Help, I can program my HC08GP32 uCs ONLY once ..... :~(

[F4Lc0N]

Hi,

I am using an HC08GP32 uC (actually I have 5 different ones), with a generic programming board (w/MON08 serial port circuitry built in). I use the latest versions of P&E Software (ICS08/PROG08SZ). I used to program them some 4 years ago with no problem, using this same board, but now that I am taking HC08 projects on again, I am having a problem .....

I am able to program NEW microcontrollers, but once I have programmed (and tested them on a protoboard succesfully), I cannot program them again. When I try to connect to the board, to program the S19 file (same file or new one) to the uC, the software keeps on bringing up the widow that says "Attempting to contact target and pass security". When I use "ignoring security failure and enter monitor mode" I get the same result. It always says "Trying Security $FFFFF" ....  and "(Failure of 68HC08 ....)"

I am attaching a screen capture (Problem.JPG) of what I am seeing all the time 

I started working with one specific micro (let's call it #1), which I had already programmed before (years ago) more than 100 times, and I programmed it just fine. But when I wanted to program a new version, it failed. So I thoguht #1 was dead ... I went out and got two more microcontrollers (#2 and #3). If they wouldn't program, the board was damaged, I assumed. But #2 was programmed with no problem, and failed to be programmed a second time. Same thing happened to #3. So I conclude: The board is fine, chips #1, #2 and #3 are fine (I think) because they work on the testing protoboard with the code they have programmed, doing what they are supposed, so the problem is either the software, or, most likely, me, not taking something into account and not configuring something .... (Could it also be something I am doing to the ICs that makes them non-writable ? I hope not ...). It is not only a NEW IC thing, since #1 was old and had something already programmed on it when it worked .....

I am using the latest P&E software (WinIDE, ICS08 and PROG08SZ (v.2.12)), all downloaded from their homepage 2 days ago, running under WinXP SP2  ....

If you need any other info to try to fix the problem, please let me know ..

Any help will be greatly appreciated ....

[rocco]

Hi Falcon,

Check your high voltage, the approximately 8 or 9 volts that gets applied to the IRQ pin in order to enter monitor mode.

A GP32 with a reset vector of 0x0000 will go into monitor mode automatically. If the reset vector is not zero, you need the high voltage on IRQ. That would fit well with your symptom, where blank chips enter monitor mode.

[peg]

Hi Falcon,

Rocco meant FFFF in his reply above.

Another though I had was that you were relying on a self erasure technique previously to enable reprogramming with fewer connections before (no high voltage) and now you are not coding for it.

[rocco]

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peg wrote:

Rocco meant FFFF in his reply above.

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Ah, well, um . . . yeah.

I meant that the reset vector was unprogrammed. I forgot that flash is all 1 when blank.

[F4Lc0N]

Hi,

I checked the voltage on the IRQ pin, using two different 12V (assumed) power sources (one 10.73V, and the other one 18.84V). In both cases, just after turning the board on, the IRQ pin had less than 1.0V, and when PROG08SZ is run (trying to connect to the board for programming) the IRQ pin shows 7.78V with both power sources. Could that be the problem ? Should the voltage there be higher ?

About the coding (I only code in Assembly, not C), I have never used any special self-erasure technique, mostly because I don't know how to do that  

Is there any method I can use to alter the reset vector back to FFFF ?

Hope to hear from you guys soon .....

Thanks.

F4

[peg]

Hi F4,

Your Vtst is just within spec (Vdd+2.5 to 9volts)

Once the GP is programmed you need Vtst and an external clock to get back in.

I use the methods outlined in AN-HK-32 to self erase the device on power up with a special set of inputs. This allows low voltage entry with a 32kHz xtal.

You need this added to your code though, if its not already in there it's too late now!

So as your Vtst looks OK (just) its time to check your external oscillator.