RISC DISC 2

home *** CD-ROM | disk | FTP | other *** search

/ RISC DISC 2 / RISC_DISC_2.iso / pd_share / program / language / motasm / examples_hc11_as11_SYSTEM < prev next >

Wrap

Text File | 1995-05-13 | 23.4 KB | 410 lines

*SYSTEM.AS * ******************************************************************************* * * * SYSTEM CONFIGURATION * * * * This information must be entered by the user to define the configuration of * * the system. These equates are used to define the extents of the MCX11 * * system tables. THIS FILE MUST BE THE FILE NAMED IN THE ASSEMBLY COMMAND * * LINE. It may be named anything the user wishes. Remember that AS11 names * * S-Record object file after the first file name encountered in the assembly * * command. * * * ******************************************************************************* * * * APPLICATION EQUATES * * (These VALUES should be changed for your application where indicated) * * * * DO NOT CHANGE THE SYMBOL NAMES BECAUSE THEY ARE USED THROUGHOUT MCX11 * * * ******************************************************************************* ******************************************************************************* * BASIC CONFIGURATION DATA EQUATES * * These should change for your application * ******************************************************************************* NTASKS equ 5 Number of tasks in system NQUEUES equ 2 Number of queues in system NNAMSEM equ 8 Number of named semaphores in system NTIMERS equ 3 Number of timers in system ******************************************************************************* * SYSTEM MEMORY EQUATES * * These should change for your application * ******************************************************************************* MCXVAR equ $EF Base RAM address of MCX variables (17 bytes * are needed. For example, $ef - $ff) MCX11 equ $E000 Base ROM address for MCX11 MCXTABL equ MCXVAR-1 Base RAM address of MCX system tables ******************************************************************************* * CLOCK AND PRESET EQUATES * * These should change for your application * ******************************************************************************* TMSK2 equ $1024 TFLG2 equ TMSK2+1 PACTL equ TFLG2+1 RTII equ $40 RTI Interrupt enabled, prescale = 00 RTR equ $02 16.37 ms per TICK @ 8MHz RTIF equ $40 TOCK equ 3 3 TICKs per TOCK (TOCK = 49.14 ms ~ 20 Hz) ******************************************************************************* * MCX11 EQUATES * * (These should not be changed) * ******************************************************************************* TCBLEN equ 5 Length of a Task Control Block TIMRLEN equ 8 Length of a Timer Block QHDRLEN equ 3 Length of a Queue Header ******************************************************************************* * SYSTEM TABLE EQUATES * * (These should not be changed) * ******************************************************************************* NT equ NTIMERS*TIMRLEN TIMERS equ MCXTABL-NT Base address of timer blocks NQ equ NQUEUES*QHDRLEN QHDRTBL equ TIMERS-NQ Base address of queue headers NQS equ NQUEUES*2 FLGTBL equ QHDRTBL-NNAMSEM-NTASKS-NQS Base address of semaphores NTS equ NTASKS*TCBLEN STATLS equ FLGTBL-NTS-TCBLEN Base address of Task Control Blocks (TCB) QBODBAS equ STATLS-1 Last address of Queue Bodies ******************************************************************************* * TCB INITIALIZATION DATA BLOCK EQUATES * * (These should not be changed) * ******************************************************************************* INITST equ 0 Task STATE at system initialization STRTADR equ 1 Task starting address RSTSP equ 3 *Base address of task@@s stack TCBADDR equ 5 Address of task@@s TCB TCBDATL equ 7 Length of a TCB initialization data block ******************************************************************************* * QUEUE INITIALIZATION DATA BLOCK EQUATES * * (These should not be changed) * ******************************************************************************* WIDTH equ 0 Width of the queue entry DEPTH equ 1 Depth of queue (# of entries) QHADR equ 2 Queue Header address QADDR equ 4 Address of the Queue Body QUEDATL equ 6 Length of a Queue initialization data block ******************************************************************************* * MCX ESR equates * ******************************************************************************* .wait. equ 1 Wait for an event to occur .signal. equ 2 Signal the occurence of an event .pend. equ 3 Set a semaphore to PENDing state .send. equ 4 Send a message to a task .sendw. equ 5 Send a message and wait for response .receive. equ 6 Receive a message .deque. equ 7 Dequeue an entery from a FIFO queue .enque. equ 8 Enqueue an entry into a FIFO queue .resume. equ 9 Resume a suspended task .suspend. equ 10 Suspend a task .terminate. equ 11 Terminate a task .execute. equ 12 Execute a task .delay. equ 13 Delay a task for a period of time .timer. equ 14 Set up a timer .purge. equ 15 Purge active timer(s) ******************************************************************************* * * * TASK AND QUEUE INITIALIZATION DATA BLOCKS * * These should change for your application * * * * The next section contains the initialization data blocks for the TCB@@s and * * the queues. The user should construct these tables as they define such data * * as queue sizes, task starting addresses, and stack sizes. * * * ******************************************************************************* ******************************************************************************* * QUEUE INITIALIZATION DATA BLOCKS * * These must be in ROM * * (Do Queue definitions before Task definitions) * ******************************************************************************* ORG