Hi all,
i check the LPC18xx user manual and see that it has 16 pins for ADC but only 8
channels in reading value. How these pins are connected to the channels?
Best regards,
Chien
![Memfault Beyond the Launch](https://d23s79tivgl8me.cloudfront.net/new2/images/temp/Memfault_Sandbox_LB.png)
Why LPC18xx has 16 pins for ADC but only 8 channels?
Started by ●August 6, 2013
Reply by ●August 6, 20132013-08-06
You need to tell us which LPC18XX you are looking at. It appears not
all LPC18XX have 16 analog input pins. For example I looked at an
LPC1810 and it has only 8 analog input channels which are shared by two
ADCs.
Howard
On 8/6/2013 3:20 AM, ntchien2013 wrote:
>
> Hi all,
>
> i check the LPC18xx user manual and see that it has 16 pins for ADC
> but only 8 channels in reading value. How these pins are connected to
> the channels?
>
> Best regards,
> Chien
[Non-text portions of this message have been removed]
all LPC18XX have 16 analog input pins. For example I looked at an
LPC1810 and it has only 8 analog input channels which are shared by two
ADCs.
Howard
On 8/6/2013 3:20 AM, ntchien2013 wrote:
>
> Hi all,
>
> i check the LPC18xx user manual and see that it has 16 pins for ADC
> but only 8 channels in reading value. How these pins are connected to
> the channels?
>
> Best regards,
> Chien
[Non-text portions of this message have been removed]
Reply by ●August 6, 20132013-08-06
Not experienced in LPC here, but ADCs, in general, can be used as single inputs
or differential (which each Channel will use two ADCs) inputs. So if you have 16
ADC inputs, either use them as non differential 16 individual inputs, or 8
differential inputs. So I expect this is the same case you are having.
--- In l..., Howard Hansen wrote:
>
> You need to tell us which LPC18XX you are looking at. It appears not
> all LPC18XX have 16 analog input pins. For example I looked at an
> LPC1810 and it has only 8 analog input channels which are shared by two
> ADCs.
>
> Howard
>
> On 8/6/2013 3:20 AM, ntchien2013 wrote:
> >
> > Hi all,
> >
> > i check the LPC18xx user manual and see that it has 16 pins for ADC
> > but only 8 channels in reading value. How these pins are connected to
> > the channels?
> >
> > Best regards,
> > Chien
> >
> > [Non-text portions of this message have been removed]
>
--- In l..., Howard Hansen wrote:
>
> You need to tell us which LPC18XX you are looking at. It appears not
> all LPC18XX have 16 analog input pins. For example I looked at an
> LPC1810 and it has only 8 analog input channels which are shared by two
> ADCs.
>
> Howard
>
> On 8/6/2013 3:20 AM, ntchien2013 wrote:
> >
> > Hi all,
> >
> > i check the LPC18xx user manual and see that it has 16 pins for ADC
> > but only 8 channels in reading value. How these pins are connected to
> > the channels?
> >
> > Best regards,
> > Chien
> >
> > [Non-text portions of this message have been removed]
>
Reply by ●August 7, 20132013-08-07
Hi Howard,
thank you for your reply. I am using mcb1800 with lpc1850 (LBGA256). I checked user manual for lpc18xx UM10430.
In the table 122 (page 279-285) I found 16 pins that has funtion ADC. However, in table 119 I found only 8 channel with corresponding pin such as: E3, C3, A4, B5, C6, B3, A5 and C5???
Do you have any idea?
Best regards,
Chien
thank you for your reply. I am using mcb1800 with lpc1850 (LBGA256). I checked user manual for lpc18xx UM10430.
In the table 122 (page 279-285) I found 16 pins that has funtion ADC. However, in table 119 I found only 8 channel with corresponding pin such as: E3, C3, A4, B5, C6, B3, A5 and C5???
Do you have any idea?
