Init unsigned char array with string values

MIOS programming (C)
1

Hi people,

My user-project is a midi controller with 17 sensors, each of which has a 16 letters name (2 blocs of 8 characters)

and the user can change the name at any moment by moving a data wheel on any letter.

Here is the way the arrays are declared :

unsigned char CTL_NAME_PART1[17][9]; // the ninth character is for \0
unsigned char CTL_NAME_PART2[17][9];

Today these arrays are initialized byte after byte from the content of the bankstick. But I’m not very satisfied with a solution that relies on the content of the bankstick. I want to find a way to initialize the arrays, and I want to avoid doing it letter by letter. The problem is when I try this :

CTL_NAME_PART1[0] = "Whatever string";

I get a “cannot assign values to aggregates” error … any idea ?

I already tried other solutions, some of them telling me I hadn’t enough memory to do this … is it bad news ?

Is there a real risk to rely on the content of the bankstick ? For instance, what happens if the bankstick module itself gets unplugged ? Is all the data lost ?

Thanks for your help !

Olivier

2

Well firstly that string’s too long :wink: Although maybe that’s not the problem, it doesn’t help that we aren’t looking at real code… I can see a few reasons that might not work…

Just to demonstrate why it’s important to show the real code, when I tried what you said,

unsigned char CTL_NAME_PART1[17][9]; // the ninth character is for \0


CTL_NAME_PART1[0]= "whatever";

I got this:

main.c:74: error 47: indirections to different types assignment   
from type 'const-char code-[9] '
to type 'unsigned-char'

Which is expected because I’m trying to assign the string from codespace to ram. You need to use memcpy or similar for that. (Note that the last time I tried memcpy it didn’t work and I didn’t try ito fix it yet) In order to get the error you referred to, I had to do this:

unsigned char mytest[9]={"Whatever"};

CTL_NAME_PART1[0] = mytest[0];

So… do like my sig, and copy and paste, please!

The memory errors may or may not be problematic, uhm… can you copy and paste for us :wink:

3

Hi Olivier,

Today these arrays are initialized byte after byte from the content of the bankstick. But I’m not very satisfied with a solution that relies on the content of the bankstick. I want to find a way to initialize the arrays’ date=’ and I want to avoid doing it letter by letter.[/quote’]

why don’t you use the EEPROM for additionally storing the last loaded/saved or initial patch? There should be enough space to store 17 strings…

I don’t know why you think it’s so bad to read it char by char. The best other approach I can imagine would be to read the whole 64 byte page, but I don’t see how that could fit into your 17 * 17 * 9 pattern.

Cheers,

Michael

4

Hey guys thanks for showing up  ;D

EEPROM would have been great solution but 17*16=272 bytes … bit too much  :frowning: (256 available)

I did the test to totally unplug the bankstick module & replug it; of course everything’s still there  :-[ I was a fool to have doubts about this …

I’ll go for the simplier BankStick way of storing my names. I got 8 sticks so I’ll dedicate 7 for the presets (with the FFU fiels I can store 64 presets per module, that gives 7*64=448 presets which is already way too much  8)

The end is near !  ;D :slight_smile:

Thanks guys