MCX11 QUEDATA equ * Queue data (This must come first) ******************************************************************************* * THESE ARE LOCAL SYMBOLS AND CAN BE CHANGED * ******************************************************************************* Q1W equ 1 Queue 1 width Q1D equ 8 Queue 1 depth Q1SIZ equ Q1W*Q1D Queue 1 size Q1BODY equ QBODBAS-Q1SIZ+1 Address of Queue 1 body Q1HDR equ QHDRTBL Address of Queue 1 Header FCB Q1W,Q1D WIDTH,DEPTH FDB Q1HDR,Q1BODY QHADR,QADDR Q2W equ 5 Queue 2 width Q2D equ 1 Queue 2 depth Q2SIZ equ Q2W*Q2D Queue 2 size Q2BODY equ Q1BODY-Q2SIZ Address of Queue 2 body Q2HDR equ Q1HDR+QHDRLEN Address of Queue 1 Header FCB Q2W,Q2D WIDTH,DEPTH FDB Q2HDR,Q2BODY QHADR,QADDR ******************************************************************************* STKBASE equ Q2BODY-1 Base address of all stacks. This is defined * as the address of the last queue body - 1. ******************************************************************************* ******************************************************************************* * TASK INITIALIZATION DATA BLOCKS * * * * (Do Task Definitions after Queue definitions) * ******************************************************************************* TCBDATA equ * Task data ******************************************************************************* * THESE ARE LOCAL SYMBOLS AND CAN BE CHANGED * ******************************************************************************* * You must define certain information about the tasks in your application. * * The information MUST be supplied in the following sequence: * * * * 1. Initial status of the task at Power-up * * 2. The starting address of the task * * 3. The base address of the stack for the task * * 4. The TCB address of the task (This is redundant but it saves time) * * * * The TCB address, the base address of the stack, and the stack size can be * * defined through equates and used in the definitions. REMEMBER, If you are * * using an HC11 EVB, you must make the stack size for each task AT LEAST 18 * * bytes to accomodate the breakpoint mechanism. * * * * --- N O T E --- * * * * In normal usage, MCX will have the clock driver as task number 1. That * * it the highest priority task in the system and assures the best timing. You * * may change it to another if you wish, but it may not provide accurate time * * measurement if it can be preempted by another task. It is strongly urged * * that you always make task 1 the clock driver if your application is to use * * a time base. * ******************************************************************************* TASK1 equ STATLS Task1 TCB address (Task 1 = CLOCK DRIVER) STAK1 equ STKBASE Base address of task 1 stack STK1SIZ equ 18 Size of stack for task 1 FCB 0 INITST is RUN FDB clkdrv,STAK1,TASK1 STRTADR,RSTSP,TCBADDR TASK2 equ TASK1+TCBLEN Task 2 TCB address STAK2 equ STAK1-STK1SIZ Base address of task 2 stack STK2SIZ equ 23 Size of stack for task 2 FCB 0 INITST is RUN FDB $0002,STAK2,TASK2 STRTADR,RSTSP,TCBADDR TASK3 equ TASK2+TCBLEN Task 3 TCB address STAK3 equ STAK2-STK2SIZ Base address of task 3 stack STK3SIZ equ 21 Stack size for task 3 FCB _IDLE INITST FDB $0003,STAK3,TASK3 STRTADR,RSTSP,TCBADDR TASK4 equ TASK3+TCBLEN Task 4 TCB address STAK4 equ STAK3-STK3SIZ Base address of task 4 stack STK4SIZ equ 18 Stack size for task 4 FCB _IDLE INITST FDB $0004,STAK4,TASK4 STRTADR,RSTSP,TCBADDR TASK5 equ TASK4+TCBLEN Task 5 TCB address STAK5 equ STAK4-STK4SIZ Base address of task 5 stack STK5SIZ equ 18 Stack size for task 5 FCB _IDLE INITST FDB $0005,STAK5,TASK5 STRTADR,RSTSP,TCBADDR ******************************************************************************* * Now that the tasks are all defined, all that is left is the definition of * * the base address of the system stack. It should be located 18 bytes below * * the top of the stack area for the last task defined above. The 18 bytes are * * there for the stack for the null task. * ******************************************************************************* SYSTACK equ STAK5-STK5SIZ-18 Base address of system stack. ******************************************************************************* ******************************************************************************* ******************************************************************************* nulltsk bra * This is the null task. It is always runnable * and always interruptable. It does nothing * except provide an active task for the * Dispatcher when all other tasks are busy. * You may change this any way you wish as long * it is never put into a non-ready state. ******************************************************************************* ******************************************************************************* ******************************************************************************* * * * MCX11 INITIALIZATION * * * * This is the MCX11 Initialization routine in which all of the 68HC11 RAM and * * internal registers get initialized. This routine is entered upon a Power On * * RESET; therefore the first 64 cycles must be spent initializing those areas * * of the 68HC11 control register space which must be set up during that brief * * period. Then all of the system tables must be set to their initial content. * * The user should also include any initialization operatons unique to his own * * application. Upon completion, the routine should jump to the start of the * * MCX11 Dispatcher at lable "dispch". * * * ******************************************************************************* ******************************************************************************* * Put the special startup code here which must be done within