```
; DS3231 Definition
Symbol DS3231 = $D0 ; I2C Device
Symbol DAT_A1 = $07 ; Alarm 1 Registers
Symbol DAT_A2 = $0B ; Alarm 2 Registers
Symbol CTR = $0E ; Control Register
Symbol CTR_A1IE = bit0
Symbol CTR_A2IE = bit1
Symbol CTR_INTCN = bit2
Symbol CTR_RS1 = bit3
Symbol CTR_RS2 = bit4
Symbol CTR_CONV = bit5
Symbol CTR_BBSQW = bit6
Symbol CTR_EOSC = bit7
Symbol STS = $0F ; Status Register
Symbol STS_A1IF = bit0
Symbol STS_A2IF = bit1
Symbol STS_BSY = bit2
Symbol STS_EN32K = bit3
Symbol STS_OSF = bit7
; Alarm 1
#Macro A1(x,d,h,m,s)
; Disable Alarm 1
HI2cIn CTR, (b0)
CTR_A1IE = 0
HI2cOut CTR, (b0)
; Clear Alarm 1 Flags
HI2cIn STS, (b0)
STS_A1IF = 0
HI2cOut STS, (b0)
; Set Alarm 1
b0 = x
b1 = s / 10 * 6 + s : b1 = bit0 * $80 | b1
b2 = m / 10 * 6 + m : b2 = bit1 * $80 | b2
b3 = h / 10 * 6 + h : b3 = bit2 * $80 | b3
b4 = d / 10 * 6 + d : b4 = bit3 * $80 | b4 : b4 = bit4 * $40 | b4
HI2cOut DAT_A1, (b1,b2,b3,b4)
; Enable Alarm 1
HI2cIn CTR, (b0)
CTR_A1IE = 1
CTR_INTCN = 1
HI2cOut CTR, (b0)
#EndMacro
#Define A1_EVERY_S() A1(%11111,0,0,0,0) ; per second
#Define A1_S(s) A1(%11110,0,0,0,s) ; seconds match
#Define A1_MS(m,s) A1(%11100,0,0,m,s) ; minutes and seconds match
#Define A1_HMS(h,m,s) A1(%11000,0,h,m,s) ; hours, minutes, and seconds match
#Define A1_DAY_HMS(d,h,m,s) A1(%00000,d,h,m,s) ; day, hours, minutes, and seconds match
#Define A1_DOW_HMS(w,h,m,s) A1(%10000,w,h,s,s) ; day of week, hours, minutes, and seconds match
; Alarm 2
#Macro A2(x,d,h,m)
; Disable Alarm 2
HI2cIn CTR, (b0)
CTR_A2IE = 0
HI2cOut CTR, (b0)
; Clear Alarm 2 Flags
HI2cIn STS, (b0)
STS_A2IF = 0
HI2cOut STS, (b0)
; Set Alarm 2
b0 = x
b1 = m / 10 * 6 + m : b1 = bit0 * $80 | b1
b2 = h / 10 * 6 + h : b2 = bit1 * $80 | b2
b3 = d / 10 * 6 + d : b3 = bit2 * $80 | b3 : b3 = bit3 * $40 | b3
HI2cOut DAT_A2, (b1,b2,b3)
; Enable Alarm 2
HI2cIn CTR, (b0)
CTR_A2IE = 1
CTR_INTCN = 1
HI2cOut CTR, (b0)
#EndMacro
#Define A2_EVERY_M() A2(%1111,0,0,0) ; per minute
#Define A2_M(m) A2(%1110,0,0,m) ; minutes match
#Define A2_HM(h,m) A2(%1100,0,h,m) ; hours and minutes match
#Define A2_DAY_HM(d,h,m) A2(%0000,d,h,m) ; day, hours and minutes match
#Define A2_DOW_HM(w,h,m) A2(%1000,w,h,m) ; day of week, hours and minutes match
; Example code
HI2cSetup I2CMASTER, DS3231, I2CSLOW, I2CBYTE
A1_MS(10,30) ; Alarm 1 once an hour at xx:10:30
A2_EVERY_M() ; Alarm 2 every minute
```