AN541

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1 深圳市英锐恩科技有限公司单片机集成方案全方位解决服务商优质智能电子产品芯方案解决商 Microchip 产品用户参考手册深圳市英锐恩科技有限公司 ENROO-TECH(SHENZHEN)CO.,LTD 中国深圳市福田区福华路嘉汇新城汇商中心 27 楼 2701 Enroo-Tech Technologies CO., Limited Light-Tech International Limited 香港新界荃灣沙咀道號科技中心 5 樓 5 室联系电话 : , , , , 联系传真 : 联系邮件 :enroo@enroo.com 公司网站 : ; Add: 深圳市福田区福华路嘉汇新城汇商中心 27 楼 2701 Tel: , Fax:

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7 00014 IF (CPU==1654) (CPU==1655) FF _RESVEC EQU 01FFH ;16c54 start address ENDIF IF CPU== _RESVEC EQU 03FFH ;16C56 start address ENDIF IF CPU== _RESVEC EQU 07FFH ;16C57 start address ENDIF ;*** Reset Vector ******************************************* FF ORG _RESVEC ; 01FF RESVEC ; 01FF 0A0B GOTO INIT ; ;*********************************************************** ;*********************************************************** ;* Macros to set/clear/branch/skip on bits ;* These macros define and use synthetic bit labels ;* Bit labels contain the address and bit of a location ;* ;********************************************************************** ;* Usage Description ;* ;* BIT label,bit,file ;Define a bit label ;* SEB label ;set bit using bit label ;* CLB label ;clear bit using bit label ;* SKBS label ;SKIP on bit set ;* SKBC label ;SKIP on bit clear ;* BBS label,address ;BRANCH on bit set ;* BBC label,address ;BRANCH on bit clear ;* CBS label,address ;CALL on bit set ;* CBC label,address ;CALL on bit clear ;* ;********************************************************************** BIT MACRO label,bit,file ;Define a bit label label EQU file<<8 bit ;(macro) ENDM ; 00057

8 00058 SEB MACRO label ;Set bit BSF label>>8,label &7 ;(macro) ENDM ; CLB MACRO label ;Clear bit BCF label>>8,label &7 ;(macro) ENDM ; SKBS MACRO label ;Skip on bit set BTFSS label>>8,label &7 ;(macro) ENDM SKBC MACRO label ;Skip on bit clear BTFSC label>>8,label &7 ;(macro) ENDM BBS MACRO label,address ;Branch on bit set BTFSC label>>8,label &7 ;(macro) GOTO address ;(macro) ENDM ; BBC MACRO label,address ;Branch on bit clear BTFSS label>>8,label &7 ;(macro) GOTO address ;(macro) ENDM CBS MACRO label,address ;Call on bit set CALL label>>8,label &7 ;(macro) ENDM ; CBC MACRO label,address ;Call on bit clear CALL label>>8,label &7 ;(macro) ENDM ;For Assembler portability W EQU 0 ;For file,w w EQU 0 ;For file,w F EQU 1 ;For file,f f EQU 1 ;For file,f ;******************************************************************* ;* REGISTER DECLARATIONS

9 00102 ;******************************************************************* ORG 0 ;ORG for register declarations ind RES 1 ;0=pseudo-reg 0 for in direct (FSR) TMR0 RES 1 ;1=real time counter PC RES 1 ;2=PC STATUS RES 1 ;3=status reg ;* Status reg bits BIT B_C,0,STATUS ;Carry M B_C EQU STATUS<<8 0 ;(macro) BIT B_DC,1,STATUS ;Half carry M B_DC EQU STATUS<<8 1 ;(macro) BIT B_Z,2,STATUS ;Zero M B_Z EQU STATUS<<8 2 ;(macro) BIT B_PD,3,STATUS ;Power down M B_PD EQU STATUS<<8 3 ;(macro) BIT B_TO,4,STATUS ;Timeout M B_TO EQU STATUS<<8 4 ;(macro) BIT B_PA0,5,STATUS ;Page select (56/57 only) M B_PA0 EQU STATUS<<8 5 ;(macro) BIT B_PA1,6,STATUS ;Page select (56/57 only) M B_PA1 EQU STATUS< ;(macro) BIT B_PA2,7,STATUS ;GP flag M B_PA2 EQU STATUS<<8 7 ;(macro) FSR RES 1 ;4=file select reg 0-4 =indirect address PORTA RES 1 ;5=port A I/O register (4 bits) PORTB RES 1 ;6=port B I/O register IF (CPU==1655) (CPU==1657) PORTC RES 1 ;7=I/O port C on 16C54/56 only ENDIF ;registers used by this code I2CFLG RES 1 ;I2C flag reg ;--i2c flags BIT B_RD,0,I2CFLG ;Flag: 1=read M B_RD EQU I2CFLG<<8 0 ;(macro) BIT B_UA,1,I2CFLG ;Flag: 0=reading unit address

