' ****************************************************************
' * File:  uk_gmb_rtc.pbas  -  Ver. 1.1                          *
' * Compiler:  mikroBasic for PIC by mikroElektronica            *
' * IDE: mikroBasic for PIC by mikroElektronica                  *
' * Compiler Version: 1.1.5.0                                    *
' * Boards: GMM 4620 + GMB HR168                                 *
' *   GRIFO(R)   via Dell'Artigiano 8/6                          *
' *   40016 S. Giorgio di Piano (BO)                             *
' *   Tel. +39 051 892052                   Fax. +39 051 893661  *
' *   http://www.grifo.com                  http://www.grifo.it  *
' * by Graziano Gaiba                              16.02.05      *
' ****************************************************************
'
' GMM 4620 is provided with on board Real Time Clock, RTC, backed
' through the on board Lithium battery, disconnectable.
' Such component can be used to schedule sequences of operations
' or to create a timestamp for certain events.
' Interface between RTC and microcontroller is I2C BUS.
' functionality, both to get and to set time, through a set of
' widely commented functions.
' Such functions are charged to communicate to the component and
' to show time and date.

'
' Rel 1.1 - by Graziano Gaiba
' Demo program of buffered I/O peripherals of GMB HR168 driven by
' Mini Module GMM 4620
'
'
' ******************** Compiler definitions **********************
'
program uk_gmb_rtc
'
' ******************* Constants declaration **********************
'
const RTCSLA = $A0
const ASC_y  = $79
const ASC_yU = $59
'
' ******************** Variables declaration *********************
'
' Generic variables
dim i as byte
dim s as string[2]
'
' Used by RTC management
dim rtc_year as byte
dim rtc_month as byte
dim rtc_weekday as byte
dim rtc_day as byte
dim rtc_hour as byte
dim rtc_minute as byte
dim rtc_second as byte
'
'
' **************** Procedures definition ******************
'
'
' CPU and signals directions initialization
sub procedure Init_cpu
' Initialize portc for hardware I2C BUS peripheral
    trisc.3 = 0
    trisc.4 = 0
    portc.3 = 1
    portc.4 = 1
    '
    ADCON1=$0f        ' Imposta come I/O digitale i pin AN0..12
    CMCON=$07         ' Imposta come I/O digitale RA0..4
' Optocoupled Inputs of CN1 are:
' IN1-1 <-> RA0
' IN2-1 <-> RA1
' IN3-1 <-> RB0
' IN4-1 <-> RB1
' IN5-1 <-> RA4
' IN6-1 <-> RC0
' IN7-1 <-> RC1
' IN8-1 <-> RC5
    trisa.0=1
    trisa.1=1
    trisa.4=1
    trisb.0=1
    trisb.1=1
    trisc.0=1
    trisc.1=1
    trisc.5=1
' Optocoupled Inputs of CN2 are:
' IN1-2 <-> RD0
' IN2-2 <-> RD1
' IN3-2 <-> RD2
' IN4-2 <-> RD3
' IN5-2 <-> RD4
' IN6-2 <-> RD5
' IN7-2 <-> RD6
' IN8-2 <-> RD7
    trisd=$ff
' Relay outputs of CN3 are:
' OUT A1 <-> RB4
' OUT A2 <-> RB5
' OUT B1 <-> RB6
' OUT B2 <-> RB7
' OUT C1 <-> RB3
' OUT C2 <-> RB2
    trisb=trisb and $03
' Relay outputs of CN4 are:
' OUT D1 <-> RA3
' OUT D2 <-> RC2 (J10 in position 3-4)
    trisa.3=0
    trisc.2=0
    ' Initialize module USART (8 bit, 19200 baud rate,
    ' no parity)
    Usart_init(19200)
end sub
'
'
' Send a string of characters to the serial port
sub procedure print_USART(dim byref txt as char[255])
    dim i as byte
    dim l as byte