Best regards,
Chien
Reply by ●August 7, 20132013-08-07
I've just read the User Manual, and that's it. They've shared the
pins
among the two ADCs. So, in practice, you've got only 8 ADC inputs
available. There is no way of getting the 16 inputs outside the chip in a
parallel fashion.
On Wed, Aug 7, 2013 at 5:53 AM, ntchien2013 wrote:
> **
> Hi Howard,
>
> thank you for your reply. I am using mcb1800 with lpc1850 (LBGA256). I
> checked user manual for lpc18xx UM10430.
> In the table 122 (page 279-285) I found 16 pins that has funtion ADC.
> However, in table 119 I found only 8 channel with corresponding pin such
> as: E3, C3, A4, B5, C6, B3, A5 and C5???
> Do you have any idea?
> Best regards,
> Chien
>
>
>
--
Skype: felipeanl
[Non-text portions of this message have been removed]
among the two ADCs. So, in practice, you've got only 8 ADC inputs
available. There is no way of getting the 16 inputs outside the chip in a
parallel fashion.
On Wed, Aug 7, 2013 at 5:53 AM, ntchien2013 wrote:
> **
> Hi Howard,
>
> thank you for your reply. I am using mcb1800 with lpc1850 (LBGA256). I
> checked user manual for lpc18xx UM10430.
> In the table 122 (page 279-285) I found 16 pins that has funtion ADC.
> However, in table 119 I found only 8 channel with corresponding pin such
> as: E3, C3, A4, B5, C6, B3, A5 and C5???
> Do you have any idea?
> Best regards,
> Chien
>
>
>
--
Skype: felipeanl
[Non-text portions of this message have been removed]
Reply by ●August 7, 20132013-08-07
Hi Felipeanl,
I agree with what you said but still not clear about using of ADC.
For example in the lpc18xx User Manual
Channel 1 ADC:
Page 183: P4_1 coresponds to Pin A1 is ADC0_1
Page 202: PC_0 coresponds to Pin D4 is ADC1_1
Page 220: Pin C3 corespond to ADC0_1/ADC1_1 for channel 1 of ADC0/1
So in order to use ADC channel1, which pin should I connect to? In the board mcb1800 they connected to C3 but why they needs the other pin for?
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> I've just read the User Manual, and that's it. They've shared the pins
> among the two ADCs. So, in practice, you've got only 8 ADC inputs
> available. There is no way of getting the 16 inputs outside the chip in a
> parallel fashion.
>
I agree with what you said but still not clear about using of ADC.
For example in the lpc18xx User Manual
Channel 1 ADC:
Page 183: P4_1 coresponds to Pin A1 is ADC0_1
Page 202: PC_0 coresponds to Pin D4 is ADC1_1
Page 220: Pin C3 corespond to ADC0_1/ADC1_1 for channel 1 of ADC0/1
So in order to use ADC channel1, which pin should I connect to? In the board mcb1800 they connected to C3 but why they needs the other pin for?
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> I've just read the User Manual, and that's it. They've shared the pins
> among the two ADCs. So, in practice, you've got only 8 ADC inputs
> available. There is no way of getting the 16 inputs outside the chip in a
> parallel fashion.
>
Reply by ●August 7, 20132013-08-07
It is hard to understand, I still didn't get it fully yet.
But, read this at page 275:
Remark: The ADC input channels are shared between ADC0 and ADC1 on all
LPC18xx
parts. This means that input ADC0_n is connected to channel n on ADC0 and
ADC1 and
input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
Table 132.
Mapping the ADC pins we get:
P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
P4_3 ADC0_0 ( " " )
P7_4 ADC0_4 ( " " )
P7_5 ADC0_3 ( " " )
P7_7 ADC1_6 ( " " )
PB_6 ADC0_6 ( " " )
PC_0 ADC1_1 ( " " )
PC_3 ADC1_0 ( " " )
PF_5 ADC1_4 ( " " )
PF_6 ADC1_3 ( " " )
PF_7 ADC1_7 ( " " )
PF_8 ADC0_2 ( " " )
PF_9 ADC1_2 ( " " )
PF_10 ADC0_5 ( " " )
PF_11 ADC1_5 ( " " )
The truth is: In each of the above pins, you can get either ADC0 or ADC1
channel to work with.
