Microsoft Programmer's Library 1.3

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Text File | 1988-11-10 | 11.8 KB | 399 lines

Figure 2 Sample Microsoft C Start-Up Routine for Embedded Applications NAME STARTUP_CODE ; THIS IS A SAMPLE START-UP PROGRAM FOR AN EMBEDDED SYSTEM. ; THE MEMORY LAYOUT CONFORMS TO THE NAMING CONVENTION USED ; IN MICROSOFT C, VERSION 4.X AND 5.X. ; THIS ASSEMBLY FILE SHOULD BE ASSEMBLED USING MICROSOFT ; MASM ASSEMBLER USING THE FOLLOWING COMMAND, ASSUMING THIS ; FILE IS CALLED STARTUP.ASM: ; >MASM STARTUP/MX,STARTUP,STARTUP,NUL ; THE /MX OPTION IS USED TO PRESERVE LOWER-CASE IN PUBLIC ; AND EXTERNAL NAMES. ; ; SETUP OF SEGMENT CLASSES IN MICROSOFT C 5.X PROGRAMS. ; ; HIGH ADDRESS ; - ------------- ; | |'BOOTSTRAP'| ; | ------------- ; | : : ; | : : ; R ------------- ---THESE TWO CLASSES ARE TO BE ; O | 'CONST' | ^ COPIED TO THEIR RAM ; M ------------- | LOCATIONS AT POWER-UP ; | | 'DATA' | v ; | ------------- <---ROMCODE_END SEGMENT ; | | 'CODE' | ; - ------------- <---ROMCODE_BEG SEGMENT ; : : ; : : ; - ------------- <---UDATA_END SEGMENT ; | | 'STACK' | ; | ------------- ; | | 'BSS' | ; | ------------- <---IDATA_END & UDATA_BEG ; | | 'CONST' | ^ SEGMENTS ; R ------------- |--THESE TWO CLASSES ARE TO BE ; A | 'DATA' | v INITIALIZED BY START-UP ; M ------------- <-- ROUTINE AT POWER-UP ; | : : | ; | : : |-IDATA_BEG SEGMENT ; | ------------- ; | | 'INT_PTR' | ; - ------------- ; LOW ADDRESS ; ; CHOOSE THE MEMORY MODEL BY SETTING THE APPROPRIATE LABEL ; TO 1. ; SMALL EQU 0 COMPACT EQU 0 MEDIUM EQU 0 LARGE EQU 1 HUGE EQU 0 STACK_SIZE EQU 400H ; RESERVE 1K WORD OF STACK OR ANY SIZE YOU WANT __acrtused EQU 1 ; IT IS USED TO SATISFY THE EXTERNAL REFERENCE ; FOUND IN EVERY OBJECT FILE GENERATED ; BY THE MICROSOFT C COMPILER, VER 5.X PUBLIC __acrtused ; THE SYMBOL HAS TO BE IN LOWER-CASE DGROUP GROUP IDATA_BEG,_DATA,CONST,IDATA_END,UDATA_BEG,_BSS,STACK,UDATA_END ;THIS SEGMENT MARKS THE BEGINNING OF ROM CODE ROMCODE_BEG SEGMENT PARA 'ROMCODE_BEG' ROMCODE_BEG ENDS IF SMALL OR COMPACT _TEXT SEGMENT BYTE PUBLIC 'CODE' EXTRN _main:NEAR ;C main() ASSUME CS:_TEXT ENDIF IF MEDIUM OR LARGE OR HUGE EXTRN _main:FAR ;C main() STARTUP_TEXT SEGMENT BYTE PUBLIC 'CODE' ASSUME CS:STARTUP_TEXT ENDIF ASSUME DS:DGROUP, SS:DGROUP PUBLIC START START: START_I2ICE LABEL BYTE ; ADDRESS LABEL FOR INTEL I2ICE CLI CLD ; ************************************************************ ; *** YOUR CODE HERE TO DO HARDWARE INITIALIZATION ; AND RAM CHECK *** ************************************************************ PUBLIC INIT_RAM_DATA INIT_RAM_DATA: INIT_RAM_DATA_I2ICE LABEL BYTE ; ADDRESS LABEL FOR