' **********************************************************************
' ** Program : gmbsere.bas   -   Version :  1.2  -  18 November 2004  **
' ** Compiler : BASCOM 8051 DEMO, (IDE and LIB V.2.0.11.0)            **
' ** Board : GMB HR84 with GMM 935                                    **
' ** Corporate:   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                      **
' ** Written by:  Graziano Gaiba                                      **
' **********************************************************************
'
' This demo is a simple example of communication capableto work with all
' electric protocols available on CN2 (RS 232, RS 422, RS 485, current loop or
' TTL).
' In detail, through high level functions, it is possible to program baud rate
' from console, then each character received from serial port is sent to the
' port itself; reception of character 'r' decides how to manage the
' communication direction (signal DIR) for RS 422 and RS 485.
'
' 24.06.03 - Rel 1.1 By Graziano Gaiba
'
' 18.11.04 - Rel 1.2 By Graziano Gaiba
'   Modified to run on a GMM 935
'
'****************** Compiler directives **************************
'N.B. In Options | Compiler | Misc perform these settings:
'               Register File = 89LPC935.DAT
'               Byte End(Hex) = A0
'               Size warining  = 7167
$regfile = "89lpc935.dat"
$romstart = &H0                           ' start address of code for FLASH
$ramstart = &H0                           ' start address of external RAM
$ramsize = &H200                          ' 256 bytes of external RAM
$crystal = 11059200                       ' Maximun Microcontroller clock
$baud = 19200                             ' RS-232 baud rate
$large                                    ' 16 bit addressing for jumps
                                          ' (Not for demo version)
$map                                      ' Generates address map
'
'****************** Constants declatation ***********************
'
Const Cret = 13                           ' Carriage return
Const Nl = 10                             ' New line
Const Clrscr = 12                         ' Clear screen
Const Bell = 7                            ' Bell
Const Rcint = 7372800                     ' Internal RC clock frequency
Const Qz11m = 11059200                    ' External clock frequency
Const Enable_422_485 = 1                  ' Enables driver RS 422 or 485
Const Disable_422_485 = 0                 ' Disable driver RS 422 or 485
'
'****************** Variables declaration **********************
'
' General purpose
Dim S1 As String * 1                      ' General purpose Byte
Dim S0 As Bit                             ' General purpose Bit
Dim I As Byte
Dim Hlpb As Byte , M As Byte              ' General purpose Byte
Dim M1 As Byte , M2 As Byte               ' General purpose Byte
Dim T As Byte , S As Byte , V As Byte     ' General purpose Byte
Dim Hlpw As Word , Ind As Word            ' General purpose Word
Dim Hlpl As Long                          ' General purpose Long
Dim Scelta As String * 1                  ' One character string
' Variables to manage serial communication, clock and delays
Dim Chav As Bit
Dim St As Byte , Chser As Byte
Dim Br As Long                            ' Serial Baud Rate
Dim Cclk As Long                          ' CPU clock frequency
Dim D As Word , Del1ms As Word , Del As Word       ' Delays management
'
'********************* Procedures declaration *************************
'
Declare Sub Get_clk                       ' Acquires clock frequency
Declare Sub Init                          ' General initialization
Declare Sub Ritardo(del As Word)          ' Calibrated delay
Declare Sub Iniser(br As Long , St As Byte)       ' Serial initialization
Declare Sub Check                         ' Verifies peripherals

Declare Sub Demoser()
Declare Sub Txser(chser As Byte)          ' Sends a character
Declare Sub Rxser                         ' Checks and receives a character
                                          ' non-blocking
'
'************************** Main program ******************************
'
Main:
Call Init                                 ' Initializes the module
Call Get_clk                              ' Acquires CPU clock frequency
Call Iniser(19200 , 1)                    ' Initializes serial for console
' Performs a delay of about 2 seconds to allows the presence of emulation
' terminal program for console (i.e. HYPERTERMINAL) and contemporaneosly blinks
' the activity LED DL1 of the card.
' Uses general purpose variable i
P0m1 = P0m1 Or &H40                       ' Sets P0.6 in mode 3=OpenDrain
P0m2 = P0m2 Or &H40
For I = 1 To 16                           ' 16 cycles of 125 msec=2 sec
  P0.6 = Not P0.6                         ' Complements activity LED
  Call Ritardo(125)                       ' Delays about 125 msec
Next I


Do
   Print Chr(clrscr);                     ' Pulisce lo schermo
   Print "Demo 1.2 for GMM935 ds300803 + GMBHR84 ds220503"
   Call Check                             ' Controllo interno
   Call Demoser()
Loop

