93c46 Eeprom Writing/reading Help

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I WAS AT THIS Thread just a minute ago and i wish i knew if dark solved his problem.
http://www.picbasic.co.uk/forum/showthread.php?t=1214

93c46 datasheet:
http://leonardo.caltech.edu/~ee5x/ee.../hw6/93c46.pdf

i have the same problem, but i dont know whether its my reading or writing that is flawed. I am trying to write 3 different byte sized variables to the 93c46. i have attached a pic that shows how it is all connected. I dont think that there are any pull up resistors on the CLK or CS line, not sure if this is a problem. I simply need someone to correct my subs.

here are my eeread and eewrite subs.

include "modedefs.bas"
DEFINE SHIFT_PAUSEUS 500

CS var PORTB.1 ' Chip select pin
SCK var PORTB.2 ' Clock pin
SI var PORTC.6 ' Data in pin
SO var PORTC.7 ' Data out pin

B0 var byte '<------- data to be written
addr var BYTE '<------ eeprom memory location 1,2,3

d var byte
t var byte
ed var byte

ADCON1=7 ' set all analog pins to digital
TRISA=%011000 'PORT A
TRISB=%11110001 'PORT B
TRISC=%10100000 'PORT C

eeread:

for addr = 1 to 3 'eeprom address

CS = 1
Shiftout SI, SCK, MSBFIRST, [%110\3, addr\6]
Shiftin SO, SCK, MSBPOST, [B0]
CS=0

if addr = 1 then
d = B0
endif

if addr = 2 then
t = B0
endif

if addr = 3 then
ED = B0
endif

pause 10
next addr
return

ewrite:
for addr = 1 to 3

if addr = 1 then
B0 = D
endif

if addr = 2 then
B0 = T
endif

if addr = 3 then
B0 = ED
endif

CS = 1 ' Enable serial EEPROM
Shiftout SI, SCK, MSBFIRST, [%10011\5, 0\7] ' Send write enable command
CS = 0

PAUSE 10

CS = 1 ' Enable
Shiftout SI, SCK, MSBFIRST, [%101\3, addr\6, B0] ' Send address and data
CS = 0
pause 10
next addr
Return

the ports that the CLK and CS are connected to (portb.1 and portb.2) have programmable weak internal resistors if necesary (Option_reg.7) BUT SI and SO dont. they are on port C.6 and c.7

As i remind some PM Darkman solved his problem and much more.
FIRTS of all add

Code:

LOW CS pause 50

before your main loop.
those are working. Just change your Shiftin/Shiftout statements

Code:

eeread: CS = 1 ' Enable serial EEPROM Shiftout DI, CLK, MSBFIRST, [%110\3, addr\6] Shiftin DO, CLK, MSBPOST, [B0] ' Read data CS = 0 ' Disable ' Subroutine to write data at addr in serial EEPROM eewrite: CS = 1 ' Enable serial EEPROM Shiftout DI, CLK, MSBFIRST, [%10011, 0\4] ' Send write enable command and dummy clocks pause 10 CS = 0 ' Disable CS = 1 ' Enable serial EEPROM Shiftout DI, CLK, MSBFIRST, [%101\3 ,addr\6,B0] pause 10 CS = 0 ' Disable

You don't need any resistor

thanks for reply

yo dude, thanks alot for the reply. ill try it out tommorow, 2.40 am right now. and let ya know if it worked for me. i have been bashing my brain trying to understand how to use the instructions.

It Works!

the code you gave me works with just a minor tweak. i had to make the eeproms address (addr) increment by 2. so i used addr= 0, addr=2, addr=4,...etc..

heres the working code. refer to my 1st post for the port settings,variables, n stuff.

eeread:

for addr = 0 to 5 step 2 'eeprom address 0

'read from eeprom
CS = 1
Shiftout SI, SCK, MSBFIRST, [%110\3, addr\6]
Shiftin SO, SCK, MSBPOST, [B0]
cs=0 ' Disable

if addr = 0 then
d = B0
endif

if addr = 2 then
t = B0
endif

if addr = 4 then
ED = B0
endif

pause 10
next addr
return

eewrite:
for addr = 0 to 5 step 2

if addr = 0 then
B0 = D
endif

if addr = 2 then
B0 = T
endif

if addr = 4 then
B0 = ED
endif

CS = 1 ' Enable serial EEPROM
Shiftout SI, SCK, MSBFIRST, [%10011, 0\4] ' Send write enable command
CS = 0

pause 10

CS = 1 ' Enable
Shiftout SI, SCK, MSBFIRST, [%101\3, addr\6, B0] ' Send address and data
CS = 0
pause 10
next addr
Return

end

thank you SO much!!!