RTC 1307 code minimized to 1 byte & 1 nib
Falcon
Posts: 191
I want to use the DS1307 Real Time Clock in a BS2Px project but I only have a few BYTES of variable space left. I started with code I found on this fourm and slowly deleted parts that were not required including the AM-PM and 12-hour clock formatting. I can get by with 24-hour clock. All worked good at that point.
The next step is to try to make use of the Scratchpad RAM to shuffle BYTES of data around instead of having a separate BYTE for year, month, date, hour, minute and seconds. At that point it fails. See code including Get and Put commands below.
The following shows the input and displayed results with the below code:
Input Results
year 12 03:33:00
month 04 33/33/33
date 14
hours 12
mins 33
After the clock is started (with the above inputs) the last number on the second line counts up seconds, and the first number on the second line increments up when the seconds reaches 60 (so it's showing minutes.)
I suspect the error is in the subroutines that include the I2CIN & I2COUT statements.
For now, I left the seconds variable in use but I would like to remove it also if possible.
Is this approach (using only 1 BYTE) even possible?
falcon
The next step is to try to make use of the Scratchpad RAM to shuffle BYTES of data around instead of having a separate BYTE for year, month, date, hour, minute and seconds. At that point it fails. See code including Get and Put commands below.
The following shows the input and displayed results with the below code:
Input Results
year 12 03:33:00
month 04 33/33/33
date 14
hours 12
mins 33
After the clock is started (with the above inputs) the last number on the second line counts up seconds, and the first number on the second line increments up when the seconds reaches 60 (so it's showing minutes.)
I suspect the error is in the subroutines that include the I2CIN & I2COUT statements.
For now, I left the seconds variable in use but I would like to remove it also if possible.
Is this approach (using only 1 BYTE) even possible?
falcon
' {$STAMP BS2p}
' {$PBASIC 2.5}
' -----[ Program Description ]---------------------------------------------
'
' This program demonstrates the access and control of an external real-
' time-clock chip, the DS1307.
' -----[ I/O Definitions ]-------------------------------------------------
SDA PIN 0 ' I2C serial data line
SCL PIN 1 ' I2C serial clock line
LCD PIN 11
' -----[ Constants ]-------------------------------------------------------
DS1307 CON %1101 << 4
' -----[ Variables ]-------------------------------------------------------
secs VAR Byte ' DS1307 time registers
'mins VAR Byte
'hrs VAR Byte
'day VAR Byte ' weekday
'date VAR Byte ' day in month, 1 - 31
'month VAR Byte
'year VAR Byte
time VAR Byte
idx VAR Nib
' =========Define names for LCD instructions, bps=======
homeCur CON 1 'Cursor home cntl-A
bigChar CON 2 'Begin big characters cntl-B
regChar CON 3 'End big characters cntl-C
noCurs CON 4 'Make cursor invisible cntl-D
ulCurs CON 5 'Show underline cursor cntl-E
blkCurs CON 6 'Show blinking block cursor
ringBell CON 7 'Bell output cntl-G
backSp CON 8 'Backspace cntl-H
hTab CON 9 'Horizontal tab (4 col) cntl-I
curLF CON 10 'Smart linefeed cntl-J
vTab CON 11 'cursor up one line cntl-K
clrLCD CON 12 'Clear entire LCD screen cntl-L
carRet CON 13 'Carriage return cntl-M
onBkLight CON 14 'Backlight on cntl-N
offBkLight CON 15 'Backlight off cntl-O
posCmd CON 16 'Position cursor cntl-P
clrCol CON 17 'Clear column cntl-Q ?
alignRight CON 18 'Accept right-alignment data cntl-R
Esc CON 27 'Escape sequences
'TrueBaud mode for non-inverted 9600-N81 (MAX233a line driver)
'InvBaud mode for inverted, 9600-N81 (direct connect e.g. w/22k ohm)
#SELECT $STAMP
#CASE BS2, BS2E, BS2PE
TrueBaud CON 84
InvBaud CON 16468
#CASE BS2SX, BS2P
TrueBaud CON 240
InvBaud CON 16624
#CASE BS2PX
TrueBaud CON 396
InvBaud CON 16780
#ENDSELECT
' -----[ Initialization ]--------------------------------------------------
Reset:
DEBUG CLS, "Enter 'y' to set date"
SERIN 16, TrueBaud, 8000, Skip_set, [WAIT("y")]
DEBUG CLS ' Clear The DEBUG Screen
SetClock:
DEBUG CRSRXY, 0, 0, "Enter 2 dig year", CLREOL
DEBUGIN HEX2 time ' Set Year
PUT 40, time
I2COUT SDA, DS1307, 0, [time]
DEBUG CRSRXY, 12, 0, "mth", CLREOL
DEBUGIN HEX2 time ' Set Month
PUT 41, time
I2COUT SDA, DS1307, 1, [time]
DEBUG CRSRXY, 12, 0, "day", CLREOL
DEBUGIN HEX2 time ' Set Date
PUT 42, time
I2COUT SDA, DS1307, 2, [time]
'DEBUG CRSRXY, 6, 0, "week day", CLREOL
DEBUG CLS
DEBUG CRSRXY, 0, 1, CLREOL
DEBUG CRSRXY, 6, 0, "2 dig hour, 00-23", CLREOL
DEBUGIN HEX2 time ' Set Hours (24 Hour Mode)
PUT 43, time
I2COUT SDA, DS1307, 3, [time]
DEBUG CRSRXY, 12, 0, "min, 00-59", CLREOL
DEBUGIN HEX2 time ' Set Minutes
PUT 44, time
I2COUT SDA, DS1307, 4, [time]
secs = $00
GOSUB Set_Clock ' block write clock regs
' -----[ Program Code ]----------------------------------------------------
Skip_set:
DEBUG CLS,
Main:
GOSUB Get_Clock ' read DS1307
'IF secs = 128 THEN GOTO SetClock 'clock not set
GET 43, time
DEBUG CRSRXY, 0, 2, HEX2 time, ":" 'hours
GET 41, time
DEBUG CRSRXY, 3, 2, HEX2 time, ":" 'minutes correct
DEBUG CRSRXY, 6, 2, HEX2 secs, CR 'seconds
GET 44, time
DEBUG HEX2 time, "/" 'month
GET 42, time
DEBUG HEX2 time, "/" 'date
GET 40, time
DEBUG HEX2 time, CR 'year
PAUSE 100
GOTO Main
' -----[ Sub Routine Code ]----------------------------------------------------
' Do a block write to clock registers
Set_Clock:
FOR idx = 0 TO 4
I2COUT SDA, DS1307, idx, [time] ' update clock registers
NEXT
RETURN
' Do a block read from clock registers
Get_Clock:
FOR idx = 0 TO 4
I2CIN SDA, DS1307, idx, [time] ' retrieve clock registers
PUT idx + 40, time
NEXT
RETURN
Comments
second ' $00 - $59 bcd, high bit set if clock not running
minute ' $00 - $59 bcd
hour ' $00 - $23 bcd
dow ' day of week $00 - $06
date ' $00 - $31
but getClock is stopping there at 5 bytes, not reading in the month and year. That is not consistent with the data input and display section, where the year is associated with location 40.
