What is the minimum connections for MCF52259 to operate?

[Dglzz]

I want to prepare a self-sufficient breakout board (means having minimum connections to operate and be programmed) for 144-pin MCF52259. 

So power rails and crystal pins are obvious but what are the other essential pins? Especially I am confused about programming part.

Thanks 

[scifi · Accepted solution]

A few weeks ago, I made my first MCF52259-based board. Apart from power supply pins, it is essential to configure clock source out of reset (pins CLKMOD0..1, XTAL.) You have to deassert TEST and RCON as well. I'm also using a power supply supervisor to generate RESET and a CMOS oscillator for external clock. I am using BDM for debugging and flash programming, that's 6 pins total (pins 38-43.) That's all.

Regards,

- mike

[Obetz]

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scifi wrote:

A few weeks ago, I made my first MCF52259-based board. Apart from power supply pins, it is essential to configure clock source out of reset (pins CLKMOD0..1, XTAL.) You have to deassert TEST and RCON as well. I'm also using a power supply supervisor to generate RESET and a CMOS oscillator for external clock. I am using BDM for debugging and flash programming, that's 6 pins total (pins 38-43.) That's all.

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What about JTAG_EN?

Oliver

[Dglzz]

Thanks, it is very helpful, and another question;

If I buy use a low-cost BDM like AxBDM-CF, will I need a 26-pin BDM pinout. Or is there another debug pinout(port) to use that 6 pins(38-43) to program?

[Nouchi]

Hello,

BDM link needs 9 lines, you can build a cable adaptor from 26 pins berg connector to a 10 pins connector with a smaller footprint for your PCB.

You need to keep BKPT, RSTI, DSCLK, DSI, TCLK, DSO, ALLPST, +VCC and GND indeed.

Emmanuel

Message Edited by BugMan on 2009-10-08 09:14 AM

[Obetz]

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BugMan wrote:

BDM link needs 9 lines, you can build a cable adaptor from 26 pins berg connector to a 10 pins connector with a smaller footprint for your PCB.

You need to keep BKPT, RSTI, DSCLK, DSI, TCLK, DSO, ALLPST, +VCC and GND indeed.

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You don't need TCLK and ALLPST for basic BDM debugging. Well, ALLPST saves polling but it's not needed unless the debug adapter insists on using it.

It might be necessary to have TCLK (and JTAG_EN, of course) if you want to unlock a protected device via JTAG, (alternatively you can use EzPort).

Oliver

Message Edited by Obetz on 2009-10-09 09:49 AM

[PabloBaena]

Hi,

I'm having difficulties for programming the MCF52259 in my own board for the first time. I studied the TWR-MCF5525X circuit but my design is not working for BDM connection.  Can't find what is missing

What about the PST[3..0] and DDATA[3..0] lines?

Thanks in advance for your response.