10 M B_UA EQU I2CFLG<<8 1 ;(macro) BIT B_SA,2,I2CFLG ;Flag: 1=reading subabbress M B_SA EQU I2CFLG<<8 2 ;(macro) BIT B_ID,3,I2CFLG ;Flag: 1=reading id M B_ID EQU I2CFLG<<8 3 ;(macro) ; I2CREG RES 1 ;I2C I/O register I2CSUBA RES 1 ;Subaddress 000A I2CBITS RES 1 ;I2C xmit bit counter ;********************************************************************** ;* 8 Pseudo registers accessed by sub-addresses ;* (address 0 accesses the ID string) ;* these are read-write registers ;********************************************************************** B I2CR0 EQU $ ;Sub-address 8 000B RES 1 ;8 pseudo registers C I2CR1 EQU $ ;Sub-address 1 000C RES D I2CR2 EQU $ ;Sub-address 2 000D RES E I2CR3 EQU $ ;Sub-address 3 000E RES F I2CR4 EQU $ ;Sub-address 4 000F RES I2CR5 EQU $ ;Sub-address RES I2CR6 EQU $ ;Sub-address RES I2CR7 EQU $ ;Sub-address RES ;Constants used by program 00177

11 000000D DEVICE_ADDRESS EQU 0D6H ;I2C device address (device_address+1 = read) ;************************************************************** ;** PORTA DEFINITIONS ;** I2C interface uses PORTA ;** note SDA goes to A0 for code efficiency ;** ;*************************************************************** F TAREAD EQU B ;TRISA register for SDA read F TAWRITE EQU B ;TRISA register for SDA write F TAINIT EQU TAREAD ;Initial TRISA value BIT B_SDA,0,PORTA ;I2C SDA (data) This must be bit 0! M B_SDA EQU PORTA<<8 0 ;(macro) BIT B_SCL,1,PORTA ;I2C SCL (clock) M B_SCL EQU PORTA<<8 1 ;(macro) ;spare B_???,2,PORTA ;not used ;spare B_???,3,PORTA ;not used ;************************************************************** ;** ;** Port B definition (Parallel out) ;** ;**************************************************************** TBINIT EQU B ;Port B tris (all output) FF PBINIT EQU B ;Port B init ;********************************************************************** ;* Macros to contain user POLL loop code ;* These are implemented as macros to allow ease of modification, ;* especially in real-time applications. The functions could be coded ;* as in-line code or as subroutines depending on ROM/time tradeoffs ;* ;* USER_MAIN: Decision or code to perform at idle time ;* ;* USER_Q: Quick code for use during transfer - max 8 Ês for ;* full I2C Spec. More than 4s may result in I2C ;* retries (at full spec speed ;* ;* USER_MSG: Code to execute at receipt of I2C command ;*

12 00220 ;********************************************************************** USER_MAIN MACRO ;*** This would be user code for idle loop ENDM USER_Q MACRO ;*** This would be quick user code ENDM USER_MSG MACRO ;*** This would be user code to process a message ENDM USER_RECV MACRO ;*** This would be user code to process a received byte ;*** example code sends sub-address 0 to port b BBC B_ID,_NXI_notid ;Channel 0! Bit set if INITIAL address was MOVFW I2CREG ;get received byte MOVWF PORTB ;and write it on portb GOTO IN_CONT _NXI_notid ENDM USER_XMIT MACRO ;*** This would be user code to prepare an output byte ;*** example code sends id string to output BBC B_ID,_NXO_notid ;Channel 0! Bit set if INITIAL address was CALL GETID ;get next byte from ID channel GOTO OUT_CONT ;and send it _NXO_notid ENDM ;******************************************************************* ; START OF CODE ;******************************************************************* ORG ;******************************************************************* ;* Device ID Table (must be at start) ;* TABLE FOR UNIT ID returns next char in W ;******************************************************************* GETID MOVFW I2CSUBA ;W=I2CSUBA E ANDLW 07H ;Limit to 8 locations

