Reply by Anton Erasmus●November 17, 20072007-11-17
On 16 Nov 2007 at 1:07, Rahul Gaikwad wrote:
> hi everyone,
> i have designed my own lpc2138 pcb
> all the components are mounted on the pcb and are correct ,
> i also have a switch at P0.14 to put the controller board .
> but the problem is that the controller is just not going into ISP mode .
> i am using LPC2000 Flash Utility V2.2.1. by PHILIPS
> for communication purpose i have used MAX3232 and the capacitors on MAX3232
are 100nF each
>
> please guide me. what can be the problem that the controller LPC2138 is not
going into ISP mode
>
The CPU must be running to go into ISP mode. Make sure your power levels are
correct.
Make sure your crystal circuit is correct and working. The crystal must be in
the range 10MHz
to 25MHz for ISP to work. If in doubt remove the crystal and inject a clock via
a 100pF
capacitor directly into the CPU.
Regards
Anton Erasmus >
> ----- Original Message ----
> From: myn0601
> To: l...
> Sent: Friday, November 16, 2007 7:25:26 AM
> Subject: [lpc2000] Re: LPC2364 with SSD1926
>
> --- In lpc2000@yahoogroups .com, Alexandre Kremer
> wrote:
> >
> > > --- In lpc2000@yahoogroups .com, "myn0601"
> > > wrote:
> >
> > > yup, i think it is very possilbe that the 3.3v
> > > regulator can not
> > > supply enough current, as the other 2 regulator
> > > supplies 1.8v and
> > > 5.0v, their load is much lighter thant the 3.3v, and
> > > they do not have
> > > such problem. the 3.3v o/p is connected to many pins
> > > of the 2 chips.
> > >
> > >
> >
> > Is it getting really hot? If yes, this is the source
> > of your problems. Try using a switching regulator like
> > LM2576T-3.3. One of the best i know (requires extra
> > components like a diode and a coil for feedback
> > purposes), but it really works fine for all my
> > applications.
> >
> >
> >
> >
> > Abra sua conta no Yahoo! Mail, o ico sem limite de espa
> para armazenamento!
> > http://br.mail. yahoo.com/
> >
>
> can i use the LD1085#33, as this one is similar to my current
> LD1117#33 and maximal o/p current is 3A.
>
>
>
>
>
>
____________________________________________________________________________________
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>
>
>
>
It shows the JTAG and ISP connection. I wouldn't blindly copy the
design,
but at least you can look in the LPC manual and figure out what each
pull-up and pull-down resistor does in the design. I used the information
to build my own LPC2148 board for a ham radio project.
> --- In l..., Rahul Gaikwad wrote:
> >
> > hi everyone,
> > i have designed my own lpc2138 pcb
> > all the components are mounted on the pcb and are correct ,
> > i also have a switch at P0.14 to put the controller board .
> > but the problem is that the controller is just not going into ISP mode .
> > i am using LPC2000 Flash Utility V2.2.1. by PHILIPS
> > for communication purpose i have used MAX3232 and the capacitors on
> MAX3232 are 100nF each
> >
> > please guide me. what can be the problem that the controller LPC2138
> is not going into ISP mode
> >
> >
> > regards,
> > rahul gaikwad
> >
> 1. Is your clock oscillator actually running?
>
> 2. What is your indication that it is not going into ISP mode?
>
> 3. Have you used the JTAG debug interface to find out what your
> LPC2138 is actually doing after it comes out of reset?
>
> On a completely new and untested PC board there are a very large
> number of possibilities for problem locations, so a voltmeter, an
> oscilloscope, and JTAG debugger are going to be your best helpers. For
> instance, is the reset circuit actually working, are the power supply
> voltages correct, is the oscillator actually running, and if all of
> those are OK what is the ARM actually doing after reset??????
>
> --Dave
>
>
Reply by derbaier●November 16, 20072007-11-16
--- In l..., Rahul Gaikwad wrote: >
> hi everyone,
> i have designed my own lpc2138 pcb
> all the components are mounted on the pcb and are correct ,
> i also have a switch at P0.14 to put the controller board .
> but the problem is that the controller is just not going into ISP mode .
> i am using LPC2000 Flash Utility V2.2.1. by PHILIPS
> for communication purpose i have used MAX3232 and the capacitors on MAX3232 are 100nF each >
> please guide me. what can be the problem that the controller LPC2138 is not going into ISP mode > regards,
> rahul gaikwad
> 1. Is your clock oscillator actually running?
2. What is your indication that it is not going into ISP mode?
3. Have you used the JTAG debug interface to find out what your
LPC2138 is actually doing after it comes out of reset?
On a completely new and untested PC board there are a very large
number of possibilities for problem locations, so a voltmeter, an
oscilloscope, and JTAG debugger are going to be your best helpers. For
instance, is the reset circuit actually working, are the power supply
voltages correct, is the oscillator actually running, and if all of
those are OK what is the ARM actually doing after reset??????
--Dave
Reply by Rahul Gaikwad●November 16, 20072007-11-16
hi everyone,
i have designed my own lpc2138 pcb
all the components are mounted on the pcb and are correct ,
i also have a switch at P0.14 to put the controller board .
but the problem is that the controller is just not going into ISP mode .
i am using LPC2000 Flash Utility V2.2.1. by PHILIPS
for communication purpose i have used MAX3232 and the capacitors on MAX3232 are
100nF each
please guide me. what can be the problem that the controller LPC2138 is not
going into ISP mode
regards,
rahul gaikwad
----- Original Message ----
From: myn0601
To: l...
Sent: Friday, November 16, 2007 7:25:26 AM
Subject: [lpc2000] Re: LPC2364 with SSD1926
--- In lpc2000@yahoogroups .com, Alexandre Kremer
wrote: >
> > --- In lpc2000@yahoogroups .com, "myn0601"
> > wrote:
>
> > yup, i think it is very possilbe that the 3.3v
> > regulator can not
> > supply enough current, as the other 2 regulator
> > supplies 1.8v and
> > 5.0v, their load is much lighter thant the 3.3v, and
> > they do not have
> > such problem. the 3.3v o/p is connected to many pins
> > of the 2 chips.
> >
> >
>
> Is it getting really hot? If yes, this is the source
> of your problems. Try using a switching regulator like
> LM2576T-3.3. One of the best i know (requires extra
> components like a diode and a coil for feedback
> purposes), but it really works fine for all my
> applications.
>
>
>
>
> Abra sua conta no Yahoo! Mail, o ico sem limite de espa para armazenamento! > http://br.mail. yahoo.com/
>
can i use the LD1085#33, as this one is similar to my current
LD1117#33 and maximal o/p current is 3A.
