Lpc2000

Hello All,
I have been using the SPI interface on a LPC2131 with good success so 
far.  Now, I am trying to interface an LCD controller (HT1621) and 
found a strange issue.  The LCD must have it's data written 12 bits
at 
a time.  So I configured the SPI control register to operate in this 
mode.

S0SPCR      =   0x0C24;

which sets 
bit#2: The SPI controller sends and receives the number of bis 
selected by bits 11:8
bit#5: Yes, I am using the LPC as a master
bits#11:10: Selects 12 bits per transfer

However, when I step thru my code, and look at the S0SPCR register,
it 
is written with a 0x0424!!!!!!!!!!!!!
For some reason bit 11 does not get written?  Consequently, this is
an 
undefined state for the register and it goes off into the wild blue 
yonder and never stops sending out clock pulses.

I am able to stop the program and manually change the register 
contents and I get the expected 12-bits shifted out.

Anybody ever experience this??  Is there a work around?

Also I am new to LCD's never programmed one before, the format of the 
data looks really strange.  If anybody knows some good tricks for 
interfacing an LCD with a serial interface, I would be grateful. 
But, 
for now I am really stuck with the problem at hand.

Thanks,
Dave B.

--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:
> Hello All,
> I have been using the SPI interface on a LPC2131 with good success 
so 
> far.  Now, I am trying to interface an LCD controller (HT1621) and 
> found a strange issue.  The LCD must have it's data written 12 bits
> at 
> a time.  So I configured the SPI control register to operate in 
this 
> mode.
> 
> S0SPCR      =   0x0C24;
> 
> which sets 
> bit#2: The SPI controller sends and receives the number of bis 
> selected by bits 11:8
> bit#5: Yes, I am using the LPC as a master
> bits#11:10: Selects 12 bits per transfer
> 
> However, when I step thru my code, and look at the S0SPCR register,
> it 
> is written with a 0x0424!!!!!!!!!!!!!
> For some reason bit 11 does not get written?  Consequently, this is
> an 
> undefined state for the register and it goes off into the wild 
blue 
> yonder and never stops sending out clock pulses.
> 
> I am able to stop the program and manually change the register 
> contents and I get the expected 12-bits shifted out.
> 
> Anybody ever experience this??  Is there a work around?
> 
> Also I am new to LCD's never programmed one before, the format of 
the 
> data looks really strange.  If anybody knows some good tricks for 
> interfacing an LCD with a serial interface, I would be grateful. 
> But, 
> for now I am really stuck with the problem at hand.
> 
> Thanks,
> Dave B.

Hi,

Use 8 bit plus 8 bit with one nibble NA, just keep CS active for two 
8-bit writes.
You have to control CS line for LCD from port pin anyhow.
Another way is to do bit banging (plenty of examples for that around)

good luck

Dave,

> So I configured the SPI control register to operate in this
> mode.
>
> S0SPCR      =   0x0C24;
> ...
> However, when I step thru my code, and look at the S0SPCR register,
> it
> is written with a 0x0424!!!!!!!!!!!!!

Strange, I tried this on my 2138 and there it all works (to say, writing 
to the register works).
Should work on the 2131 also.
I wrote a small program 
(http://www.myvoice.nl/electronics/files/io-test.zip) to read and write 
registers and memory - served me well a few times. typing "w e0020000 
c24" will write to the memory location and read it back afterwards. 
Typing "r e0020000" will read the memory. I used this program myself 
already a few times - as soon as I don't trust the hardware I start 
poking around in the chip ...

If writing to the register works, can you singlestep through the 
assembly code (that's an istep in ARM AXD) or at least see the assembly 
code and the CPU registers?

> Also I am new to LCD's never programmed one before, the format of the
> data looks really strange.  If anybody knows some good tricks for
> interfacing an LCD with a serial interface, I would be grateful.

I checked out the controller spec 
(http://mxhaard.free.fr/spca50x/Doc/LCD/1621.PDF ?) and the interface 
indeed is a bit strange compared to the I2C displays I am used to. Only 
the command mode uses 12 bits, it you write data to the LCD you should 
switch to 14 bits mode.