13 E ADDWF PC,F ;********************************************************************** ;* Device ID text: read starting at sub-address ;********************************************************************** RETLW P RETLW I RETLW C RETLW I RETLW RETLW C RETLW 0 000A RETLW ;********************************************************************** ;* I2C Device routines ;* ;* Enable must be HIGH, else state goes to ;* write is to me, read is from me ;* ;* <============== first byte / subsequent writes =====> <end> ;* ;* SDA -- X-----X-----X-----X-----X-----X-----X-----X---X ;* ---X-----X-----X-----X-----X-----X-----X-----X---X****** ;* (bit) s ackout ;* SCL ;* ;* ;* STATE: ;* ;* <============== subsequant reads ===================> ;* ;* SDA X-----X-----X-----X-----X-----X-----X-----X----X------X ;* --X-----X-----X-----X-----X-----X-----X-----X----X******X ;* (bit)ack ackin ;* SCL ;* ;* ;* STATE: A ;* ;* <============== Final READ =========================> ;*

14 00308 ;* SDA X-----X-----X-----X-----X-----X-----X-----X----X- ** ;* --X-----X-----X-----X-----X-----X-----X-----X----X* ;* (bit)ack ackin ;* SCL ;* ;* ;* STATE: A ;* ;* STATE B is an ignore bit state for non-addressed bits ;* STATE C indicates last sample had ENA low on rising ;* edge of ENA, DATA LOW = low voltage, DATA&CLOCK low = RESET ;***************************************************************** ;I2C interface uses PORTA ;note SDA must be on PORTA,0 for code efficiency ;***************************************************************** ;** INIT ;** Hardware reset entry point ;** ;***************************************************************** 000B INIT ;Power-on entry ;***************************************************************** ;** RESET ;** software reset entry point ;** ;***************************************************************** 000B RESET ;Soft reset B 0CF MOVLW TAINIT ;Init ports 000C TRIS PORTA 000D 0C MOVLW TBINIT 000E TRIS PORTB 000F 0CFF MOVLW PBINIT MOVWF PORTB ;***************************************************************** ; Main wait loop while idle. POLL loop should be called here ; ;***************************************************************** I2CWAIT CLRWDT ;Clear watchdog timer

15 00352 CLB B_UA ;Init state flags M BCF B_UA>>8,B_UA&7 ;(macro) CLB B_SA ;Init state flags M BCF B_SA>>8,B_SA&7 ;(macro) CLB B_RD ;Init state flags M BCF B_RD>>8,B_RD&7 ;(macro) loop CLRWDT ;Clear watchdog timer USER_MAIN ;Call user code while in idle state M ;*** This would be user code for idle loop SKBC B_SDA ;Wait for SDA&SCL=H M BTFSC B_SDA>>8,B_SDA&7 ;(macro) loop SKBS B_SCL ; M BTFSS B_SCL>>8,B_SCL&7 ;(macro) A GOTO loop1 ; No longer valid to wait for start! CLRWDT ;Clear watchdog timer USER_MAIN ;Call user code while in idle state M ;*** This would be user code for idle loop ;** wait for start ** SKBC B_SCL ;Clock has dropped 001A 0625 M BTFSC B_SCL>>8,B_SCL&7 ;(macro) SKBC B_SDA ;Data dropped... Start! 001B 0605 M BTFSC B_SDA>>8,B_SDA&7 ;(macro) 001C 0A GOTO loop ;** START RECEIVED! --- wait for first bit! 001D loop BBS B_SDA,I2CWAIT ;Data raised before clock dropped -- abort 001D 0605 M BTFSC B_SDA>>8,B_SDA&7 ;(macro) 001E 0A11 M GOTO I2CWAIT ;(macro) BBS B_SCL,loop3 ;Wait for clock low 001F 0625 M BTFSC B_SCL>>8,B_SCL&7 ;(macro) A1D M GOTO loop3 ;(macro) NEXTBYTE CLRWDT ;Clear watchdog timer

