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Building a parallel port ICP adapter

Started by "leg.strong" May 11, 2008
Hi, everybody!
I am trying to build a parallel port ICP adapter. I think it will be
quite usefull and low cost.

But I can not read data from the device(LPC9107), the data line is
always high when read. What may be the problem?

To get in programming mode the RESET pin has to have a sequence of 7
pulses after the rising edge of VDD and the RST high time must between
1-32us, which is easy to achieve with today's computer. I measure the
pulse with oscilloscope, the timing falls in that range.

Anybody can help?
I get the ICP specification from this group, I will post the
documentation here when the adapter is ok.
Thanks everybody

--- In l..., "leg.strong" wrote:
>
> Hi, everybody!
> I am trying to build a parallel port ICP adapter. I think it will be
> quite usefull and low cost.
>
> But I can not read data from the device(LPC9107), the data line is
> always high when read. What may be the problem?
>
> To get in programming mode the RESET pin has to have a sequence of 7
> pulses after the rising edge of VDD and the RST high time must between
> 1-32us, which is easy to achieve with today's computer. I measure the
> pulse with oscilloscope, the timing falls in that range.
>
> Anybody can help?
> I get the ICP specification from this group, I will post the
> documentation here when the adapter is ok.
> Thanks everybody
>

I think the parallel port of the PC has pull-up resistor that can
influence the reading. Please use a bidirectional transceiver like
74hc245 to force the state of the line.


It dose have pull-up on the PDA line, because I use open-drain inverter 74HC05, connection diagram is similiar to the parallel port-iic adapter(you can find it in the linux kernel source tree\Documentation\i2c\busses\i2c-parport file), I remove the SCL read-back line and add a 74HC244 to buffer the RESET signal.


Maybe I will try 74HC245 as you mention. If the pull-up(6.2 KOhm) does cause this problem, it sounds a little strange. I doubt whether LPC9107 works


Here is the schematic(copy to text editor to make it clear):


Device                                                      PC
Side          ______________________________3.3V (+)        Side
               |    |            |    |
              ---  ---          ---  ---
              | |  |
|          | |  | |
              |R|  |R|          |R|  |R|
              | |  | |          | |  | |
              ---  ---          ---  ---
               |    |            |    |
               |    |       /|   |    |
PCL 
----------x-----------o |-------------x--------------  pin 2
                    |       \|        |    |
                    |                 |    |
                    |                 |    |
                    |      |\        
|    |
PDA  ---------------x---x--| o--------x-------------------  pin 10
                        |  |/              |
                        |                  |
                        |   /|             |
                        ---o
|------------------x---------  pin 3
                            \|             |    |
                                           |    |
                                          --- 
---
                                          | |  | |
                                          |R|  |R|
                                          | |  |
|
                                          ---  ---
                                           |    |
                                          ### 
###
                                          GND  GND
                                         
                             /|
RST  -----------------------/ |----------------------------  pin 1
                            \
|
                             \|


All resisters are 6.2KOhm

--- On Sun, 5/11/08, Stefano Panichi <g...@yahoo.it> wrote:


From: Stefano Panichi <g...@yahoo.it>
Subject: [lpc900_users] Re: Building a parallel port ICP adapter
To: l...
Date: Sunday, May 11, 2008, 8:44 AM




--- In lpc900_users@ yahoogroups. com, "leg.strong" <leg.strong@ ...> wrote:
>
> Hi, everybody!
> I am trying to build a parallel port ICP adapter. I think it will be
> quite usefull and low cost.
>
> But I can not read data from the device(LPC9107) , the data line is
> always high when read. What may be the problem?
>
> To get in programming mode the RESET pin has to have a sequence of 7
> pulses after the rising edge of VDD and the RST high time must between
> 1-32us, which is easy to achieve with today's computer. I measure the
> pulse with oscilloscope, the timing falls in that range.
>
> Anybody can help?
> I get the ICP specification from this group, I will post the
> documentation here when the adapter is ok.
> Thanks everybody
>

I think
the parallel port of the PC has pull-up resistor that can
influence the reading. Please use a bidirectional transceiver like
74hc245 to force the state of the line.





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__,_._,___
Circuit is OK. If you are sure that all timings are respected then the
CPU doesn't work.
In particular mode check that tVR time (RST delay from VDD active) is
minimum 50 usec.
Regards
--- In l..., "Stefano Panichi"
wrote:
>
> Circuit is OK. If you are sure that all timings are respected then the
> CPU doesn't work.
> In particular mode check that tVR time (RST delay from VDD active) is
> minimum 50 usec.
> Regards
>

Does anyone knows if such a circuit would also be ok for the LPC901?

In any case please report if it works, that would be interesting to know.

Cheers,

Alexandre
Hi,

it's been a while since I was dealing with the LPC900 but this is what
I remember:
ICP is possible with all LPC900 devices, including the LPC901.
IAP is not possible with the LPC901.

If I am wrong, somebody please correct me.

Bob

--- In l..., "Alexandre Pereira Nunes"
wrote:
>
> --- In l..., "Stefano Panichi"
> wrote:
> >
> > Circuit is OK. If you are sure that all timings are respected then the
> > CPU doesn't work.
> > In particular mode check that tVR time (RST delay from VDD active) is
> > minimum 50 usec.
> > Regards
> > Does anyone knows if such a circuit would also be ok for the LPC901?
>
> In any case please report if it works, that would be interesting to
know.
>
> Cheers,
>
> Alexandre
>

 
ISP Lite is possible with All LPC900..
 