It should however be fairly easy, CS to a GPIO pin, WR to SCK and the 
data pin of the LCD to MOSI. Configure CPOL=1 and CPHA=1 (see 213x user 
manual), LSBF=0. This gives SOSPCR =  0x0C6E to send the commands and 
after initialization switch over to 0xE6E for 14 bits to send the first 
4 databits to a given address. Sequential datawrites should then be done 
in 8 bits mode.
This is why you should use a GPIO pin for the CS line. Sending commands 
is now like:

    CS = Low, S0SPCR = 0x0C6E, S0SPDR = cmd, wait for SPI transfer 
complete, CS = high.

Data:

    CS = Low, S0SPCR = 0xE6E, SOSPDR = addr/data, wait for SPI tr. 
compl, S0SPCR=0x86E, S0SPDR = data/data, wait, (more data), CS = High

You cannot use SSEL for the CS line, the SSEL line will go inactive 
between datatransfers.

Think I still prefer an I2C display, SPI only makes sense if you have a 
larger (graphical) display.

Good luck,

    Rob

Thanks for the good info guys.  I am looking at the assembly code 
for changing the SPI registers.  It's just a couple simple lines:

165: S0SPCR = 0x0C24;  // Changed to 12-bits per transfer for LCD 
format. 
0x0000215E  2124      MOV       R1,#0x24
0x00002160  4829      LDR       R0,[PC,#0x00A4]
0x00002162  7001      STRB      R1,[R0,#0x00]

you can see that the assembly code just puts the 0x24 in R1, the 
upper byte is gone?  Why would it do this?  I am using the memory 
and register watch windows as I step thru this code.  It is very 
clear to see that the upper byte is just ignored.  It's like the 
compiler thinks the S0SPCR register is 8-bits instead of 16. 
Ah..............
That just made me look in the LPC21xx.h file where:
#define S0SPCR         (*((volatile unsigned char *) 0xE0020000))
yes, it is defined as a char so it will only look at the first byte.
So I changed the char to short.
NO......it still does not work.????

Yes, I am using a GPIO for SEL.  That seems to work fine, I just 
can't change the size of the SPI buffer?

-Dave





--- In lpc2000@yahoogroups.com, Rob Jansen <rob@m...> wrote:
> Dave,
> 
> > So I configured the SPI control register to operate in this
> > mode.
> >
> > S0SPCR      =   0x0C24;
> > ...
> > However, when I step thru my code, and look at the S0SPCR 
register,
> > it
> > is written with a 0x0424!!!!!!!!!!!!!
> 
> Strange, I tried this on my 2138 and there it all works (to say, 
writing 
> to the register works).
> Should work on the 2131 also.
> I wrote a small program 
> (http://www.myvoice.nl/electronics/files/io-test.zip) to read and 
write 
> registers and memory - served me well a few times. typing "w 
e0020000 
> c24" will write to the memory location and read it back 
afterwards. 
> Typing "r e0020000" will read the memory. I used this program 
myself 
> already a few times - as soon as I don't trust the hardware I 
start 
> poking around in the chip ...
> 
> If writing to the register works, can you singlestep through the 
> assembly code (that's an istep in ARM AXD) or at least see the 
assembly 
> code and the CPU registers?
> 
> > Also I am new to LCD's never programmed one before, the format 
of the
> > data looks really strange.  If anybody knows some good tricks for
> > interfacing an LCD with a serial interface, I would be grateful.
> 
> I checked out the controller spec 
> (http://mxhaard.free.fr/spca50x/Doc/LCD/1621.PDF ?) and the 
interface 
> indeed is a bit strange compared to the I2C displays I am used to. 
Only 
> the command mode uses 12 bits, it you write data to the LCD you 
should 
> switch to 14 bits mode.
> 
> It should however be fairly easy, CS to a GPIO pin, WR to SCK and 
the 
> data pin of the LCD to MOSI. Configure CPOL=1 and CPHA=1 (see 213x 
user 
> manual), LSBF=0. This gives SOSPCR =  0x0C6E to send the commands 
and 
> after initialization switch over to 0xE6E for 14 bits to send the 
first 
> 4 databits to a given address. Sequential datawrites should then 
be done 
> in 8 bits mode.
> This is why you should use a GPIO pin for the CS line. Sending 
commands 
> is now like:
> 
>     CS = Low, S0SPCR = 0x0C6E, S0SPDR = cmd, wait for SPI transfer 
> complete, CS = high.
> 
> Data:
> 
>     CS = Low, S0SPCR = 0xE6E, SOSPDR = addr/data, wait for SPI tr. 
> compl, S0SPCR=0x86E, S0SPDR = data/data, wait, (more data), CS = 
High
> 
> You cannot use SSEL for the CS line, the SSEL line will go 
inactive 
> between datatransfers.
> 
> Think I still prefer an I2C display, SPI only makes sense if you 
have a 