    l = txt[0]
    for i = 1 to l
        USART_Write(txt[i])
    next i
end sub
'
'
' Send CR + LF
sub procedure print_CRLF
    USART_Write(10)
    USART_Write(13)
end sub
'
'
' Clear screen, sending 25 times CR + LF.
sub procedure clrscr
    for i = 0 to 24
    print_CRLF
    next i
end sub
'
'
' Asks for a key press
sub procedure wait_key
    dim c as byte

    print_usart("Press a key...")
    do
        nop
    loop until USART_Data_Ready = 1
    c = USART_Read
end sub
'
'
' Procedure to set the status of the relays on connectors CN3 and CN4.
' According to the bits of port_val, each relay is turned ON
' (contact closed) or OFF (contact open).
' Bits of port_val have this meanging:
' -- CN3
' port_val.0 drives relay OUT A1
' port_val.1 drives relay OUT A2
' port_val.2 drives relay OUT B1
' port_val.3 drives relay OUT B2
' port_val.4 drives relay OUT C1
' port_val.5 drives relay OUT C2
' -- CN4
' port_val.6 drives relay OUT D1
' port_val.7 drives relay OUT D2
'
' Each bit has the following meaning:
'   bit              Meaning
'    0    Relay turned OFF (contact open)
'    1    Relay turned ON (contact closed)
sub procedure set_relays(dim port_val as byte)
' Relays are driven in complemented logic, so port_val must be
' complemented too
    port_val=port_val xor $ff
    portb.4=port_val.0
    portb.5=port_val.1
    portb.6=port_val.2
    portb.7=port_val.3
    portb.3=port_val.4
    portb.2=port_val.5

    porta.3=port_val.6

    portc.2=port_val.7
end sub
'
'
' Indicates that an expected acknowledge has not been received.
sub procedure I2CBUSNotAck
    print_USART("Acknowledge not received.")
    print_crlf
' Disables I2CBUS
    sspcon1.5=0
end sub
'
'
' Read one byte from device whose slave address is indicated in variable
' i2c_slave and whose address is specified in variable i2c_addr.
' Data read is returned.
sub function I2CBUSReadByte(dim i2c_slave as byte, dim i2c_addr as byte) as byte
    dim b as byte

    sspcon1.5 = 0
    sspcon1.5 = 1
'
' Generates I2CBUS Start.
    I2C_start
' Send Slave Address
    if I2C_wr(i2c_slave) <> 0 then
' If acknowledge not received, signal an error
        I2CBUSNotAck
    end if
' Send address
    if I2C_wr(i2c_addr) <> 0 then
' If acknowledge not received, signal an error
        I2CBUSNotAck
    end if
' Generates repeated I2CBUS Start.
    I2C_Repeated_Start
' Send Slave Address for reading
    if I2C_wr(i2c_slave or $01)  <> 0 then
' If acknowledge not received, signal an error
         I2CBUSNotAck
    end if
' Get data and Send NOT acknowledge
    b = I2C_Rd(0)
' Generate stop
    I2C_Stop

    Result = b
end sub
'
'
' Write one byte to device whose slave address is indicated in variable
' i2c_slave and whose address is specified in variable i2c_addr.
' Data to write must be in variable i2c_data.
sub procedure I2CBUSWriteByte(dim i2c_slave as byte, dim i2c_addr as byte,
                              dim i2c_data as byte)
    sspcon1.5 = 0
    sspcon1.5 = 1
'
' Generates I2CBUS Start.
    I2C_start
' Send Slave Address for writing
    if I2C_wr(i2c_slave) <> 0 then
' If acknowledge not received, signal an error
        I2CBUSNotAck
    end if
' Send address
    if I2C_wr(i2c_addr) <> 0 then
' If acknowledge not received, signal an error
        I2CBUSNotAck
    end if
' Send data
    if I2C_wr(i2c_data) <> 0 then
' If acknowledge not received, signal an error
        I2CBUSNotAck
    end if
' Generates stop
    I2C_Stop
end sub
'
'
' Inputs a positive decimal vale of up to five digits.
' Input parameter is number of digits, it returns a word
' containing the value input by te user.
' It can manage backspace (ASCII 08) and accepts digits from
' '0' to '9'.
' It sends a bell character (ASCII 07) when receives a character
' not acceptable for input, or user tries to input or delete out
' of possible range.
sub function inputDEC(dim n_char as byte) as word
    dim str_input as byte[6]
    dim idx as byte
    dim chr_input as byte
    dim pow_of_10 as word[5]
    dim value as word

