DS-1307RTC-eeprom.TXT

\ 24c32 I2C 32Kb EEPROM chip single byte write and read.
\ This chip is often found on same small board with DS1307 RTC! 🙂
\ $50 is the I2C number/address used by my 24c32 32Kb chip 
\ OBS: Some chips, e.g. Atmel, use adr + 1 (51) for Read, and 50 for Write!
\ My chip use same addr. for both read and write!
\ Max addr. for a single byte write/read: 7FFF !
\ Jan Langevaad  28-February-2022

base @
hex
WIRE

: 24c32writebyte		\ DATAbyte ADDR16bits(0...7FFF)  --- 

	 50 	Wire.beginTransmission	\ start $50 write drop	 
	 dup 
	 100 /		\ get MSB 
	 TimeBuff 9 +	c!
	 TimeBuff 9 +	1 Wire.write drop \ adr MSB in EEPROM 

	 ff and		\ get LSB 
	 TimeBuff 9 +	c!
	 TimeBuff 9 +	1 Wire.write drop \ adr MSB in EEPROM 
 
	 TimeBuff 9 +	c!
	 TimeBuff 9 +	1 Wire.write drop \ DataByte to EEPROM 

	1 	Wire.endTransmission  drop \ 1=StopOption --- Return   Drop(0= ok 1..4 see doc!)
; 

: 24c32readbyte			\ ADDR16bits(0...7FFF) --- databyte 

	50 	Wire.beginTransmission
	dup 
	100 /			\ get MSB 
	TimeBuff 9 + c!
	TimeBuff 9 +	
	1 	Wire.write drop 	\ adr MSB in EEPROM 

	ff and			\ get LSB 
	TimeBuff 9 + c!
	TimeBuff 9 +	
	1 	Wire.write drop \ adr MSB in EEPROM  
	0 Wire.endTransmission  drop \ --- 0 = cont. option, drop return 0= ok 1..4 see d

	50 1 -1  	Wire.requestFrom drop
	Wire.Available drop	 	\ --- # 		bytes to read
	Wire.Read		\ --- RamDataByte
; 

FORTH
BASE !

\ EOF