Now, you have to check what pins are available in your LPC18xx package and
your board. This information is listed on page 1148.
On Wed, Aug 7, 2013 at 8:50 AM, ntchien2013 wrote:
> **
> Hi Felipeanl,
>
> I agree with what you said but still not clear about using of ADC.
> For example in the lpc18xx User Manual
> Channel 1 ADC:
> Page 183: P4_1 coresponds to Pin A1 is ADC0_1
> Page 202: PC_0 coresponds to Pin D4 is ADC1_1
> Page 220: Pin C3 corespond to ADC0_1/ADC1_1 for channel 1 of ADC0/1
> So in order to use ADC channel1, which pin should I connect to? In the
> board mcb1800 they connected to C3 but why they needs the other pin for?
>
> Best regards,
> Chien
> --- In l..., Felipe de Andrade Neves Lavratti
> wrote:
> >
> > I've just read the User Manual, and that's it. They've shared the pins
> > among the two ADCs. So, in practice, you've got only 8 ADC inputs
> > available. There is no way of getting the 16 inputs outside the chip in a
> > parallel fashion.
> >
>
--
Skype: felipeanl
[Non-text portions of this message have been removed]
But, read this at page 275:
Remark: The ADC input channels are shared between ADC0 and ADC1 on all
LPC18xx
parts. This means that input ADC0_n is connected to channel n on ADC0 and
ADC1 and
input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
Table 132.
Mapping the ADC pins we get:
P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
P4_3 ADC0_0 ( " " )
P7_4 ADC0_4 ( " " )
P7_5 ADC0_3 ( " " )
P7_7 ADC1_6 ( " " )
PB_6 ADC0_6 ( " " )
PC_0 ADC1_1 ( " " )
PC_3 ADC1_0 ( " " )
PF_5 ADC1_4 ( " " )
PF_6 ADC1_3 ( " " )
PF_7 ADC1_7 ( " " )
PF_8 ADC0_2 ( " " )
PF_9 ADC1_2 ( " " )
PF_10 ADC0_5 ( " " )
PF_11 ADC1_5 ( " " )
The truth is: In each of the above pins, you can get either ADC0 or ADC1
channel to work with.
Now, you have to check what pins are available in your LPC18xx package and
your board. This information is listed on page 1148.
On Wed, Aug 7, 2013 at 8:50 AM, ntchien2013 wrote:
> **
> Hi Felipeanl,
>
> I agree with what you said but still not clear about using of ADC.
> For example in the lpc18xx User Manual
> Channel 1 ADC:
> Page 183: P4_1 coresponds to Pin A1 is ADC0_1
> Page 202: PC_0 coresponds to Pin D4 is ADC1_1
> Page 220: Pin C3 corespond to ADC0_1/ADC1_1 for channel 1 of ADC0/1
> So in order to use ADC channel1, which pin should I connect to? In the
> board mcb1800 they connected to C3 but why they needs the other pin for?
>
> Best regards,
> Chien
> --- In l..., Felipe de Andrade Neves Lavratti
> wrote:
> >
> > I've just read the User Manual, and that's it. They've shared the pins
> > among the two ADCs. So, in practice, you've got only 8 ADC inputs
> > available. There is no way of getting the 16 inputs outside the chip in a
> > parallel fashion.
> >
>
--
Skype: felipeanl
[Non-text portions of this message have been removed]
Reply by ●August 7, 20132013-08-07
Hi Felipeanl,
thank you for your reply.