    pow_of_10[1] = 1
    pow_of_10[2] = 10
    pow_of_10[3] = 100
    pow_of_10[4] = 1000
    ' Index must start from 1
    idx = 1
    Inc(n_char)
    ' No character in input
    chr_input = 0
    ' Starting value
    value = 0
    ' Loop until CR is received
    while chr_input <> 13
        ' If a data is ready
        if usart_data_ready = 1 then
            ' Read it
            chr_input = USART_Read
            ' If backspace (ASCII BS)
            if chr_input = 8 then
                ' and buffer is not empty
                if idx > 1 then
                    ' Send data read
                    USART_Write(chr_input)
                    ' Delete character
                    USART_Write(32)
                    USART_Write(chr_input)
                    ' delete last input data
                    Dec(idx)
                else
                    ' Bell to indicate an error
                    USART_Write(7)
                end if
            end if
            ' If CR received, elaborate the value and return it
            if chr_input = 13 then
                n_char = 0
                while idx > 1
                    Dec(idx)
                    Inc(n_char)
                    value = value + (str_input[n_char] - 48) * pow_of_10[idx]
                wend
            else
                ' If character can be input
                if idx < n_char then
                    ' If data received is in valid range:
                    ' 0..9
                    if (chr_input >= 48) or(chr_input <= 57) then
                        ' Send data read
                        USART_Write(chr_input)
                        ' Store it in input buffer
                        str_input[idx] = chr_input
                        ' Point to next position
                        Inc(idx)
                    end if
                else
                    ' Bell to indicate an error
                    USART_Write(7)
                end if
            end if
        end if
    wend
    print_CRLF
    Result = value
end sub
'
'
' Sets date and time on RTC I2C BUS PCF8583
sub procedure set_rtc(dim rtc_weekday as byte,
                      dim rtc_day as byte,
                      dim rtc_month as byte,
                      dim rtc_year as byte,
                      dim rtc_hour as byte,
                      dim rtc_minute as byte,
                      dim rtc_second as byte)

    dim dummy as byte

    ' Stop RTC
    I2CBUSWriteByte(RTCSLA,$0,$84)
    ' Set hundres of seconds
    i2cbuswritebyte(RTCSLA,$1,$0)
    ' Set seconds
    dummy = Dec2Bcd(rtc_second)
    i2cbuswritebyte(RTCSLA,$2,dummy)
    ' Set minutes
    dummy = Dec2Bcd(rtc_minute)
    i2cbuswritebyte(RTCSLA,$3,dummy)
    ' Set hours
    dummy = Dec2Bcd(rtc_hour)
    i2cbuswritebyte(RTCSLA,$4,dummy)
    ' Set day and set year = 0
    dummy = Dec2Bcd(rtc_day)
    i2cbuswritebyte(RTCSLA,$5,dummy)
    ' Set month and weekday
    dummy = Dec2Bcd(rtc_month)
    dummy = dummy or (rtc_weekday << 5)
    i2cbuswritebyte(RTCSLA,$6,dummy)
    ' Set timer mode
    i2cbuswritebyte(RTCSLA,$7,0)
    ' Start RTC
    i2cbuswritebyte(RTCSLA,$0,0)
    ' Save year offset
    i2cbuswritebyte(RTCSLA,$ff,rtc_year)
end sub
'
'
' Gets date and time from RTC I2C BUS PCF8583
sub procedure get_rtc(dim byref rtc_weekday as byte,
                      dim byref rtc_day as byte,
                      dim byref rtc_month as byte,
                      dim byref rtc_year as byte,
                      dim byref rtc_hour as byte,
                      dim byref rtc_minute as byte,
                      dim byref rtc_second as byte)