INTEL ; I2ICE ; *** TRANSFER INITIALIZATION DATA FROM ROM TO RAM *** ; COMPUTE THE SIZE OF 'DATA' AND 'CONST' CLASS IN NO. OF PARAGRAPHS: MOV AX,SEG IDATA_END ; FRAME NO. OF IDATA_END SEGMENT ; = END OF 'CONST' CLASS IN RAM MOV BX,SEG IDATA_BEG ; FRAME NO. OF IDATA_BEG SEGMENT ; = START OF 'DATA' CLASS IN RAM SUB AX,BX ; AX = SIZE OF 'DATA' & 'CONST' CLASSES MOV CL,3 ; SET UP TO MULTIPLE BY 8 SHL AX,CL ; COMPUTE NO. OF WORDS TO BE TRANSFERRED MOV CX,AX ; TRANSFER COUNTER JCXZ NO_IDATA_DATA ; OBTAIN THE FRAME NO. OF 'DATA' CLASS PLACED IN ROM MOV AX,SEG ROMCODE_END ; FRAME NO. OF ROMCODE_END SEGMENT ; = BEGINNING OF 'DATA' CLASS IN ROM MOV DS,AX ; SOURCE STRING MOV SI,0 ; OBTAIN THE FRAME NO. OF 'DATA' CLASS LOCATED IN RUN-TIME RAM SPACE MOV AX,SEG IDATA_BEG ; FRAME NO. OF IDATA_BEG SEGMENT ; = BEGINNING OF 'DATA' CLASS IN RAM MOV ES,AX ; DESTINATION STRING MOV DI,0 ; INITIALIZE THE 'DATA' AND 'CONST' CLASSES IN ; RUN-TIME RAM SPACE REP MOVSW ; BEGIN WORD TRANSFER PUBLIC NO_IDATA_DATA NO_IDATA_DATA: NO_IDATA_DATA_I2ICE LABEL BYTE ; ADDRESS LABEL FOR ; INTEL I2ICE ; *** CLEAR UNINITIALIZED DATA *** ; COMPUTE THE SIZE OF 'BSS' & 'STACK' CLASSES IN NO. OF ; PARAGRAPHS: MOV AX,SEG UDATA_END ; FRAME NO. OF UDATA_END SEGMENT ; = END OF 'STACK' CLASS IN RAM MOV BX,SEG UDATA_BEG ; FRAME NO. OF UDATA_BEG SEGMENT ; = START OF 'BSS' CLASS IN RAM SUB AX,BX ; AX = SIZE IN PARAGRAPHS MOV CL,3 ; SET UP TO MULTIPLE BY 8 SHL AX,CL ; COMPUTE NO. OF WORDS TO BE INITIALIZED MOV CX,AX ; SETUP COUNTER JCXZ NO_UDATA MOV ES,BX ; SETUP DESTINATION POINTER MOV DI,0 MOV AX,0 ; INITIALIZE TO 0 REP STOSW PUBLIC NO_UDATA NO_UDATA: NO_UDATA_I2ICE LABEL BYTE ; ADDRESS LABEL FOR INTEL I2ICE ; *** SETUP DATA AND STACK SEGMENT *** MOV AX,DGROUP MOV DS,AX ; SETUP DATA SEGMENT MOV SS,AX ; SETUP STACK POINTER MOV SP,OFFSET DGROUP:STACK_TOP STI ; ENABLE INTERRUPT NOW JMP _main ; ENTER C main() FUNCTION HLT IF SMALL OR COMPACT _TEXT ENDS ENDIF IF MEDIUM OR LARGE OR HUGE STARTUP_TEXT ENDS ENDIF ;THIS SEGMENT MARKS THE END OF ROM CODE ROMCODE_END SEGMENT PARA 'ROMCODE_END' ROMCODE_END ENDS ; *** THE FOLLOWING SEGMENTS ARE ALL LOCATED IN RAM *** INT_PTR SEGMENT AT 0H ;'INT_PTR' ;INTERRUPT POINTER TABLE, LOCATE AT 0H IN RAM. PUBLIC TYPE_0,TYPE_1,TYPE_2,TYPE_3,TYPE_4,TYPE_32 TYPE_0 DD ? ;DIVIDE-ERROR TYPE_1 DD ? ;SINGLE-STEP TYPE_2 DD ? ;NON-MASKABLE INTERRUPT TYPE_3 DD ? ;BREAKPOINT TYPE_4 DD ? ;OVERFLOW ;SKIP INTEL RESERVED VECTORS ORG 32 * 4 TYPE_32 DD ? ;MAY PLACE YOUR VECTORS HERE ;MORE INTERRUPT VECTORS INT_PTR ENDS ; THIS SEGMENT MARKS THE BEGINNING OF DGROUP AND INITIALIZED DATA IN RAM IDATA_BEG SEGMENT PARA PUBLIC 'IDATA_BEG' IDATA_BEG