Regards,

Nilesh (09925049517) 

 
 

--- On Wed, 4/6/08, lpc2100_fan <l...@yahoo.com> wrote:

From: lpc2100_fan <l...@yahoo.com>
Subject: [lpc900_users] Re: Building a parallel port ICP adapter
To: l...
Date: Wednesday, 4 June, 2008, 9:31 PM

Hi,

it's been a while since I was dealing with the LPC900 but this is what
I remember:
ICP is possible with all LPC900 devices, including the LPC901.
IAP is not possible with the LPC901.

If I am wrong, somebody please correct me.

Bob

--- In lpc900_users@ yahoogroups. com, "Alexandre Pereira Nunes"
<alexandrenunes_ 99@...> wrote:
>
> --- In lpc900_users@ yahoogroups. com, "Stefano Panichi"
> <gsembox-lpc@ > wrote:
> >
> > Circuit is OK. If you are sure that all timings are respected then the
> > CPU doesn't work.
> > In particular mode check that tVR time (RST delay from VDD active) is
> > minimum 50 usec.
> > Regards
> >
>
> Does anyone knows if such a circuit would also be ok for the LPC901?
>
> In any case please report if it works, that would be interesting to
know.
>
> Cheers,
>
> Alexandre
>

Bollywood, fun, friendship, sports and more. You name it, we have it on http://in.promos.yahoo.com/groups/bestofyahoo/
hi,
have you succeeded in resolving the output high problem. I am interested in knowing. i face similar problem with 89vx2fn. help is highly appreciated.
krishniah.
--- In l..., "Stefano Panichi" wrote:
>
> --- In l..., "leg.strong" wrote:
> >
> > Hi, everybody!
> > I am trying to build a parallel port ICP adapter. I think it will be
> > quite usefull and low cost.
> >
> > But I can not read data from the device(LPC9107), the data line is
> > always high when read. What may be the problem?
> >
> > To get in programming mode the RESET pin has to have a sequence of 7
> > pulses after the rising edge of VDD and the RST high time must between
> > 1-32us, which is easy to achieve with today's computer. I measure the
> > pulse with oscilloscope, the timing falls in that range.
> >
> > Anybody can help?
> > I get the ICP specification from this group, I will post the
> > documentation here when the adapter is ok.
> > Thanks everybody
> > I think the parallel port of the PC has pull-up resistor that can
> influence the reading. Please use a bidirectional transceiver like
> 74hc245 to force the state of the line.
>

Krishniah,

I might be wrong but I do believe that ICP for the LPC900 is rather different from the ICP for the 89V5x devices.
Did you try the NXP forum?
http://forums.nxp.com/forums/viewforum.php?f=1
It is mostly about ARM based MCUs but 51 based devices are also handled there.

Bob

--- In l..., "mv" wrote:
> hi,
> have you succeeded in resolving the output high problem. I am interested in knowing. i face similar problem with 89vx2fn. help is highly appreciated.
> krishniah.
> --- In l..., "Stefano Panichi" wrote:
> >
> > --- In l..., "leg.strong" wrote:
> > >
> > > Hi, everybody!
> > > I am trying to build a parallel port ICP adapter. I think it will be
> > > quite usefull and low cost.
> > >
> > > But I can not read data from the device(LPC9107), the data line is
> > > always high when read. What may be the problem?
> > >
> > > To get in programming mode the RESET pin has to have a sequence of 7
> > > pulses after the rising edge of VDD and the RST high time must between
> > > 1-32us, which is easy to achieve with today's computer. I measure the
> > > pulse with oscilloscope, the timing falls in that range.
> > >
> > > Anybody can help?
> > > I get the ICP specification from this group, I will post the
> > > documentation here when the adapter is ok.
> > > Thanks everybody
> > >
> >
> > I think the parallel port of the PC has pull-up resistor that can
> > influence the reading. Please use a bidirectional transceiver like
> > 74hc245 to force the state of the line.
>

Hi,

The chips i got didnt worked and i have changed the MCU to PIC.

Dani

________________________________
From: mv
To: l...
Sent: Sun, February 20, 2011 11:54:24 PM
Subject: [lpc900_users] Re: Building a parallel port ICP adapter
hi,
have you succeeded in resolving the output high problem. I am interested in
knowing. i face similar problem with 89vx2fn. help is highly appreciated.
krishniah.
--- In l..., "Stefano Panichi" wrote:
>
> --- In l..., "leg.strong" wrote:
> >
> > Hi, everybody!
> > I am trying to build a parallel port ICP adapter. I think it will be
> > quite usefull and low cost.
> >
> > But I can not read data from the device(LPC9107), the data line is
> > always high when read. What may be the problem?
> >
> > To get in programming mode the RESET pin has to have a sequence of 7
> > pulses after the rising edge of VDD and the RST high time must between
> > 1-32us, which is easy to achieve with today's computer. I measure the
> > pulse with oscilloscope, the timing falls in that range.
> >
> > Anybody can help?
> > I get the ICP specification from this group, I will post the
> > documentation here when the adapter is ok.
> > Thanks everybody
> > I think the parallel port of the PC has pull-up resistor that can
> influence the reading. Please use a bidirectional transceiver like
> 74hc245 to force the state of the line.
>



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