> larger (graphical) display.
> 
> Good luck,
> 
>     Rob

Hi, I am not sire about the 2131, but the 2138 has a SPI and SSP. The
SPI only does 8 bit and the SSP allows from 4 (?) to 16 which is
programmable.

Charles

--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:

> Thanks for the good info guys.  I am looking at the assembly code 
> for changing the SPI registers.  It's just a couple simple lines:
> 
> 165: S0SPCR = 0x0C24;  // Changed to 12-bits per transfer for LCD 
> format. 
> 0x0000215E  2124      MOV       R1,#0x24
> 0x00002160  4829      LDR       R0,[PC,#0x00A4]
> 0x00002162  7001      STRB      R1,[R0,#0x00]
> 
> you can see that the assembly code just puts the 0x24 in R1, the 
> upper byte is gone?  Why would it do this?  I am using the memory 
> and register watch windows as I step thru this code.  It is very 
> clear to see that the upper byte is just ignored.  It's like the 
> compiler thinks the S0SPCR register is 8-bits instead of 16. 
> Ah..............
> That just made me look in the LPC21xx.h file where:
> #define S0SPCR         (*((volatile unsigned char *) 0xE0020000))
> yes, it is defined as a char so it will only look at the first byte.
> So I changed the char to short.
> NO......it still does not work.????
> 
> Yes, I am using a GPIO for SEL.  That seems to work fine, I just 
> can't change the size of the SPI buffer?
> 
> -Dave
> 
> 
> 
> 
> 
> --- In lpc2000@yahoogroups.com, Rob Jansen <rob@m...> wrote:
> > Dave,
> > 
> > > So I configured the SPI control register to operate in this
> > > mode.
> > >
> > > S0SPCR      =   0x0C24;
> > > ...
> > > However, when I step thru my code, and look at the S0SPCR 
> register,
> > > it
> > > is written with a 0x0424!!!!!!!!!!!!!
> > 
> > Strange, I tried this on my 2138 and there it all works (to say, 
> writing 
> > to the register works).
> > Should work on the 2131 also.
> > I wrote a small program 
> > (http://www.myvoice.nl/electronics/files/io-test.zip) to read and 
> write 
> > registers and memory - served me well a few times. typing "w 
> e0020000 
> > c24" will write to the memory location and read it back 
> afterwards. 
> > Typing "r e0020000" will read the memory. I used this program 
> myself 
> > already a few times - as soon as I don't trust the hardware I 
> start 
> > poking around in the chip ...
> > 
> > If writing to the register works, can you singlestep through the 
> > assembly code (that's an istep in ARM AXD) or at least see the 
> assembly 
> > code and the CPU registers?
> > 
> > > Also I am new to LCD's never programmed one before, the format 
> of the
> > > data looks really strange.  If anybody knows some good tricks for
> > > interfacing an LCD with a serial interface, I would be grateful.
> > 
> > I checked out the controller spec 
> > (http://mxhaard.free.fr/spca50x/Doc/LCD/1621.PDF ?) and the 
> interface 
> > indeed is a bit strange compared to the I2C displays I am used to. 
> Only 
> > the command mode uses 12 bits, it you write data to the LCD you 
> should 
> > switch to 14 bits mode.
> > 
> > It should however be fairly easy, CS to a GPIO pin, WR to SCK and 
> the 
> > data pin of the LCD to MOSI. Configure CPOL=1 and CPHA=1 (see 213x 
> user 
> > manual), LSBF=0. This gives SOSPCR =  0x0C6E to send the commands 
> and 
> > after initialization switch over to 0xE6E for 14 bits to send the 
> first 
> > 4 databits to a given address. Sequential datawrites should then 
> be done 
> > in 8 bits mode.
> > This is why you should use a GPIO pin for the CS line. Sending 
> commands 
> > is now like:
> > 
> >     CS = Low, S0SPCR = 0x0C6E, S0SPDR = cmd, wait for SPI transfer 
> > complete, CS = high.
> > 
> > Data:
> > 
> >     CS = Low, S0SPCR = 0xE6E, SOSPDR = addr/data, wait for SPI tr. 
> > compl, S0SPCR=0x86E, S0SPDR = data/data, wait, (more data), CS = 
> High
> > 
> > You cannot use SSEL for the CS line, the SSEL line will go 
> inactive 
> > between datatransfers.
> > 
> > Think I still prefer an I2C display, SPI only makes sense if you 
> have a 
> > larger (graphical) display.
> > 
> > Good luck,
> > 
> >     Rob