One option for the I2C command is the SPSTR modifier:
I2CIN SDA, DS1307, 0, [SPSTR 7]
Read 7 clock registers from the DS1307 starting with seconds directly into SPRAM starting at location 0.
I may implement your suggestion. I will have to see if the DS1307 compensates for DST.
Tracy,
I finally got it worked out. I checked to see that it increments correctly to the next month and next year.
Uses only 1 byte and 1 Nib.
Thanks for your help.
falcon
' {$STAMP BS2p} ' {$PBASIC 2.5} ' -----[ Program Description ]--------------------------------------------- ' ' This program demonstrates the access and control of an external real- ' time-clock chip, the DS1307. ' -----[ I/O Definitions ]------------------------------------------------- SDA PIN 0 ' I2C serial data line SCL PIN 1 ' I2C serial clock line LCD PIN 11 ' -----[ Constants ]------------------------------------------------------- DS1307 CON %1101 << 4 ' -----[ Variables ]------------------------------------------------------- time VAR Byte idx VAR Nib ' =========Define names for LCD instructions, bps======= 'TrueBaud mode for non-inverted 9600-N81 (MAX233a line driver) 'InvBaud mode for inverted, 9600-N81 (direct connect e.g. w/22k ohm) #SELECT $STAMP #CASE BS2, BS2E, BS2PE TrueBaud CON 84 InvBaud CON 16468 #CASE BS2SX, BS2P TrueBaud CON 240 InvBaud CON 16624 #CASE BS2PX TrueBaud CON 396 InvBaud CON 16780 #ENDSELECT ' -----[ Initialization ]-------------------------------------------------- Reset: DEBUG CLS, "Enter 'y' to set date" SERIN 16, TrueBaud, 8000, Skip_set, [WAIT("y")] DEBUG CLS ' Clear The DEBUG Screen SetClock: DEBUG CRSRXY, 0, 0, "Enter 2 dig year", CLREOL DEBUGIN HEX2 time ' Set Year 45 PUT 46, time I2COUT SDA, DS1307, 0, [time] DEBUG CRSRXY, 12, 0, "mth", CLREOL DEBUGIN HEX2 time ' Set Month 43 PUT 45, time I2COUT SDA, DS1307, 1, [time] DEBUG CRSRXY, 12, 0, "day", CLREOL DEBUGIN HEX2 time ' Set Date 44 PUT 44, time I2COUT SDA, DS1307, 2, [time] DEBUG CRSRXY, 6, 0, "2 dig hour, 00-23", CLREOL DEBUGIN HEX2 time ' Set Hours 42 PUT 42, time I2COUT SDA, DS1307, 3, [time] DEBUG CRSRXY, 12, 0, "min, 00-59", CLREOL DEBUGIN HEX2 time ' Set Minutes 41 PUT 41, time I2COUT SDA, DS1307, 4, [time] ' Set Seconds 40 time = $00 ' Set Seconds 40 PUT 40, time I2COUT SDA, DS1307, 5, [time] GOSUB Set_Clock ' block write clock regs ' -----[ Program Code ]---------------------------------------------------- Skip_set: DEBUG CLS start: GOSUB Get_Clock ' read DS1307 GET 42, time DEBUG CRSRXY, 0, 2, HEX2 time, ":" 'hours GET 41, time DEBUG CRSRXY, 3, 2, HEX2 time, ":" 'minutes GET 40, time DEBUG CRSRXY, 6, 2, HEX2 time, CR 'seconds GET 45, time DEBUG HEX2 time, "/" 'month GET 44, time DEBUG HEX2 time, "/" 'date GET 46, time DEBUG HEX2 time, CR 'year PAUSE 100 GOTO start ' -----[ Sub Routine Code ]---------------------------------------------------- ' Do a block write to clock registers Set_Clock: FOR idx = 0 TO 6 GET idx + 40, time I2COUT SDA, DS1307, idx, [time] ' update clock registers NEXT RETURN ' Do a block read from clock registers Get_Clock: FOR idx = 0 TO 6 I2CIN SDA, DS1307, idx, [time] ' retrieve clock registers PUT idx + 40, time NEXT RETURN