Interfacing X24C44/45 NOVRAMs 8051 Microcontrollers Xicor reached

The Datasheet Archive - 100 Million Datasheets from 7500 Manufacturers.

Interfacing X24C44/45 NOVRAMs 8051 Microcontrollers Xicor reached

Datasheet Thumbnail

Top Searches for this datasheet

AN15
Interfacing X24C44/45 NOVRAMs 8051 Microcontrollers
Xicor reached toll free 1-800-2588864, (408) area code internationally 1-408-943-0655. Xicor's will support 19.2K baud rate modem parity, words, stop bit, local echo). These listings found INTEL (Special Interest Group). Xicor application notes also available through Xicor's FaxBack system (408) 954-1627.
P0.0 P0.1 P0.2 P0.3 P0.4 P0.5 P0.6 P0.7 P2.0 P2.1 P2.2 P2.3 P2.4 P2.5 P2.6 P2.7 PSEN ALE/P 8051 EA/VP RESET INT0 INT1 P1.0 P1.1 P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 RECALL STORE X24C44
Figure Typical hardware connection interfacing X24C44 8051 microcontrollers
Xicor, Inc. 1511 Buckeye Drive Milpitas, 95035 (408) 432-8888
AN15-1
Xicor THIS CODE DESIGNED DEMONSTRATE 24C44 COULD INTERFACED 8031 MICROCONTROLLER. INTERFACE USES LINES FROM PORT (P1.7, P1.6, P1.5) COMMUNICATE. PINS 24C44 TIED TOGETHER WHICH ALLOWS LESS PORT LINE USED. CODE SHOWN DEMONSTRATES RCL, WREN, READ, WRITE, STORE INSTRUCTIONS. REMAINING INSTRUCTIONS (WRDS ENAS) ISSUED USING SAME ROUTINE OTHER NON-DATA INSTRUCTIONS. PROGRAM ISSUES SEQUENCE INSTRUCTIONS READ CONTENTS ADDRESS STORES SAME VALUE ADDRESS SEQUENCE INSTRUCTIONS FOLLOWS SETS PREVIOUS RECALL LATCH WREN SETS WRITE ENABLE LATCH READ DATA FROM ADDRESS READ WRITE DATA READ DURING STEP WRITTEN ADDRESS RAM'S CONTENTS TRANSFERED EEPROM DATA TRANSFER PERFORMED WITH MOST SIGNIFICANT FIRST. THIS CODE WITH X24C45 NOVRAM, YOU'LL NEED ENABLE AUTOSTORE FUNCTION SENDING ENAS INSTRUCTION SIMILAR MANNER, OTHERWISE ENAS USED X24C44. WRDS ENAS WRITE WREN READ DATAHI DATALO ADDR COUNT INST P1.5 P1.6 P1.7 GENERATED PORT GENERATED PORT GENERATED PORT RESET WRITE ENABLE LATCH TRANSFERS FROM EEPROM PLACES PART INTO POWER DOWN MODE WRITE WRITE ENABLE LATCH TRANSFERS FROM EEPROM RAM, RESETS WRITE ENABLE LATCH READ REGISTER WHERE HIGH ORDER DATA STORED REGISTER WHERE ORDER DATA STORED REGISTER WHERE PART ADDRESS STORED LOOP COUNT VARIABLE REGISTER WHERE INSTRUCTION STORED
AN15
RESET VECTOR BEGINNING PROGRAM CODE LJMP 0000H BEGIN RESET VECTORS THIS LOCATION
;***************************** START PROGRAM EXECUTION ;***************************** 0100H BEGINNING PROGRAM CODE
AN15-2
Xicor BEGIN: LCALL LCALL LCALL LCALL LCALL LCALL SP,#60H A,#RCL INST,A CEHIGH OUTBYT CELOW A,#WREN INST,A CEHIGH OUTBYT CELOW INITIALIZE STACK POINTER INITIALIZE CONTROL SIGNALS
AN15
PERFORM RECALL RECALL LATCH
PERFORM WRITE ENABLE WRITE ENABLE LATCH
A,#05H ADDR,A LCALL RDWRD A,#09H ADDR,A LCALL WRWRD LCALL LCALL LCALL DONE: LJMP A,#STO INST,A CEHIGH OUTBYT CELOW DONE
READ CONTENTS ADDRESS VALUE READ WILL STORED DATALO DATAHI WRITE DATA JUST READ INTO ADDRESS
PERFORM STORE OPERATION
LOOP UNTIL RESET
WRITE WORD SPECIFIED DATAHI DATALO. ADDRESS WRITTEN SPECIFIED ADDR. WRWRD: LCALL LCALL LCALL LCALL LCALL CEHIGH A,ADDR A,#WRITE INST,A OUTBYT A,DATAHI INST,A OUTBYT A,DATALO INST,A OUTBYT CELOW WRITE VALUE DATAHI+LO INTO LOCATION SPECIFIED ADDR JUSTIFY ADDRESS INSTRUCTION
MASK WRITE INSTRUCTION SEND WRITE INSTRUCTION
SEND UPPER BYTE DATA
SEND LOWER BYTE DATA
AN15-3
Xicor READ WORD ADDRESS SPECIFIED ADDR. DATA WILL STORED DATALO DATAHI. RDWRD: LCALL LCALL SETB LCALL LCALL DJNZ LCALL CEHIGH A,ADDR A,#READ INST,A SEND7 CLOCK COUNT,#10H C,DIO A,DATALO DATALO,A A,DATAHI DATAHI,A CLOCK COUNT,BITX CELOW READ ADDRESS SPECIFIED ADDR JUSTIFY ADDRESS READ
AN15
MASK READ INSTRUCTION SEND BITS READ INSTRUCTION SEND EIGHTH CLOCK PULSE READ INSTRUCTION PREPARE SHIFT BITS READ VALUE SHIFT DATA FROM INTO DATALO DATAHI
BITX: NO1:
SEND CLOCK PULSE LOOP WHILE READING DATA
SEND DATA PART. DATA SENT LOCATED INST. SEND7: OUTBYT: LOOPO: SJMP LCALL DJNZ COUNT,#07H LOOPO COUNT,#08H A,INST INST,A DIO,C CLOCK COUNT,LOOPO SHIFT BITS READ INSTRUCTION PREPARE SHIFT BITS FIND DATA SHIFT
SEND CLOCK SIGNAL LOOP WHILE STILL SHIFTING DATA
;**************** BRING HIGH ;**************** CEHIGH: SETB BRING HIGH
;*************** BRING ;*************** CELOW: BRING
AN15-4
Xicor ;*********************** ISSUE CLOCK PULSE. ;*********************** CLOCK: SETB SEND CLOCK PULSE (BRING HIGH) BRING
AN15
AN15-5

Interfacing X24C44/45 NOVRAMs 8051 Microcontrollers Xicor reached

Top Searches for this datasheet

Other recent searches