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ICP/ISP problem in LPC922

Started by Hitesh Mahant December 26, 2005
Hi friends,

I have two types of LPC922. One lot is LPC922F CCxxxx (TSSOP), other
in LPC922FN CCxxxx. The verF is supporting multiple programming using
ISP, while verFN allows to program the chiop onlny once throught ISP.

Do you have any idea why its so?

Then I tried to implement ICP. I implemented ckt as per AN10258_2,
LPC932 in socket of MCB900 and ICPISPbridgeV1.6. it didnot worked, as
VDD was 2.65 or so, due to Vbe drop. I replaced single npn tr by npn-
pnp combo, and I got 3.15V at VDD. Then I am able to program FN chips
through ICP. But still there is a problem. 9/10 times CPU doesnot
enter ICP mode. Even its not possivle to read device-signature also.
One thing I tried, after setting time T1 & T2 1-1msec, the freq has
come to 5/10 times.

So I need to restart MCB900 & FM to get hold on it.

Can someone suggest why its happening so? And what is the solution? Or
I need to use a better and expensve programmer?

Hitesh


I've had trouble getting LPC935-936 devices into programming mode
too. What worked for me was to set the reset-output pin from the
ICPISPbridge program to push-pull in stead of weak-pull-up. Maybe
worth a try?

Gertjan --- In lpc900_users@lpc9..., "Hitesh Mahant" <vital98@e...>
wrote:
>
> Hi friends,
>
> I have two types of LPC922. One lot is LPC922F CCxxxx (TSSOP),
other
> in LPC922FN CCxxxx. The verF is supporting multiple programming
using
> ISP, while verFN allows to program the chiop onlny once throught
ISP.
>
> Do you have any idea why its so?
>
> Then I tried to implement ICP. I implemented ckt as per AN10258_2,
> LPC932 in socket of MCB900 and ICPISPbridgeV1.6. it didnot worked,
as
> VDD was 2.65 or so, due to Vbe drop. I replaced single npn tr by
npn-
> pnp combo, and I got 3.15V at VDD. Then I am able to program FN
chips
> through ICP. But still there is a problem. 9/10 times CPU doesnot
> enter ICP mode. Even its not possivle to read device-signature
also.
> One thing I tried, after setting time T1 & T2 1-1msec, the freq has
> come to 5/10 times.
>
> So I need to restart MCB900 & FM to get hold on it.
>
> Can someone suggest why its happening so? And what is the solution?
Or
> I need to use a better and expensve programmer?
>
> Hitesh
>


Message

Hello Gertjan,

Thanks for the tip. I will go through bridge code and will try to implement. I tried using 10k pullup on p0.4, p0.5 and p1.4(reset); it improved a little bit.

I am using windows98. Is it possible that is the trouble-point? Because in VB6, I have experienced that delays  below few msecs are not accurate. So CPU not getting proper RESET pulses. But in ICP that should not happen, as LPC932/935 on MCB900 generates reset pulses.

With warm regards.

Yours truly,
Hitesh Mahant
www.vital4all.com

PROGRESS of your life depends only on SIZE and QUALITY of your Goals. And the secret of success achieving them is "How discipliend YOU ARE".
Message: 6        
   Date: Mon, 26 Dec 2005 10:12:21 -0000
   From: "geejee_lpc" <y...@brui.nl>
Subject: Re: ICP/ISP problem in LPC922

I've had trouble getting LPC935-936 devices into programming mode
too. What worked for me was to set the reset-output pin from the
ICPISPbridge program to push-pull in stead of weak-pull-up. Maybe
worth a try?

Gertjan



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Gertjan,  Hitesh,

I have also had problems using ICP when following the appl.note AN10258_2.

Like you, Hitesh,  I found out that the application board VDD source is insufficient when using the npn transistor suggested in the appl.note. Once replaced with a combination of NMOS and PMOS (see link below) you get almost the full 3.3V forwarded from MCB900 to your application board. This solved the problems for me.

Schematics 

Thanks,
Maciej--- In l...@yahoogroups.com, "Hitesh Mahant" <vital98@...> wrote:
>
> Hello Gertjan,
>
> Thanks for the tip. I will go through bridge code and will try to
> implement. I tried using 10k pullup on p0.4, p0.5 and p1.4(reset); it
> improved a little bit.
>
> I am using windows98. Is it possible that is the trouble-point? Because
> in VB6, I have experienced that delays below few msecs are not
> accurate. So CPU not getting proper RESET pulses. But in ICP that should
> not happen, as LPC932/935 on MCB900 generates reset pulses.
>
> With warm regards.
>
> Yours truly,
> Hitesh Mahant
> www.vital4all.com
>
> PROGRESS of your life depends only on SIZE and QUALITY of your Goals.
> And the secret of success achieving them is "How discipliend YOU ARE".>
> Message: 6
> Date: Mon, 26 Dec 2005 10:12:21 -0000
> From: "geejee_lpc" yahoo@...
> Subject: Re: ICP/ISP problem in LPC922
>
> I've had trouble getting LPC935-936 devices into programming mode
> too. What worked for me was to set the reset-output pin from the
> ICPISPbridge program to push-pull in stead of weak-pull-up. Maybe
> worth a try?
>
> Gertjan

Memfault Beyond the Launch