ENDS _DATA SEGMENT WORD PUBLIC 'DATA' _DATA ENDS CONST SEGMENT WORD PUBLIC 'CONST' CONST ENDS ; THIS SEGMENT MARKS THE END OF INITIALIZED DATA IN RAM IDATA_END SEGMENT PARA PUBLIC 'IDATA_END' IDATA_END ENDS ; THIS SEGMENT MARKS BEGINNING OF UNINITIALIZED DATA IN RAM UDATA_BEG SEGMENT PARA PUBLIC 'UDATA_BEG' UDATA_BEG ENDS _BSS SEGMENT WORD PUBLIC 'BSS' _BSS ENDS STACK SEGMENT PARA STACK 'STACK' DW STACK_SIZE DUP (?) STACK_TOP LABEL WORD STACK ENDS ; THIS SEGMENT MARKS THE END OF UNINITIALIZED DATA IN RAM UDATA_END SEGMENT PARA PUBLIC 'UDATA_END' UDATA_END ENDS ; THIS SEGMENT CONTAINS BOOTSTRAP CODE AT HARDWARE RESET OR ; POWER-UP ; FAR JUMP TO PROGRAM START, LOCATE AT FFFF0H IN ROM. BOOTSTRAP SEGMENT AT 0FFFFH ;'BOOTSTRAP' JMP FAR PTR START BOOTSTRAP ENDS END START Extra Figure (not used in article) Example of a Locator Map File REX 8086/8087/8088/80186 OBJECT CODE LOCATER, V5.0 TIME: 14:55:23 08-10-1988 INPUT FILES: SAMPLE.LNK OUTPUT FILE: SAMPLE.ABS CONTROLS SPECIFIED IN INVOCATION COMMAND: ORDER(CLASSES(IDATA_BEG,DATA,CONST,IDATA_END, UDATA_BEG,BSS,STACK,FAR_BSS,UDATA_END, DEBSYM,DEBTYP, ROMCODE_BEG,CODE,ROMCODE_END)) ADDRESSES(CLASSES(IDATA_BEG(200H), DEBSYM(20000H), ROMCODE_BEG(0E0000H))) NOINITCODE SYMBOL TABLE OF MODULE startup BASE OFFSET TYPE SYMBOL BASE OFFSET TYPE SYMBOL E000H 0002H PUB INIT_RAM_DATA E000H 0024H PUB NO_IDATA_DATA E000H 003EH PUB NO_UDATA E000H 0000H PUB START 0000H 0000H PUB TYPE_0 0000H 0004H PUB TYPE_1 0000H 0008H PUB TYPE_2 0000H 000CH PUB TYPE_3 0000H 0080H PUB TYPE_32 0000H 0010H PUB TYPE_4 0000H 0001H PUB __acrtused 0020H 0008H PUB _count 0020H 0000H PUB _in_ptr E005H 0000H PUB _main 0020H 0004H PUB _out_ptr 00A1H 0080H PUB _picmask E005H 0086H PUB _process_data 00A1H 0000H PUB _ring_buf E005H 0092H PUB _sio_handler MODULE = startup BASE OFFSET TYPE SYMBOL BASE OFFSET TYPE SYMBOL E000H 0000H LIN 77 E000H 0001H LIN 78 E000H 0002H LIN 88 E000H 0005H LIN 90 E000H 0008H LIN 92 E000H 000AH LIN 93 E000H 000CH LIN 94 E000H 000EH LIN 95 E000H 0010H LIN 96 E000H 0012H LIN 100 E000H 0015H LIN 102 E000H 0017H LIN 103 E000H 001AH LIN 107 E000H 001DH LIN 109 E000H 001FH LIN 110 E000H 0022H LIN 114 E000H 0024H LIN 122 E000H 0027H LIN 124 E000H 002AH LIN 126 E000H 002CH LIN 127 E000H 002EH LIN 128 E000H 0030H LIN 129 E000H 0032H LIN 130 E000H 0034H LIN 131 E000H 0036H LIN 132 E000H 0039H LIN 133 E000H 003CH LIN 134 E000H 003EH LIN 141 E000H 0041H LIN 142 E000H 0043H LIN 143 E000H 0045H LIN 144 E000H 0048H LIN 145 E000H 0049H LIN 146 E000H 004EH LIN 147 FFFFH 0000H LIN 208 MODULE = main BASE OFFSET TYPE SYMBOL BASE OFFSET TYPE SYMBOL E005H 0000H LIN 27 E005H 0018H LIN 28 