16 0022 0C MOVLW 1 ;Init receive byte so bit falls off at end! MOVWF I2CREG ;*Shift bits! external poll may be executed during low clock cycle only! ;*ENABLE line is checked for loss of enable ONLY during HIGH CLOCK ;*** CLOCK IS LOW -- DATA MAY CHANGE HERE ;*** We have at least 4 Ês before any change can occur loop USER_Q M ;*** This would be quick user code loop4a BBC B_SCL,loop4A ;Wait for clock high M BTFSS B_SCL>>8,B_SCL&7 ;(macro) A24 M GOTO loop4a ;(macro) ;*** CLOCK IS HIGH -- SHIFT BIT - then watch for chang e RRF PORTA,W ;Move RA0 into C RLF I2CREG,F ;Shift in bit SKPNC ;Skip if not done A GOTO ACK_I2C ;Acknowledge byte A BTFSC I2CREG,0 ;Skip if data bit was 0 002B 0A GOTO ii_1 ;This bit was set 002C ii_ BBC B_SCL,loop4 ;Wait for clock low 002C 0725 M BTFSS B_SCL>>8,B_SCL&7 ;(macro) 002D 0A24 M GOTO loop4 ;(macro) SKBS B_SDA ;Data low-high == stop 002E 0705 M BTFSS B_SDA>>8,B_SDA&7 ;(macro) 002F 0A2C GOTO ii_ I2CSTOP USER_MSG ;process completed message! M ;*** This would be user code to process a message A GOTO I2CWAIT ;back to main loop ii_1 BBC B_SDA,I2CWAIT ;Data high-low == start M BTFSS B_SDA>>8,B_SDA&7 ;(macro) A11 M GOTO I2CWAIT ;(macro) BBC B_SCL,loop4 ;Wait for clock low M BTFSS B_SCL>>8,B_SCL&7 ;(macro) A24 M GOTO loop4 ;(macro)

17 0035 0A GOTO ii_ ACK_I2C BBC B_UA,ACK_UA ;Not addressed - check unit address M BTFSS B_UA>>8,B_UA&7 ;(macro) A8B M GOTO ACK_UA ;(macro) BBS B_SA,ACK_SA ;Reading secondary address M BTFSC B_SA>>8,B_SA&7 ;(macro) A97 M GOTO ACK_SA ;(macro) ;**** ;** Do what must be done with new data bytes here (before ACKloop) ;** Don t ack if byte can t be processed! ;**** ; USER_RECV M ;*** This would be user code to process a received byte M ;*** example code sends sub-address 0 to port b M BBC B_ID,_NXI_notid ;Channel 0! Bit set if INITIAL address was 0 003A 0767 M BTFSS B_ID>>8,B_ID&7 ;(macro) 003B 0A3F M GOTO _NXI_notid ;(macro) 003C 0208 M MOVFW I2CREG ;get received byte 003D 0026 M MOVWF PORTB ;and write it on portb 003E 0A47 M GOTO IN_CONT 003F M _NXI_notid F 0C MOVLW 07H ;Register count ANDWF I2CSUBA,f ;Limit register count C0B MOVLW I2CR0 ;Pseudo-registers C ADDWF I2CSUBA,W ;Offset from buffer start A INCF I2CSUBA, F ;Next sub-address MOVWF FSR ;Indirect address MOVFW I2CREG MOVWF ind ;Put data into register IN_CONT ;continue point for intercepted bytes ACKloop BBS B_SCL,ACKloop ;Wait for clock low M BTFSC B_SCL>>8,B_SCL&7 ;(macro) A47 M GOTO ACKloop ;(macro) CLB B_SDA ;Set ACK

18 M BCF B_SDA>>8,B_SDA&7 ;(macro) 004A 0CF MOVLW TAWRITE 004B TRIS PORTA CLB B_SDA ;Set ACK (just in case docs are wrong) 004C 0405 M BCF B_SDA>>8,B_SDA &7 ;(macro) D ACKloop USER_Q M ;*** This would be quick user code BBC B_SCL,ACKloop2 ;Wait for clock high 004D 0725 M BTFSS B_SCL>>8,B_SCL&7 ;(macro) 004E 0A4D M GOTO ACKloop2 ;(macro) F ACKloop USER_Q M ;*** This would be quick user code BBS B_SCL,ACKloop3 ;Wait for clock low 004F 0625 M BTFSC B_SCL>>8,B_SCL&7 ;(macro) A4F M GOTO ACKloop3 ;(macro) CF MOVLW TAREAD ;End ACK TRIS PORTA BBC B_RD,NEXTBYTE ;Skip if read (we were acking address only) M BTFSS B_RD>>8,B_RD&7 ;(macro) A21 M GOTO NEXTBYTE ;(macro) ;********************************************************************* ; I2C Readback (I2C read request) ; Application specific code to get bytes to send may be added here ; This routine gets data from location pointed to by I2CSUBA and ; sends it to I2C. Subsequent reads get sequential addresses. This ; version AND s the register # with 7 to limit to 8 registers (for ; speed). Thiscould be modified to do a comparison to an Absolute ; number ;********************************************************************* NEXTOUT ;*** <<< PUT NEXT BYTE INTO I2CREG HERE NOW! >>> *** USER_XMIT