Charles,
If SPI only does 8-bit, why are there option bits in the Control 
Register (S0SPCR) to send and recieve 8, 9, 10,11,12,13,14,15,16 
bits of data?  The user manual pretty clearly indicates that the SPI 
is capable of this operation.
Did I miss something?  I don't see any "*" to indicate the option is 
only available on some parts of the family?

FYI, My real target processor is the LPC2141, but I am doing this 
development on the LPC2131.  According to the user manuals SPI 
description, they look identical.  
I currently have my SSP pins assigned to other functions so I can 
not use them. 
If you could please tell me where you read the SPI will only do 8-
bits, I would appreciate it.

Thanks again to everyone for the help
Dave



--- In lpc2000@yahoogroups.com, "charlesgrenz" <charles.grenz@s...> 
wrote:
> Hi, I am not sire about the 2131, but the 2138 has a SPI and SSP. 
The
> SPI only does 8 bit and the SSP allows from 4 (?) to 16 which is
> programmable.
> 
> Charles
> 
> --- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:
> > Thanks for the good info guys.  I am looking at the assembly 
code 
> > for changing the SPI registers.  It's just a couple simple lines:
> > 
> > 165: S0SPCR = 0x0C24;  // Changed to 12-bits per transfer for 
LCD 
> > format. 
> > 0x0000215E  2124      MOV       R1,#0x24
> > 0x00002160  4829      LDR       R0,[PC,#0x00A4]
> > 0x00002162  7001      STRB      R1,[R0,#0x00]
> > 
> > you can see that the assembly code just puts the 0x24 in R1, the 
> > upper byte is gone?  Why would it do this?  I am using the 
memory 
> > and register watch windows as I step thru this code.  It is very 
> > clear to see that the upper byte is just ignored.  It's like the 
> > compiler thinks the S0SPCR register is 8-bits instead of 16. 
> > Ah..............
> > That just made me look in the LPC21xx.h file where:
> > #define S0SPCR         (*((volatile unsigned char *) 0xE0020000))
> > yes, it is defined as a char so it will only look at the first 
byte.
> > So I changed the char to short.
> > NO......it still does not work.????
> > 
> > Yes, I am using a GPIO for SEL.  That seems to work fine, I just 
> > can't change the size of the SPI buffer?
> > 
> > -Dave
> > 
> > 
> > 
> > 
> > 
> > --- In lpc2000@yahoogroups.com, Rob Jansen <rob@m...> wrote:
> > > Dave,
> > > 
> > > > So I configured the SPI control register to operate in this
> > > > mode.
> > > >
> > > > S0SPCR      =   0x0C24;
> > > > ...
> > > > However, when I step thru my code, and look at the S0SPCR 
> > register,
> > > > it
> > > > is written with a 0x0424!!!!!!!!!!!!!
> > > 
> > > Strange, I tried this on my 2138 and there it all works (to 
say, 
> > writing 
> > > to the register works).
> > > Should work on the 2131 also.
> > > I wrote a small program 
> > > (http://www.myvoice.nl/electronics/files/io-test.zip) to read 
