An interface between Matlab and the CED-1401.

"Matced" is an interface that allows Matlab to directly control the CED-1401 data acquisition system. This allows one to have a powerful front-end computing environment to process and plot data sampled by the CED. At the same time one can program the CED-1401 using Matlab's M-files. Together with Matlab's graphical user interface (uicontrol) one can easily build a complete windows application using M-files.

The interface is very simple to use. The matced.dll file is a 16-bit dynamic loadable library that allows Matlab to have access to the commands in the CED. The calls to the different CED functions is mediated by the matced() function. The basic call to this function has the format:

output = matced('CED_COMMAND_STRING', [parameters]);

For example, the line
matced('cedOpen');
will open the CED box while something like

r = matced('cedFrom',1000,0);
will return in the variable r a vector of length 1000 containing the values of the first 1000 words in the CED users' memory space.

All you have to do to be able to use it is to download the matced.dll file and place in somewhere where matlab can find it (you may want to modify your MATLABPATH environment variable to do this). You also need to do the same with the use1401.dll file.

List of All the Commands:

---

matced('cedOpen');
It will open the CED and will display a message on the Matlab console specifying if the command was successful or if it failed (with the appropriate error code).

---

matced('cedClose');
It will close the CED and display a message on the Matlab console specifying if the command was successful or if it failed (with the appropriate error code).

---

matced('cedReset');
It will reset the CED and display a message on the Matlab console specifying if the command was successful or if it failed (with the appropriate error code).

---

matced('cedTo1401',size,start,X);
It will transfer the data in the vector X to the memory in the CED with starting address 'start' and length of 'size' words. The floating point elements in X must be within the limits of the 12bit precision in the CED (this is your job to check!) The maximum size of a vector that can be transfer in one call is 4000. Therefore, to transfer longer vectors a number of calls is necessary. A simple Matlab M-file to do this is the following:

function cedTo(size,start,r)
%% cedTo                Transfer data to 1401.
%%                      cedTo(length,start,array)

if(size>4000)			%% should we split the data?
l = fix(size/4000);
rest = rem(size,4000);
for(i=0:l)			%% send data in 4000 blocks...
  if(i~=l)
    len = 4000;
  else
    len = rest;			%% send the last piece...
  end
  addr = start+2*4000*i;
  from = 1+4000*i;
  to = from+len-1;
  matced('cedTo1401',len,addr,r(from:to));
end
else				%% we can do it in one call...
  matced('cedTo1401',size,start,r);
end

---

r = matced('cedToHost',size,start);
As you guessed this will transfer an array of length 'size' words (2*size bytes) starting at address 'start'. The result is stored in the matlab array 'r'. Again, the maximum length of the array is 4000. If you need to tranfer longer arrays you need to write a small M-file as the one above for 'cedTo1401'.

---

matced('cedLd','cmmd1', ... 'cmmdN'));
You use this line to load commands into the CED. Each command string is the name of one 1401 command. For example, matced('cedLd','MEMDAC','ADCMEM'); will load the MEMDAC and adcmem commands. If the command fails it returns an index into the string that caused the problem (in the above example an index of 1 would mean that trying to load MEMDAC caused the error).

---

matced('cedSendString','command')
Send the string 'command' to the CED. This is what one uses to execute commands on the CED. For example, a matlab sequence like:

cmd = sprintf('ADCMEM,I,2,200000,2000,%d,1,CT,10,10;',in);
matced('cedSendString',cmd);

is setting up a command string 'cmd' with an ADCMEM command and sending it to the CED.

---

s = matced('cedGetString')
Get a string from the CED. For example, a useful M-file that I have to check for errors in the CED is the following:

function err = cedErr
%% cedErr               Get the CED error codes

matced('cedSendSTring','ERR;');
s = matced('cedGetString');
[a,b]= strtok(s);
err1 = str2num(a);
err2 = str2num(b);
err = [err1 err2];

This cedErr matlab function will return a 2-dimensional vector err with the values of e1 and e2. If there is nothing to read in the buffer the function will return with a timeout.

---

s = matced('cedGetUserMemorySize');
Returns in the variable s the size (in bytes) of the user memory space.

---

matced('cedStateOf1401');
Prints a message displaying the state of the 1401.

---

s = matced('cedStat1401');
This returns the code that one obtains by calling the U14Stat1401(0) function.

---

r = matced('cedGetTimeOut');
It returns in r the value of the current timeout setting (usually 180).

---

matced('cedSetTimeOut',value);
It sets the timeout to 'value'.

---