mb808
Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
mb808 [2006/08/30 04:09] moogah |
mb808 [2011/09/13 12:34] (current) gslug Removed Spam |
||
|---|---|---|---|
| Line 14: | Line 14: | ||
| - | This application is not meant to be part of a modular system or even a standalone box, it's origins are a simple adaptation of the MBSEQ v2.4 application to mimic to functionality of the original 808's digital section. As such the primary task for this application is to provide 13 editable tracks to cover the 12 instruments + accent data and to create the proper pulse signals for the inputs of the instruments. However, MBSEQ v2.4 is a very deep application and it would be a shame to ignore many it's features so the primary task is to create an interface using the available buttons and encoders that can access as many menu functions as possible, without making the whole thing obscure. Remember, this is a drummachine first, sequencer second :) | + | This application is not meant to be part of a modular system or even a standalone box, it's origins are a simple adaptation of the MBSEQ v2.4 application to mimic to functionality of the original 808's digital section. As such the primary task for this application is to provide 13 editable tracks to cover the 12 instruments + accent data and to create the proper pulse signals for the inputs of the instruments. However, MBSEQ v2.4 is a very deep application and it would be a shame to ignore many it's features so the secondary task is to create an interface using the available buttons and encoders that can access as many menu functions as possible, without making the whole thing obscure. Remember, this is a drummachine first, sequencer second :) |
| ==== Features ==== | ==== Features ==== | ||
| Line 28: | Line 28: | ||
| * Each pattern will have A and B variations that can be switched between or morphed between with dedicated controlls | * Each pattern will have A and B variations that can be switched between or morphed between with dedicated controlls | ||
| * Save, Copy, Paste and Clear operations. One level of undo would be sweet. | * Save, Copy, Paste and Clear operations. One level of undo would be sweet. | ||
| + | * Dedicated tempo encoder | ||
| + | * Dedicated tap tempo button | ||
| ==== Theory of operation ==== | ==== Theory of operation ==== | ||
| - | The MB808 application will essentially be unchanged from the SEQ v2.4 application. The changes that will be made reguard the interface, specifically the LCD screen and encoders will not be present. At this time I also think it is best to use TK's drummode for the operation of the sequencer. Although this prevents each step from having it's own flam value, what we gain is much more than what we loose. Firstly using drum mode gives us 12 instrument tracks + accent all in one pattern as opposed to re-working the handling of the pattern sets to allow the use of 12 complete tracks, this keeps things compatible with the base application and hopefully with the upcoming SEQv3 application :) Using drum mode also allows us to use the morph feature, but in a way that mimics the original 808. Each pattern can be linked to the same pattern in the lowercase bank switched between like with the "A+B" toggle switch on the original, my favorite feature. This will take a bit of trickery in code to keep things compatible, so it may not be implemented in the first version. The second big advantage I realized this morning while thinking about the Pro-1. It's sequencer was absolutely minimal, you just switched into edit mode and entered notes until the phrase was entered. No rests. The Pro-1 would then play it back, automatically looping it. I realized that with the extra tracks avaiable and using the arrpegiate mode along with the step edit mode the mb808 could also sequence basslines and trigger arrpegios! This is very cool! | + | The MB808 application will essentially be unchanged from the SEQ v2.4 application and I hope to create an adaptation of the V3 which keeps all the best features for a drum sequencer. The changes that will be made reguard the interface, specifically the LCD screen and encoders will not be present by default, but will still be supported in software. At this time I also think it is best to use TK's drummode for the operation of the sequencer. Although this prevents each step from having it's own flam value, what we gain is much more than what we lose. Firstly using drum mode gives us 12 instrument tracks + accent all in one pattern as opposed to re-working the handling of the pattern sets to allow the use of 12 complete tracks, this keeps things compatible with the base application and hopefully with the upcoming SEQv3 application :) Using drum mode also allows us to use the morph feature, but in a way that mimics the original 808, where each pattern had A and B variations that could be chained together. Instead of accessing 16 banks of 8 patterns the interface and some of the functionality will be modified so that there are only 8 banks of 8 patterns, the remaining 8 banks will become the "B" variations for those patterns. This will take a bit of trickery in code