and 
> > write 
> > > registers and memory - served me well a few times. typing "w 
> > e0020000 
> > > c24" will write to the memory location and read it back 
> > afterwards. 
> > > Typing "r e0020000" will read the memory. I used this program 
> > myself 
> > > already a few times - as soon as I don't trust the hardware I 
> > start 
> > > poking around in the chip ...
> > > 
> > > If writing to the register works, can you singlestep through 
the 
> > > assembly code (that's an istep in ARM AXD) or at least see the 
> > assembly 
> > > code and the CPU registers?
> > > 
> > > > Also I am new to LCD's never programmed one before, the 
format 
> > of the
> > > > data looks really strange.  If anybody knows some good 
tricks for
> > > > interfacing an LCD with a serial interface, I would be 
grateful.
> > > 
> > > I checked out the controller spec 
> > > (http://mxhaard.free.fr/spca50x/Doc/LCD/1621.PDF ?) and the 
> > interface 
> > > indeed is a bit strange compared to the I2C displays I am used 
to. 
> > Only 
> > > the command mode uses 12 bits, it you write data to the LCD 
you 
> > should 
> > > switch to 14 bits mode.
> > > 
> > > It should however be fairly easy, CS to a GPIO pin, WR to SCK 
and 
> > the 
> > > data pin of the LCD to MOSI. Configure CPOL=1 and CPHA=1 (see 
213x 
> > user 
> > > manual), LSBF=0. This gives SOSPCR =  0x0C6E to send the 
commands 
> > and 
> > > after initialization switch over to 0xE6E for 14 bits to send 
the 
> > first 
> > > 4 databits to a given address. Sequential datawrites should 
then 
> > be done 
> > > in 8 bits mode.
> > > This is why you should use a GPIO pin for the CS line. Sending 
> > commands 
> > > is now like:
> > > 
> > >     CS = Low, S0SPCR = 0x0C6E, S0SPDR = cmd, wait for SPI 
transfer 
> > > complete, CS = high.
> > > 
> > > Data:
> > > 
> > >     CS = Low, S0SPCR = 0xE6E, SOSPDR = addr/data, wait for SPI 
tr. 
> > > compl, S0SPCR=0x86E, S0SPDR = data/data, wait, (more data), CS 
= 
> > High
> > > 
> > > You cannot use SSEL for the CS line, the SSEL line will go 
> > inactive 
> > > between datatransfers.
> > > 
> > > Think I still prefer an I2C display, SPI only makes sense if 
you 

> > have a 
> > > larger (graphical) display.
> > > 
> > > Good luck,
> > > 
> > >     Rob

Hi Dave,

It seems that S0SPCR has sprouted extra bits on the LPC213x and LPC214x. 
The CrossWorks LPC21xx header file was generated from the register 
description of an LPC2124 which doesn't have these extra bits. The next 
release of CrossWorks has header files for each LPC device to avoid 
these problems. For the time being can you modify your copy of LPC21xx.h 
from

#define S0SPSR (*(volatile unsigned char *)0xE0020004)

to

#define S0SPSR (*(volatile unsigned short *)0xE0020004)

which should help out.