    dim dummy as byte

    ' Read and calculate seconds
    rtc_second = Bcd2Dec(i2cbusreadbyte(RTCSLA, $2))
    ' Read and calculate minutes
    rtc_minute = Bcd2Dec(i2cbusreadbyte(RTCSLA, $3))
    ' Read and calculate hours
    rtc_hour = Bcd2Dec(i2cbusreadbyte(RTCSLA, $4))
    ' Read and calculate day and year
    dummy = i2cbusreadbyte(RTCSLA, $5)
    rtc_year = (dummy and $c0) >> 6
    dummy = dummy and $3f
    rtc_day = Bcd2Dec(dummy)
    ' Read and calculate weekday and month
    dummy = i2cbusreadbyte(RTCSLA, $6)
    rtc_weekday = (dummy and $e0) >> 5
    dummy = dummy and $1f
    rtc_month = Bcd2Dec(dummy)
    ' Calculate year in the range 00..99
    ' Year offset is in location $FF of PCF internal SRAM.
    ' This location is reserved.
    dummy = i2cbusreadbyte(RTCSLA, $ff)
    rtc_year = (dummy + rtc_year) mod 100
end sub
'
'************************** Main Program *******************************
'
main:
    '
    Init_cpu
    ' Turn OFF relays
    set_relays(0)
    ' Initialize hardware I2C BUS peripheral
    I2C_init(100000)
for_ever:
    clrscr
    print_USART("I2C BUS RTC demo Rel 1.1 for GMM 4620 rel 120304 and GMB HR168 rel 110104")
    print_CRLF
    print_CRLF
    print_USART("Time and date stored in I2C BUS RTC module is continuously visualized")
    print_CRLF
    print_USART("Do you want to set RTC (y/n)? ")
    do
        nop
    loop until USART_Data_Ready = 1
    i = USART_Read
    USART_Write(i)
    if (i = ASC_y) or (i = ASC_Y) then
        print_CRLF
        print_CRLF
        print_USART("Week day (0 is Sunday, 1 is Monday, .. , 6 is Saturday): ")
        rtc_weekday = inputDEC(1)
        print_USART("Day: ")
        rtc_day = inputDEC(2)
        print_USART("Month: ")
        rtc_month = inputDEC(2)
        print_USART("Year: 20")
        rtc_year = inputDEC(2)
        print_USART("Hour: ")
        rtc_hour = inputDEC(2)
        print_USART("Minute: ")
        rtc_minute = inputDEC(2)
        print_USART("Second: ")
        rtc_second = inputDEC(2)
        print_CRLF
        set_rtc(rtc_weekday,rtc_day,rtc_month,rtc_year,rtc_hour,
                rtc_minute,rtc_second)
    end if

    print_CRLF
vis_rtc_loop:
    get_rtc(rtc_weekday,rtc_day,rtc_month,rtc_year,rtc_hour,
            rtc_minute,rtc_second)
    select case rtc_weekday
      case 0
        print_USART("Sunday    ")
      case 1
        print_USART("Monday    ")
      case 2
        print_USART("Tuesday   ")
      case 3
        print_USART("Wednesday ")
      case 4
        print_USART("Thursday  ")
      case 5
        print_USART("Friday    ")
      case 6
        print_USART("Saturday  ")
    end select
    ' Print day
    ByteToStr(rtc_day,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    print_USART(".")
    ' Print month
    ByteToStr(rtc_month,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    print_USART(".20")
    ' Print year
    ByteToStr(rtc_year,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    print_USART("  ")
    ' Print hour
    ByteToStr(rtc_hour,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    print_USART(":")
    ' Print minute
    ByteToStr(rtc_minute,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    print_USART(".")
    ' Print second
    ByteToStr(rtc_second,s)
    if length(s) = 1 then
        print_USART("0")
    end if
    print_USART(s)
    USART_Write(13)
    
    goto vis_rtc_loop

    goto for_ever
end.