I do think that it should be better written and there must be a reason behind where they provide 24 pins for only 8 channels. To be in the safe side I will only use 8 channels as in the development boards. I think the chance to get support from NXP is prety low.
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> It is hard to understand, I still didn't get it fully yet.
>
> But, read this at page 275:
> Remark: The ADC input channels are shared between ADC0 and ADC1 on all
> LPC18xx
> parts. This means that input ADC0_n is connected to channel n on ADC0 and
> ADC1 and
> input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
> Table 132.
>
> Mapping the ADC pins we get:
> P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
> P4_3 ADC0_0 ( " " )
> P7_4 ADC0_4 ( " " )
> P7_5 ADC0_3 ( " " )
> P7_7 ADC1_6 ( " " )
> PB_6 ADC0_6 ( " " )
> PC_0 ADC1_1 ( " " )
> PC_3 ADC1_0 ( " " )
> PF_5 ADC1_4 ( " " )
> PF_6 ADC1_3 ( " " )
> PF_7 ADC1_7 ( " " )
> PF_8 ADC0_2 ( " " )
> PF_9 ADC1_2 ( " " )
> PF_10 ADC0_5 ( " " )
> PF_11 ADC1_5 ( " " )
>
> The truth is: In each of the above pins, you can get either ADC0 or ADC1
> channel to work with.
>
> Now, you have to check what pins are available in your LPC18xx package and
> your board. This information is listed on page 1148.
>
thank you for your reply.
I do think that it should be better written and there must be a reason behind where they provide 24 pins for only 8 channels. To be in the safe side I will only use 8 channels as in the development boards. I think the chance to get support from NXP is prety low.
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> It is hard to understand, I still didn't get it fully yet.
>
> But, read this at page 275:
> Remark: The ADC input channels are shared between ADC0 and ADC1 on all
> LPC18xx
> parts. This means that input ADC0_n is connected to channel n on ADC0 and
> ADC1 and
> input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
> Table 132.
>
> Mapping the ADC pins we get:
> P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
> P4_3 ADC0_0 ( " " )
> P7_4 ADC0_4 ( " " )
> P7_5 ADC0_3 ( " " )
> P7_7 ADC1_6 ( " " )
> PB_6 ADC0_6 ( " " )
> PC_0 ADC1_1 ( " " )
> PC_3 ADC1_0 ( " " )
> PF_5 ADC1_4 ( " " )
> PF_6 ADC1_3 ( " " )
> PF_7 ADC1_7 ( " " )
> PF_8 ADC0_2 ( " " )
> PF_9 ADC1_2 ( " " )
> PF_10 ADC0_5 ( " " )
> PF_11 ADC1_5 ( " " )
>
> The truth is: In each of the above pins, you can get either ADC0 or ADC1
> channel to work with.
>
> Now, you have to check what pins are available in your LPC18xx package and
> your board. This information is listed on page 1148.
>
Reply by ●August 7, 20132013-08-07
My dear man when doing a PCB it is good to have flexibility. In choosing the
pins all the more so in a bga package. So you have more pins to give you more
options in routing.I have not worked with the lpc18xx.The same is true for chip
selects.
Arie
Sent from Samsung Mobile
-------- Original message --------
From: ntchien2013
Date: 07/08/2013 4:41 PM (GMT+02:00)
To: l...
Subject: [lpc2000] Re: Why LPC18xx has 16 pins for ADC but only 8 channels?
Hi Felipeanl,
thank you for your reply.
I do think that it should be better written and there must be a reason behind where they provide 24 pins for only 8 channels. To be in the safe side I will only use 8 channels as in the development boards. I think the chance to get support from NXP is prety low.
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> It is hard to understand, I still didn't get it fully yet.
>
> But, read this at page 275:
> Remark: The ADC input channels are shared between ADC0 and ADC1 on all
> LPC18xx
> parts. This means that input ADC0_n is connected to channel n on ADC0 and
> ADC1 and
> input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
> Table 132.