19 M ;*** This would be user code to prepare an output byte M ;*** example code sends id string to output M BBC B_ID,_NXO_notid ;Channel 0! Bit set if INITIAL address was M BTFSS B_ID>>8,B_ID&7 ;(macro) A59 M GOTO _NXO_notid ;(macro) M CALL GETID ;get next byte from ID channel A60 M GOTO OUT_CONT ;and send it 0059 M _NXO_notid C MOVLW 07H ;Register count 005A ANDWF I2CSUBA,f ;Limit register count 005B 0C0B MOVLW I2CR0 ;Pseudo-registers 005C 01C ADDWF I2CSUBA,W ;Offset from buffer start 005D 02A INCF I2CSUBA, F ;Next sub-address 005E MOVWF FSR ;Indirect address 005F MOVFW ind ;Get data from register OUT_CONT MOVWF I2CREG ;-- add code here to init I2CREG! when B_ID is clear! C MOVLW 8 ;Bit counter A MOVWF I2CBITS ;** OUT bits! -- external poll may be executed during low clock cycle, ; but may also be executed during high cycle if necessary ;* ENABLE line is checked for loss of enable ONLY during HIGH CLOCK ;*** CLOCK IS LOW -- CHANGE DATA HERE FIRST! ;*** loop 1: data was iiout_loop_ RLF I2CREG,F ;Shift data out, MSB first SKPNC ;1->0: change A GOTO iiout_1 ;Output another 1! CLB B_SDA ;Output M BCF B_SDA>>8,B_SDA&7 ;(macro) CF MOVLW TAWRITE TRIS PORTA CLB B_SDA ;Set data (just in case docs are wrong) M BCF B_SDA>>8,B_SDA&7 ;(macro) A iiout_0 006A CLRWDT ;Clear watchdog timer

20 USER_Q M ;*** This would be quick user code B iiout_loop_ BBC B_SCL,iiOUT_loop_02 ;Wait for clock high 006B 0725 M BTFSS B_SCL>>8,B_SCL&7 ;(macro) 006C 0A6B M GOTO iiout_loop_02 ;(macro) USER_Q M ;*** This would be quick user code D iiout_loop_ BBS B_SCL,iiOUT_loop_03 ;Wait for clock low 006D 0625 M BTFSC B_SCL>>8,B_SCL&7 ;(macro) 006E 0A6D M GOTO iiout_loop_03 ;(macro) F 02EA DECFSZ I2CBITS, F ;Count bits A GOTO iiout_loop_0 ;Loop for last bit CF MOVLW TAREAD ;Done with last bit 0... Set to 1 for ACK TRIS PORTA A GOTO iiout_ack ;Get ACK iiout_loop_ RLF I2CREG,F ;Shift data out, MSB first SKPC ;0->1: change A6A GOTO iiout_0 ;Output another 0! CF MOVLW TAREAD ;Set to TRIS PORTA iiout_ CLRWDT ;Clear watchdog timer USER_Q M ;*** This would be quick user code A iiout_loop_ BBC B_SCL,iiOUT_loop_12 ;Wait for clock high 007A 0725 M BTFSS B_SCL>>8,B_SCL&7 ;(macro) 007B 0A7A M GOTO iiout_loop_12 ;(macro)