Regards
Michael

>Charles,
>If SPI only does 8-bit, why are there option bits in the Control 
>Register (S0SPCR) to send and recieve 8, 9, 10,11,12,13,14,15,16 
>bits of data?  The user manual pretty clearly indicates that the SPI 
>is capable of this operation.
>Did I miss something?  I don't see any "*" to indicate the option is 
>only available on some parts of the family?
>
>FYI, My real target processor is the LPC2141, but I am doing this 
>development on the LPC2131.  According to the user manuals SPI 
>description, they look identical.  
>I currently have my SSP pins assigned to other functions so I can 
>not use them. 
>If you could please tell me where you read the SPI will only do 8-
>bits, I would appreciate it.
>
>Thanks again to everyone for the help
>Dave
>
>
>
>--- In lpc2000@yahoogroups.com, "charlesgrenz" <charles.grenz@s...> 
>wrote:
>  
>
>>Hi, I am not sire about the 2131, but the 2138 has a SPI and SSP. 
>>    
>>
>The
>  
>
>>SPI only does 8 bit and the SSP allows from 4 (?) to 16 which is
>>programmable.
>>
>>Charles
>>
>>--- In lpc2000@yahoogroups.com, "drb5599" <dbutler@c...> wrote:
>>    
>>
>>>Thanks for the good info guys.  I am looking at the assembly 
>>>      
>>>
>code 
>  
>
>>>for changing the SPI registers.  It's just a couple simple lines:
>>>
>>>165: S0SPCR = 0x0C24;  // Changed to 12-bits per transfer for 
>>>      
>>>
>LCD 
>  
>
>>>format. 
>>>0x0000215E  2124      MOV       R1,#0x24
>>>0x00002160  4829      LDR       R0,[PC,#0x00A4]
>>>0x00002162  7001      STRB      R1,[R0,#0x00]
>>>
>>>you can see that the assembly code just puts the 0x24 in R1, the 
>>>upper byte is gone?  Why would it do this?  I am using the 
>>>      
>>>
>memory 
>  
>
>>>and register watch windows as I step thru this code.  It is very 
>>>clear to see that the upper byte is just ignored.  It's like the 
>>>compiler thinks the S0SPCR register is 8-bits instead of 16. 
>>>Ah..............
>>>That just made me look in the LPC21xx.h file where:
>>>#define S0SPCR         (*((volatile unsigned char *) 0xE0020000))
>>>yes, it is defined as a char so it will only look at the first 
>>>      
>>>
>byte.
>  
>
>>>So I changed the char to short.
>>>NO......it still does not work.????
>>>
>>>Yes, I am using a GPIO for SEL.  That seems to work fine, I just 
>>>can't change the size of the SPI buffer?
>>>
>>>-Dave
>>>
>>>
>>>
>>>
>>>
>>>--- In lpc2000@yahoogroups.com, Rob Jansen <rob@m...> wrote:
>>>      
>>>
>>>>Dave,
>>>>
>>>>        
>>>>
>>>>>So I configured the SPI control register to operate in this
>>>>>mode.
>>>>>
>>>>>S0SPCR      =   0x0C24;
>>>>>...
>>>>>However, when I step thru my code, and look at the S0SPCR 
>>>>>          
>>>>>
>>>register,
>>>      
>>>
>>>>>it
>>>>>is written with a 0x0424!!!!!!!!!!!!!
>>>>>          
>>>>>
>>>>Strange, I tried this on my 2138 and there it all works (to 
>>>>        
>>>>
>say, 
>  
>
>>>writing 
>>>      
>>>
>>>>to the register works).
>>>>Should work on the 2131 also.
>>>>I wrote a small program 
>>>>(http://www.myvoice.nl/electronics/files/io-test.zip) to read 
>>>>        
>>>>
>and 
>  
>
>>>write 
>>>      
>>>
>>>>registers and memory - served me well a few times. typing "w 
>>>>        
>>>>
>>>e0020000 
>>>      
>>>
>>>>c24" will write to the memory location and read it back 
>>>>        
>>>>
>>>afterwards. 
>>>      
>>>
>>>>Typing "r e0020000" will read the memory. I used this program 