E005H 001FH LIN 30 E005H 002FH LIN 31 E005H 0047H LIN 32 E005H 004BH LIN 33 E005H 0065H LIN 34 E005H 006FH LIN 35 E005H 0083H LIN 37 E005H 0086H LIN 41 E005H 0089H LIN 43 E005H 0090H LIN 44 E005H 0092H LIN 47 E005H 00A4H LIN 48 E005H 00A5H LIN 49 E005H 00AEH LIN 50 E005H 00C8H LIN 51 E005H 00D2H LIN 52 E005H 00DAH LIN 53 E005H 00DEH LIN 54 E005H 00E3H LIN 55 MEMORY MAP OF MODULE startup MODULE START ADDRESS PARAGRAPH = E000H OFFSET = 0000H SEGMENT MAP START STOP LENGTH ALIGN NAME CLASS OVERLAY 00000H 00083H 0084H A INT_PTR 00200H 00200H 0000H G IDATA_BEG IDATA_BEG 00200H 00209H 000AH W _DATA DATA 0020AH 0020BH 0002H W CONST CONST 00210H 00210H 0000H G IDATA_END IDATA_END 00210H 00210H 0000H G UDATA_BEG UDATA_BEG 00210H 00210H 0000H W _BSS BSS 00210H 00A0FH 0800H G STACK STACK 00A10H 00A90H 0081H G FAR_BSS_1 FAR_BSS 00AA0H 00AA0H 0000H G UDATA_END UDATA_END 20000H 20074H 0075H G $$SYMBOLS DEBSYM 20075H 200F6H 0082H B $$SYMBOLS DEBSYM 20100H 2010BH 000CH G $$TYPES DEBTYP 2010CH 20197H 008CH B $$TYPES DEBTYP E0000H E0000H 0000H G ROMCODE_BEG ROMCODE_BEG E0000H E004EH 004FH B STARTUP_TEXT CODE E0050H E013DH 00EEH W MAIN_TEXT CODE E0140H E0140H 0000H G ROMCODE_END ROMCODE_END FFFF0H FFFF4H 0005H A BOOTSTRAP GROUP MAP ADDRESS GROUP OR SEGMENT NAME 00200H DGROUP IDATA_BEG\\IDATA_BEG\\ _DATA\\DATA\\ CONST\\CONST\\ IDATA_END\\IDATA_END\\ UDATA_BEG\\UDATA_BEG\\ _BSS\\BSS\\ STACK\\STACK\\ UDATA_END\\UDATA_END\\ Figure 6 C Source for functions that implement a Ring Buffer /* To generate in-line 8086 opcodes for intrinsic functions, such as inp, outp, and _enable, specify /Oi in C compiler */ #define RING_BUF_SIZ 128 #define PICIER 0xC2 #define PICEOI 0xC0 #define IRQDIS 0x20 #define EOI 0x20 #define SIOPORT 0x10 #define OUTPORT 0x12 #define enable_sio() picmask = inp(PICIER); \\ picmask &= (~IRQDIS); \\ outp(PICIER, picmask); #define disable_sio() picmask = inp(PICIER); \\ picmask |= IRQDIS; \\ outp(PICIER, picmask); char ring_buf[RING_BUF_SIZ]; char *in_ptr = ring_buf; char *out_ptr = ring_buf; int count = 0; char picmask; void process_data(char); main() { while(1) { enable_sio(); /* enable serial i/o */ if (count > 0) { process_data(*out_ptr); disable_sio(); /* disable serial i/o */ count--; if (out_ptr++ == ring_buf + RING_BUF_SIZ) out_ptr = ring_buf; /* ring buffer */ enable_sio(); /* enable serial i/o */ } } } void process_data(c) char c; { outp(OUTPORT, c); } void interrupt far sio_handler() { _enable(); /* enable higher order interrupt */ *in_ptr = inp(SIOPORT); if (in_ptr++ == ring_buf + RING_BUF_SIZ) in_ptr = ring_buf; if (count != RING_BUF_SIZ) count++; outp(PICEOI, EOI); /* reset interrupt */ }