21 00547 USER_Q M ;*** This would be quick user code C iiout_loop_ BBS B_SCL,iiOUT_loop_13 ;Wait for clock low 007C 0625 M BTFSC B_SCL>>8,B_SCL&7 ;(macro) 007D 0A7C M GOTO iiout_loop_13 ;(macro) E 02EA DECFSZ I2CBITS, F ;Count bits 007F 0A GOTO iiout_loop_1 ;Loop for last bit iiout_ack ;Get acknowledge A INCF I2CSUBA, F ;Next sub-address iiout_loop_a BBC B_SCL,iiOUT_loop_a2 ;Wait for clock high M BTFSS B_SCL>>8,B_SCL&7 ;(macro) A81 M GOTO iiout_loop_a2 ;(macro) BBS B_SDA,I2CWAIT ;No ACK --- wait for restart! M BTFSC B_SDA>>8,B_SDA&7 ;(macro) A11 M GOTO I2CWAIT ;(macro) ;-- prepare next character here! iiout_loop_a BBC B_SCL,NEXTOUT ;Wait for clock low - output next char! M BTFSS B_SCL>>8,B_SCL&7 ;(macro) A55 M GOTO NEXTOUT ;(macro) BBS B_SDA,iiOUT_loop_a3 ;Watch out for new start condition! M BTFSC B_SDA>>8,B_SDA&7 ;(macro) A85 M GOTO iiout_loop_a3 ;(macro) A GOTO I2CWAIT ;Stop received! 008A USER_READ ;user code to process data sent A 0A GOTO I2CWAIT ;********************************************************************** ;* Unit address received - check for valid address ;* ;**********************************************************************

22 008B ACK_UA SEB B_UA ;Flag unit address received 008B 0527 M BSF B_UA>>8,B_UA&7 ;(macro) 008C BTFSC I2CREG,0 ;Skip if data coming in SEB B_RD ;Flag - reading from slave 008D 0507 M BSF B_RD>>8,B_RD&7 ;(macro) 008E MOVF I2CREG,W ;Get address 008F 0EFE ANDLW 0FEH ;Mask direction flage before compare FD XORLW DEVICE_ADDRESS ;Device address A BNZ I2CWAIT ;Not for me! (skip rest of message) BBS B_RD,ACKloop ;Read - no secondary address M BTFSC B_RD>>8,B_RD&7 ;(macro) A47 M GOTO ACKloop ;(macro) SEB B_SA ;Next is secondary address M BSF B_SA>>8,B_SA&7 ;(macro) A GOTO ACKloop ;Yes! ACK address and continue! ;********************************************************************** ;* Secondary address received - stow it! ;* SA = 0 is converted to 128 to facilitate ID read ;********************************************************************** ACK_SA CLB B_SA ;Flag second address received M BCF B_SA>>8,B_SA&7 ;(macro) CLB B_ID M BCF B_ID>>8,B_ID&7 ;(macro) MOVFW I2CREG ;Get subaddress 009A SKPNZ ;Not SEB B_ID ;Flag - id area selected 009B 0567 M BSF B_ID>>8,B_ID&7 ;(macro) 009C MOVWF I2CSUBA ;Set subaddress 009D 0A GOTO ACKloop END MEMORY USAGE MAP ( X = Used, - = Unused) 0000 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX 0040 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX 0080 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXX C0 : X All other memory blocks unused. Program Memory Words Used: 159 Program Memory Words Free: 353 Errors : 0

23 深圳市英锐恩科技有限公司全球销售及服务网点单片机集成方案全方位解决服务商优质智能电子产品芯方案解决商联系信息 : 深圳市英锐恩科技有限公司 ENROO-TECH(SHENZHEN)CO.,LTD 中国深圳市福田区福华路嘉汇新城汇商中心 27 楼 2701 Enroo-Tech Technologies CO., Limited Light-Tech International Limited 香港新界荃灣沙咀道號科技中心 5 樓 5 室联系电话 : , , , , 联系传真 : 联系邮件 :enroo@enroo.com 公司网站 : ; Add: 深圳市福田区福华路嘉汇新城汇商中心 27 楼 2701 Tel: , Fax:

24 Warnings : 0 reported, 0 suppressed Messages : 0 reported, 0 s

AN579

AN579 深圳市英锐恩科技有限公司单片机集成方案全方位解决服务商优质智能电子产品芯方案解决商 Microchip 产品用户参考手册深圳市英锐恩科技有限公司 ENROO-TECH(SHENZHEN)CO.,LTD 中国深圳市福田区福华路嘉汇新城汇商中心 27 楼 2701 Enroo-Tech Technologies CO., Limited Light-Tech International Limited