>>>>        
>>>>
>>>myself 
>>>      
>>>
>>>>already a few times - as soon as I don't trust the hardware I 
>>>>        
>>>>
>>>start 
>>>      
>>>
>>>>poking around in the chip ...
>>>>
>>>>If writing to the register works, can you singlestep through 
>>>>        
>>>>
>the 
>  
>
>>>>assembly code (that's an istep in ARM AXD) or at least see the 
>>>>        
>>>>
>>>assembly 
>>>      
>>>
>>>>code and the CPU registers?
>>>>
>>>>        
>>>>
>>>>>Also I am new to LCD's never programmed one before, the 
>>>>>          
>>>>>
>format 
>  
>
>>>of the
>>>      
>>>
>>>>>data looks really strange.  If anybody knows some good 
>>>>>          
>>>>>
>tricks for
>  
>
>>>>>interfacing an LCD with a serial interface, I would be 
>>>>>          
>>>>>
>grateful.
>  
>
>>>>I checked out the controller spec 
>>>>(http://mxhaard.free.fr/spca50x/Doc/LCD/1621.PDF ?) and the 
>>>>        
>>>>
>>>interface 
>>>      
>>>
>>>>indeed is a bit strange compared to the I2C displays I am used 
>>>>        
>>>>
>to. 
>  
>
>>>Only 
>>>      
>>>
>>>>the command mode uses 12 bits, it you write data to the LCD 
>>>>        
>>>>
>you 
>  
>
>>>should 
>>>      
>>>
>>>>switch to 14 bits mode.
>>>>
>>>>It should however be fairly easy, CS to a GPIO pin, WR to SCK 
>>>>        
>>>>
>and 
>  
>
>>>the 
>>>      
>>>
>>>>data pin of the LCD to MOSI. Configure CPOL=1 and CPHA=1 (see 
>>>>        
>>>>
>213x 
>  
>
>>>user 
>>>      
>>>
>>>>manual), LSBF=0. This gives SOSPCR =  0x0C6E to send the 
>>>>        
>>>>
>commands 
>  
>
>>>and 
>>>      
>>>
>>>>after initialization switch over to 0xE6E for 14 bits to send 
>>>>        
>>>>
>the 
>  
>
>>>first 
>>>      
>>>
>>>>4 databits to a given address. Sequential datawrites should 
>>>>        
>>>>
>then 
>  
>
>>>be done 
>>>      
>>>
>>>>in 8 bits mode.
>>>>This is why you should use a GPIO pin for the CS line. Sending 
>>>>        
>>>>
>>>commands 
>>>      
>>>
>>>>is now like:
>>>>
>>>>    CS = Low, S0SPCR = 0x0C6E, S0SPDR = cmd, wait for SPI 
>>>>        
>>>>
>transfer 
>  
>
>>>>complete, CS = high.
>>>>
>>>>Data:
>>>>
>>>>    CS = Low, S0SPCR = 0xE6E, SOSPDR = addr/data, wait for SPI 
>>>>        
>>>>
>tr. 
>  
>
>>>>compl, S0SPCR=0x86E, S0SPDR = data/data, wait, (more data), CS 
>>>>        
>>>>
>= 
>  
>
>>>High
>>>      
>>>
>>>>You cannot use SSEL for the CS line, the SSEL line will go 
>>>>        
>>>>
>>>inactive 
>>>      
>>>
>>>>between datatransfers.
>>>>
>>>>Think I still prefer an I2C display, SPI only makes sense if 
>>>>        
>>>>
>you 
>  
>
>>>have a 
>>>      
>>>
>>>>larger (graphical) display.
>>>>
>>>>Good luck,
>>>>
>>>>    Rob
>>>>        
>>>>
>
>
>
>
>
> 
>Yahoo! Groups Links
>
>
>
> 
>
>
>  
>

Dave,

> Did I miss something?  I don't see any "*" to indicate the option is
> only available on some parts of the family?
>
> FYI, My real target processor is the LPC2141, but I am doing this
> development on the LPC2131.  According to the user manuals SPI
> description, they look identical. 
>
Both should work in 9..16 bits mode.
I tried writing the register on my 2138 board and that went OK.

The LPC2104/5/6 only support 8 bits (that's why the register was defined 
as 8 bits in your lpc21xx.h file).
If you still suspect your program try my io-test program 
(http://www.myvoice.nl/electronics/files/io-test.zip) it writes and 
reads memory in 32-bits read and write mode.

Rob