplug the QG8 chip form the DEMO9S08QG8 and use it as a USB-BDM tool. I used that for a BT16A chip that I wired myself. Works greate. The switches, LEDs, photo-detector, etc. on the DEMO9S08QG8 can be used too.

Re: bigger eval board than DEMO9S08QG8?

irob — Sat, 13 Jan 2007 01:19:36 GMT

OldMan, you are right about the QG8 demo board. It's very nice in that there is the BDM port available. That's what I've been using primarily, but recently ran out of I/O.

Encoder, where can I buy an AW60 demo board? That thing sound great!

Re: bigger eval board than DEMO9S08QG8?

Encoder — Sat, 13 Jan 2007 04:44:38 GMT

Depending where you are, you may easily buy it from DigiKey in USA or from Farnell or RS-components in Europe: all they usually have it in stock and you may have it in a couple of days as I did. The price may slightly vary.

But many other classic distributors like Avnet or Arrow have it. And you may order it also from Freescale Direct Buy Service for 84.99$, but I do not know if its is available in stock.

Informations, electric diagrams, guides and everything are completely available on this Freescale site.

Encoder

Re: bigger eval board than DEMO9S08QG8?

Jaux — Sat, 13 Jan 2007 16:36:02 GMT

Hi Rob,

Due to the same restrictions I have developed my own prototyping board based on the AW60 chip.

Every I/O pin is mapped to the edge connectors and you can optionally switch in the two serial ports via a MAX232, switch in a RS-485 controller and switch in optional driving devices to power and drive a standard LCD module.

You can use almost any xtal - from 32Khz or prefably 9.8304Mhz or even 20Mhz

The BDM connecter is edge-wired seperately

It has an embedded 1A switching supply which can take 9 - 20 VAC input in a "power-over-RS-485" configuration.

Board size is 70 x 95 mm

You are welcome to the design, PCB Gerbers etc.

Let me know

John

Re: bigger eval board than DEMO9S08QG8?

joerg — Sat, 13 Jan 2007 23:55:42 GMT

Hi Rob
since i hate the usual demo boards i have developed the HC(S)08 system. The idea is to have a "mainboard" and different modules for your MPU as well as a lot of "addons" to get started with your prototype. I wanted to include a simple OS witch has become my EBS08 as a base for the software (i am using Motorola/freescale MPU for about 20 years now) having a lot of modules beside. Then for every hardware module i have also the schematics as a module, so once i have finished the software and having tested it i do the layout based on my modules. All this save a lot of time and is kind of foolproof! (at least i do the mistakes normally only once!).
For more infos visit www.systech-gmbh.ch -> HC(S)08 system for the hardware and -> EBS08 for the software. If you need help ask here or send a mail to info@systech-gmbh.ch

Saluti Joerg

Re: bigger eval board than DEMO9S08QG8?

irob — Tue, 16 Jan 2007 00:41:01 GMT

John, thanks for the kind offer. I sent you a private message.

Joerg, your site has quite a wealth of information. I love your module-based approach to the Freescale MCUs. Very cool. Thanks for the help, everyone!

Re: bigger eval board than DEMO9S08QG8?

bigmac — Tue, 16 Jan 2007 00:57:57 GMT

Hello John,

Jaux wrote:

It has an embedded 1A switching supply which can take 9 - 20 VAC input in a "power-over-RS-485" configuration.

I would be interested to find out a little more about the details of your "power over RS485" concept. Thanks in advance.

Regards,
Mac

Re: bigger eval board than DEMO9S08QG8?

Jaux — Tue, 16 Jan 2007 02:29:52 GMT

Mac,

OK - basically what I am doing is using a 4-core screened cable for the multi-drop.

2 + screen is used in RS-485 communication and two wires cary the AC which get regulated, smoothed and switch-regulated to 5 or 3.3V. I have used the 12V lighting transformers with success.

If you need more detail - let me know and I will do a little app-note style technical document.

BR, John

Re: bigger eval board than DEMO9S08QG8?

bigmac — Tue, 16 Jan 2007 08:59:31 GMT

Hello John,

For a moment, I thought you might have been distributing power over the same pair as the communications, or using some sort of common mode arrangement - but realize this is probably not possible for RS485. I have previously used spare pairs on Cat. 5 cable for the purpose of distributing low current DC power, in some cases from a standby battery and battery charger combination. I presume your use of a switching regulator gives much wider voltage compiance than a linear regulator, and with lower dissipation - be it for somewhat higher cost.

I am currently updating the design of my RS485 based equipment, and propose to use an isolated RS485 interface to eliminate earth loops for the wiring to the slave equipment, in a multi-drop master/slave system. To supply power to the isolated side of the interface, I seem to have the choice of using an isolated DC-DC converter supplied from the non-isolated side (expensive?), or to remotely supply the DC power from the common master location. For the latter alternative, it would be hard to justify the use of a switching regulator at each slave.

This was why I was interested in your post. Incidently, I am also thinking of upgrading to the AW32 device (in the 44-pin package) for this project, assuming I can actually get hold of the silicon here (in Australia) - not always possible in more moderate quantities.

Regards,

Mac

Message Edited by bigmac on 2007-01-1611:02 AM

Re: bigger eval board than DEMO9S08QG8?

Jaux — Tue, 16 Jan 2007 16:51:19 GMT

Mac,

Just round the corner from me ( Cape Town, South Africa) - nice see somebody from down South.

I have tried to contrust an arrangement using the data pairs for conveying the AC, but the problem is that in oder to get any reasonable distance on RS-485 one has to watch the baud-rate and even using 115 kB, the seperation from 50 Hz is tricky, and the isolation transformer is bulky, expensive and does not work very well. So the 4-core screened cable is pretty standard what we use for normal RS-232 comms. Also, the 4-Cs cable is cheaper than CAT-5 cable.

I am using a LM2575T (~ USD1.2 ea )( switching regulator soldered directly to a copper-pour area on the PCB. See attached pic. I agree it is a little expensive, but this arrangement take away all headaches of a typlical noisy industrial deployment. Using this arrangement will eliminate your earth-loop problems.

I love the AW60 and AW32 chip - We have standardized on this for all our 8-bit applications. Try asking Freescale for samples if you need one or two for prototyping, or you can buy small quantities directly from Freescale ( shipping however is expensive )

dsc00119.jpg

Message Edited by t.dowe on 2009-09-22 12:00 PM