>
> Mapping the ADC pins we get:
> P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
> P4_3 ADC0_0 ( " " )
> P7_4 ADC0_4 ( " " )
> P7_5 ADC0_3 ( " " )
> P7_7 ADC1_6 ( " " )
> PB_6 ADC0_6 ( " " )
> PC_0 ADC1_1 ( " " )
> PC_3 ADC1_0 ( " " )
> PF_5 ADC1_4 ( " " )
> PF_6 ADC1_3 ( " " )
> PF_7 ADC1_7 ( " " )
> PF_8 ADC0_2 ( " " )
> PF_9 ADC1_2 ( " " )
> PF_10 ADC0_5 ( " " )
> PF_11 ADC1_5 ( " " )
>
> The truth is: In each of the above pins, you can get either ADC0 or ADC1
> channel to work with.
>
> Now, you have to check what pins are available in your LPC18xx package and
> your board. This information is listed on page 1148.
>
[Non-text portions of this message have been removed]
Arie
Sent from Samsung Mobile
-------- Original message --------
From: ntchien2013
Date: 07/08/2013 4:41 PM (GMT+02:00)
To: l...
Subject: [lpc2000] Re: Why LPC18xx has 16 pins for ADC but only 8 channels?
Hi Felipeanl,
thank you for your reply.
I do think that it should be better written and there must be a reason behind where they provide 24 pins for only 8 channels. To be in the safe side I will only use 8 channels as in the development boards. I think the chance to get support from NXP is prety low.
Best regards,
Chien
--- In l..., Felipe de Andrade Neves Lavratti wrote:
>
> It is hard to understand, I still didn't get it fully yet.
>
> But, read this at page 275:
> Remark: The ADC input channels are shared between ADC0 and ADC1 on all
> LPC18xx
> parts. This means that input ADC0_n is connected to channel n on ADC0 and
> ADC1 and
> input ADC1_n is connected to channel n on ADC0 and ADC1, See Table 130 and
> Table 132.
>
> Mapping the ADC pins we get:
> P4_1 ADC0_1 (ADC cannel ADC0_1 and/or ADC1_1 available)
> P4_3 ADC0_0 ( " " )
> P7_4 ADC0_4 ( " " )
> P7_5 ADC0_3 ( " " )
> P7_7 ADC1_6 ( " " )
> PB_6 ADC0_6 ( " " )
> PC_0 ADC1_1 ( " " )
> PC_3 ADC1_0 ( " " )
> PF_5 ADC1_4 ( " " )
> PF_6 ADC1_3 ( " " )
> PF_7 ADC1_7 ( " " )
> PF_8 ADC0_2 ( " " )
> PF_9 ADC1_2 ( " " )
> PF_10 ADC0_5 ( " " )
> PF_11 ADC1_5 ( " " )
>
> The truth is: In each of the above pins, you can get either ADC0 or ADC1
> channel to work with.
>
> Now, you have to check what pins are available in your LPC18xx package and
> your board. This information is listed on page 1148.
>
[Non-text portions of this message have been removed]
Reply by ●August 7, 20132013-08-07
--- In l..., "ntchien2013" wrote:
>
> I think the chance to get support from NXP is prety low.
>
If you are posting your messages here NXP are unlikely to see them. They are responding to messages posted in their forums e.g.
http://www.lpcware.com/forums/microprocessor-forums/lpc18xx
Regards
Chris Burrows
--
CFB Software
http://www.astrobe.com
>
> I think the chance to get support from NXP is prety low.
>
If you are posting your messages here NXP are unlikely to see them. They are responding to messages posted in their forums e.g.
http://www.lpcware.com/forums/microprocessor-forums/lpc18xx
Regards
Chris Burrows
--
CFB Software
http://www.astrobe.com
![Memfault Beyond the Launch](https://d23s79tivgl8me.cloudfront.net/new2/images/temp/Memfault_Sandbox_LB.png)