' ********************************************************************** ' ** Program: k51ppie.BAS - Version : 1.1 - 28 January 2004 ** ' ** Compiler : Bascom AVR IDE - LIB 1.11.7.4 ** ' ** Scheda : K51-AVR driven by GMB HR84 and GMM AM08 ** ' ** Society: grifo(r) ITALIAN TECHNOLOGY ** ' ** Via Dell' Artigiano 8/6 40016 San Giorgio di Piano (BO) ** ' ** Tel.+39 051 892 052 Fax +39 051 893 661 ** ' ** http://www.grifo.com http://www.grifo.it ** ' ** sales@grifo.it tech@grifo.it grifo@grifo.it ** ' ** ** ' ** Written by: Graziano Gaiba ** ' ********************************************************************** ' ' This demo allows to drive an I2C BUS peripheral on board of K51-AVR, PCF8574, ' through mini-BLOCK module GMB HR84 and grifo(r) mini module. ' PCF 8574 is an I/O expander that allows to drive 8 TTL digital lines, both as ' input and as output, all the operations of read and write are performed ' through synchronous serial interface I2C BUS. ' This demo acquire the status of eight TTL digital lines, and shows it on the ' 7 segments display of K51-AVR, near the characters 'in'. ' ' ' 28.01.04 - Rel 1.1 By Graziano Gaiba per GMM AM08 ' ' Compiled file is smaller than 2048 bytes, so it can becompliled with free ' demo of BASCOM AVR. ' ' ' !!!!!!!!!!!!!!!!!!!!!!!!!!! IMPORTANT !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ' In menu Options | Compiler | Chip, set: ' ' Chip: M8 ' HW Stack: at least 64 ' Soft Stack: at least 32 ' Framesize: at least 64 ' ' ' ****************** Compiler directives ************************** ' $regfile = "m8def.dat" $crystal = 7372800 $baud = 19200 Config Sda = Portc.4 ' I2C serial DATA Config Scl = Portc.5 ' I2C serial CLK ' '********************* Constants declaration *************************** ' Const Saa1064 = &H38 ' Slave address SAA1064 Const Wsaa1064 = &H70 ' Slave address SAA1064 in Write Const Rsaa1064 = &H71 ' Slave address SAA1064 in Read '****************** Addresses list for Saa1064 ************************* Const Ctb = 0 ' Address Control byte Const Dig1 = 1 ' Address Digit 1 Const Dig2 = 2 ' Address Digit 2 Const Dig3 = 3 ' Address Digit 3 Const Dig4 = 4 ' Address Digit 4 ' ********************************************************************** ' Comment the declaration of the component not used, uncomment the other ' declaration ' 'Const Pcf8574 = &H3C ' Slave address PCF8574A 'Const Wpcf8574 = &H78 ' Slave address PCF8574A in Write 'Const Rpcf8574 = &H79 ' Slave address PCF8574A in Read Const Pcf8574 = &H24 ' Slave address PCF8574P Const Wpcf8574 = &H48 ' Slave address PCF8574P in Write Const Rpcf8574 = &H49 ' Slave address PCF8574P in Read ' '*********************** Variables declaration ************************* ' ' Value read from PCF8574 Dim Dato As Byte ' Number to send to 7-segments display Dim Cifh As Byte ' Most significant nibble Dim Cifl As Byte ' Least significant nibble ' '********************* Procedures declaration ************************** ' Declare Sub Iniz() ' Peripherals initialization Declare Sub Cifre(byval Valore As Byte ) ' converts a number in 2 HEX figures Declare Function Digit(byval Dig As Byte ) As Byte ' Converts a number in range ' 0-F in 7 segments Declare Sub Vis_num(byval N1 As Byte) ' Shows a byte in HEX ' '*************************** Main program ****************************** ' Main: Print Chr(12) Print "Demo input of 8 TTL signals of PCF8574." Print Print "7 segments displays show the value read." Call Iniz() ' initializations Do I2creceive Rpcf8574 , Dato ' read status of 8 inputs of PCF8574 Call Vis_num(dato) ' show byte in HEX Loop End ' '**************************** Program end ****************************** ' ' '**************************** Procedures ******************************* ' ' ' ********************** Peripherals initialization ******************** ' This procedure performs all the system initializations. ' Parameters: ' Input : nothing ' Output : nothing ' ********************************************************************** ' Sub Iniz() ' Inizializzazione periferiche Local Valore As Byte Do I2creceive Rsaa1064 , Valore ' Read the status register Loop Until Valore = 0 ' Wait for SAA1064 to turn on I2cstart ' Start sequence for I2CBUS I2cwbyte Wsaa1064 ' Communicate the Slave address I2cwbyte Ctb ' Point to control register I2cwbyte &B00100111 ' bit0 =1 dynamic mode ' bit1 =1 digit 1+3 not blanked ' bit2 =1 digit 2+4 not blanked ' bit3 =0 no test segment ' bit4 =0 no 3mA segment current ' bit5 =1 6mA segment current ' bit6 =0 no 12mA segment current ' bit7 =0 indifferent I2cwbyte 48 ' set DY1 "I" I2cwbyte 84 ' set DY2 "n" I2cwbyte 0 ' set DY3 off I2cwbyte 0 ' set DY4 off I2cstop End Sub ' ' ' ******** Converts a figure in range from 0 to F in 7 segments ******** ' This procedure converts a figure in range from 0 to F in 7 segments ' format, if value is greater than F the display is off. ' Parameters: ' Input : dig as byte, value in the range from 0 to F ' Outout : byte, value in 7 segments format. ' ********************************************************************** ' Function Digit(byval Dig As Byte ) As Byte ' Converts a number in range Local Valore As Byte ' 0-F in 7 segments If Dig < 16 Then ' if number is lower than 16 Valore = Lookup(dig , Tab_7seg) ' read value from table Else Valore = 0 ' if = 16 or greater reset End If Digit = Valore End Function ' ' ' ***************** Converte 1 byte in due cifre HEX ******************** ' This procedure converts 1 byte in range from 0 to 255 in two 4 bits ' hexadecimal figures. ' Parameters: ' Input : Valore as byte, value in the range from 0 to 255 ' Output : Cifh as byte, figure of high nibble ' Cifl as byte, figure of low nibble ' ************************************************************************ ' Sub Cifre(valore As Byte) ' converts a number in two HEX figures Cifh = Valore And &HF0 ' mask 4 high bits Cifh = Cifh / 16 ' shift to low the 4 high bits Cifl = Valore And &H0F ' mask the 4 low bits End Sub ' ' ' *********************** Visualizes a byte in HEX ********************* ' The first display visualizes the number of the channel being ' converted, the second display is off. ' This procedure allows to show a byte in hexadecimal format ' in the two displays on the right. E.g.: 255= FFH, 32= 20H etc. ' Parameters: ' Input : N1 as byte, number to visualize in HEX ' Output : nothing ' ********************************************************************** ' Sub Vis_num(n1 As Byte) ' visualizes a byte in HEX Local Valore As Byte I2cstart ' START sequence I2cwbyte Wsaa1064 ' slave address I2cwbyte Dig3 ' point to display 3 (DY3) Call Cifre(n1 ) ' convert numero1 in 2 figures Valore = Digit(cifh) ' convert tenth in 7 segments I2cwbyte Valore ' write to display DY3 Valore = Digit(cifl) ' convert units in 7 segments I2cwbyte Valore ' write to display DY4 I2cstop ' Stop sequence End Sub ' ' ** Conversion table for 7 segments figure in the range from 0 to 15 ** Tab_7seg: ' num. 0 1 2 3 4 5 6 7 8 9 Data &H3F , &H06 , &H5B , &H4F , &H66 , &H6D , &H7D , &H07 , &H7F , &H6F ' num. A b C d E F Data &H77 , &H7C , &H39 , &H5E , &H79 , &H71 ' ********************************************************************** '