the first * * 64 cycles after Power-on/Reset & set up the internal registers with * * respect to the application requirements. * ******************************************************************************* mcxinit equ * This is MCX11 entry point lds #SYSTACK ldaa #RTII staa TMSK2 Enable RTI Interrupt ldaa #RTR staa PACTL Set up RTI clock rate ******************************************************************************* * * * The following instruction is included for use with an EVM board. If you are * * going to want to initialize the EVM in such a manner that the MPU will use * * the first 64 cycles to initialize the control registers, leave this one * * instruction in place and perform the following startup procedure: * * * * 1. Press the USER RESET button on EVM board. * 2. Press ABORT SWITCH on EVM board. * 3. Ignore any ERROR MESSAGE from the EVM and press ENTER on your * * debug console@@s keyboard. This should show the Register set. * * 4. Change the content of Stack Pointer Register to legal value * * 5. Start the program with a G command at the address of @@mcxgo@@. * * * * If this is not used on an EVM board, and a normal RESET sequence is desired * * simply remove the following instruction. * * ******************************************************************************* bra * Just wait for the ABORT. ******************************************************************************* * The second job in the initialization process is to link all of the system * * timer blocks. The address of the first timer block is stored in the word * * in RAM labled "FREE". The word labled "ACTIVE" is set to a 0. * ******************************************************************************* mcxgo ldaa #TOCK staa tickcnt Set up Tick counter ldy #NTIMERS Set up counter for the number of timers ldd #TIMERS Get address of Timer Blocks std FREE Store it in the pointer to 1st free block ldx #TIMERS Set up pointer to 1st Timer Block tmlp dey Decrement timer counter and see if done. beq tmdone addd #TIMRLEN If not done, calculate address of next block std 0,x Store it in link word of current block. ldx 0,x Then set up pointer to the next block. bra tmlp tmdone clrb clra When done linking the timer blocks, set std 0,x the link word of the last timer to 0. std ACTIVE Set up 0 entry for no active timers. ******************************************************************************* * The third thing to do during initialization is to set up the queues. The * * queues have a Header and a Body and they are not contiguous. The Queue * * Headers are found immediately below the Timer Blocks in RAM. The Bodies are * * found immediately above the Task Control Blocks. * ******************************************************************************* ldx #QHDRTBL Set up pointer to the 1st queue header qlp clr 0,x Clear next byte in the queue header area. inx cpx #TIMERS See if all queue headers are cleared. bne qlp keep looping until done ******************************************************************************* * The fourth function during initialization is to set all of the semaphores * * to a PENDing state. The number of semaphores is equal to the number of the * * named semaphores + the number of tasks + twice the number of queues. * ******************************************************************************* ldaa #NQUEUES Get the number of queues in system. asla Multiply it by 2. adda #NNAMSEM Add the number of named semaphores adda #NTASKS Then add the number of tasks. ldx #FLGTBL Set up pointer to base of the semaphores. ldab #_PEND smlp stab 0,x Store the PENDing value in the semaphore. inx deca Decrement the counter bne smlp Keep looping until all are set to PENDing. ******************************************************************************* * The fifth thing to do in the initialization is to set up the RAM resident * * portions of the Task Control Blocks (TCB). The TCBs are found immediately * * above the semaphores. * ******************************************************************************* ldy #TCBDATA Set up pointer to User Defined list of * TCB initialization data block. ldaa #NTASKS Set up task counter too. staa notmt tcblp ldx TCBADDR,y Set up a pointer to the TCB. clr MSGTHRD,x Clear the message thread. clr MSGTHRD+1,x ldab INITST,y Get the initial status of the task. stab STATE,x Store it as the status byte of the TCB. bne nostart Branch if task state show it is not ready. ldd RSTSP,y subd #9 std ACTSP,x Set up pointer to the stack context. xgdx Put stacked context address into IX. ldd STRTADR,y std PC+1,x Put task@@s starting address into PC word clra of the context. Then clear ACCB, ACCA, clrb and CCR. staa CCR+1,x std ACCB+1,x nostart ldab #TCBDATL aby Bump pointer to next TCB initialization dec notmt data block. bne tcblp Loop until done. * Now set up the null task ldx #SYSTACK+9 ldd #nulltsk Get the starting address of the null task. std PC+1,x Put task@@s starting address into PC word clr CCR+1,x of the context. Then clear ACCB, ACCA, clr ACCB+1,x and CCR. clr ACCA+1,x ldd #NTASKS*TCBLEN+STATLS Get TCB address of the null task xgdx std ACTSP,x Save address of null task@@s context clr STATE,x Make sure null task is READY. clr intlvl Clear interrupt level. ** (V1.1 #5) * jmp dispch Start the MCX Dispatcher ******************************************************************************* * The next location should contain the entry point to the Dispatcher. * * The file "MCX.AS" should follow this file. If not, then you should remove * * the asterisk on the line above which causes a direct jump to the label of * * the Dispatcher, "dispch". * *******************************************************************************