to keep things compatible, so it may not be implemented in the first version. The GP buttons will retain their default function for each mode, but will gain additional functionality through the use of 4 extra menu shortcut buttons (F1-F4) which will allow the user to select a menu, set the cursor position and enter a value without needing a screen. Accessing the 4 additional menus is a matter of holding one of the menu keys down, at which point the 16 GP Led's will display information about the menu page and paramters represented. Once a parameter has been entered the menu can be automatically exited, or the application could simply wait until the menu key has been released. The Select and Exit buttons are still present on the layout, but at this time it is a bit unclear what their function will be. The metronome feature will not be so readily accessable and will instead be replaced by a dedicated button for tap tempo. A dedicated tempo encoder will also be included. |
| ==== Description of the interface ==== | ==== Description of the interface ==== | ||
| Line 130: | Line 132: | ||
| * SEQ_GP_Button then checks to see if a "callback hook" has been installed. I am not 100% clear on the function of the callback hook, when and why it is installed, but if it is not installed the application will end up branching to either Step edit mode or song mode. | * SEQ_GP_Button then checks to see if a "callback hook" has been installed. I am not 100% clear on the function of the callback hook, when and why it is installed, but if it is not installed the application will end up branching to either Step edit mode or song mode. | ||
| * If the hook has been installed than the application branches to CS_MENU_ExecMenuGPCallbackHook [502] | * If the hook has been installed than the application branches to CS_MENU_ExecMenuGPCallbackHook [502] | ||
| - | * Once the application has branched to this point it begins dealing with the minutia of navigating the menu and handling the LCD. Since there are many technical considerations to these processes which will not be immediatly obvious the program flow will be difficult to read, so we are going to start with a higher level analysis of how the menus are mapped and how parameters are accessed, edited and stored. Once we understand that we can isolate the functions we are most interested in. | + | * Once the application has branched to this point it begins dealing with the minutia of navigating the menu and handling the LCD. Since there are many technical considerations to these processes which will not be immediatly obvious we are going to start with a higher level analysis of how the menus are mapped and how parameters are accessed, edited and stored. Once we understand that we can isolate the functions we are most interested in. |
| * The menus are implemented through a table of function pointers that are retrived through an index which is determined by the context of the mode and GP button number. You can see the menu tables in cs_menu_tables.inc | * The menus are implemented through a table of function pointers that are retrived through an index which is determined by the context of the mode and GP button number. You can see the menu tables in cs_menu_tables.inc | ||
| Spend some time reading that file until you get a grasp of it's premise. Menus are created and navigated by indexing through a matrix of function pointers. Take note of some parameters from cs_menu.inc: | Spend some time reading that file until you get a grasp of it's premise. Menus are created and navigated by indexing through a matrix of function pointers. Take note of some parameters from cs_menu.inc: | ||
| * CS_MENU_CURSOR_POS | * CS_MENU_CURSOR_POS | ||
| + | * CS_MENU_POS | ||
| + | * CS_MENU_NEW_POS | ||
| + | * CS_MENU_ENTRIES | ||
| + | * CS_STAT | ||
| Let's allow that to sink in for awhile. | Let's allow that to sink in for awhile. | ||
| * Next we want to know how parameters are modified. From the operation of the SEQ we know that the navigation functions (Right, Left, Datawheel, Select, Exit) are used to select a parameter within a menu and then the Datawheel and Right/Left buttons can increment it's value. Browsing through cs_menu.inc we can find the following three functions which sum up these operations: | * Next we want to know how parameters are modified. From the operation of the SEQ we know that the navigation functions (Right, Left, Datawheel, Select, Exit) are used to select a parameter within a menu and then the Datawheel and Right/Left buttons can increment it's value. Browsing through cs_menu.inc we can find the following three functions which sum up these operations: | ||
| Line 148: | Line 154: | ||
| ;; branches to menu parameter hook and requests screen update | ;; branches to menu parameter hook and requests screen update | ||
| ;; --------------------------------------------------------------------------'' | ;; --------------------------------------------------------------------------'' | ||
| + | |||
mb808.1156910985.txt.gz ยท Last modified: 2006/10/15 09:35 (external edit)
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 4.0 International