End
'
'************************ Program end ***************************
'
'
'**************************** Procedures ********************************
'
Sub Demoser
  Print
  Print "RS 232,RS 422,RS 485,current loop or TTL serial line on CN2"
  Print
  Print "This demo receives and transmits at low level, if F is received it resets to"
  Print " 19200 Baud, 1 stop."
  Print "If r is received it complements the status of signal dir."
  Print "Jumper J7 must be in 1-2."
  Input "Baud Rate= " , Br
  Input "Stop Bit= " , St
  ' Sets P2.0 as output (push pull)
  P2m1.0 = 0
  P2m2.0 = 1
  S0 = Disable_422_485
  P2.0 = 1
  Call Ritardo(10)                        ' Wait end of tx of last char
  Call Iniser(br , St)                    ' Initialize serial with user input
  Chser = 0                               ' To avoid exiting immediatly
  Do
    Call Rxser                            ' Check for char received
    If Chav = 1 Then                      ' IF char available
      Call Txser(chser)                   ' Send it
      If Chser = "r" Then
         If S0 = Disable_422_485 Then
            S0 = Enable_422_485
            P2.0 = 0
         Else
            S0 = Disable_422_485
            P2.0 = 1
         End If
      End If
    End If
  Loop Until Chser = "F"                  ' Wait to receive F
  Call Ritardo(10)                        ' Wait end of tx of last char
  Call Iniser(19200 , 1)                  ' Initialize serial for console
End Sub
'
' Sends through hardware serial line of the card the character in
' parameter char.
Sub Txser(chser As Byte)
   Bitwait Scon.1 , Set                   ' Wait for transmitter free
   Scon.1 = 0                             ' Reset bit of transmission completed
   Sbuf = Chser                           ' Send character
End Sub
'
'
' Check for reception on hardware line of the card and return the
' eventually received character in variable chser;
' also set the boolean flag chav to indicate whether the character is available
' or not.
Sub Rxser
   If Scon.0 = 1 Then                     ' Check if char received
      Scon.0 = 0                          ' Reset bit char received
      Chser = Sbuf                        ' Get char received
      Chav = 1
    Else
      Chav = 0                            ' No char received
   End If
End Sub
'
'
'********************** General purpose subroutines ****************************
' Reads the configuration byte UCFG1 on FLASH thanks to IAP procedures of
' P89LPC932 Boot Rom. Returns the global variable cclk set with the CPU clock
' frequency, with no control of the possible errors.
Sub Get_clk
   mov     A,#&H03                                  ' Uses command Misc. Read
   mov     R7,#&H00                                 ' Reads register UCFG1
   lcall   &HFF03                                   ' Calls IAP proc. at PGM_MTP addr.
   mov     A,R7                                     ' Saves result
   anl     A,#&H07                                  ' Masks bits with CPU clock
   Select Case Acc
      Case &H00 : Cclk = Qz11m            ' Ext. crystal clock frequency
      Case &H03 : Cclk = Rcint            ' Internal RC clock frequency
   End Select
End Sub
'
'
' Inizializza risorse, variabili e periferiche in modo da poter eseguire
' correttamente tutto il programma demo.
Sub Init
   Disable Interrupts                     ' Disabilita gli interrupts

   P1m1 = 0                               ' Necessario per la seriale RS232
   ' IN1 <- P0.0
   ' IN2 <- P0.1
   ' IN3 <- P0.2
   ' IN4 <- P1.4
   ' IN5 <- P0.3
   ' IN6 <- P0.4
   ' IN7 <- P0.5
   ' IN8 <- P0.7
   '
   ' OUT A1 -> P1.6
   ' OUT A2 -> P1.7
   ' OUT B1 -> P2.1
   ' OUT B2 -> P2.7

   Pt0ad = 0                              ' Set P0.1-5 come as digital I/O.
   M1 = P0m1                              ' Set P0.0-5 and P0.7 as input only.
   M2 = P0m2
   M1 = M1 Or &HDF
   M2 = M2 And &H40
   P0m1 = M1
   P0m2 = M2
   '
   M1 = P1m1                              ' Set P1.4 as input only and
   M2 = P1m2                              ' P1.6 and P1.7 as open drain output
   M1 = M1 Or &HD0
   M2 = M2 Or &HC0
   M2 = M2 And &HEF
   P1m1 = M1
   P1m2 = M2
   '
   M1 = P2m1                              ' Set P2.1 and P2.7 as
   M2 = P2m2                              ' open drain output
   M1 = M1 Or &H82
   M2 = M2 Or &H82
   P2m1 = M1
   P2m2 = M2
End Sub
'
'
' Checks right functionality of internal devices with possible remakes.
' Uses general purpose variable st,t,m,ind,hlpw
Sub Check
   Deecon = &H01
   T = Peek(&Hff)
   Deeadr = &HFF
   T = 1
   Ind = &HF7
   Do
     M = Peek(&H07)
     If M.7 = 1 Then
       M = M And &H03
       Ind = M + &HF8
       T = Peek(ind)
      Else
       T = 0
     End If
     St = Deecon
     St = St And &H80
   Loop Until St <> 0
   T = St
   St = Deedat
   Do
     M = Peek(ind)
     Incr Ind
     If Ind = &HFF Then Ind = &HF9
     Hlpw = 0
     Do
       Incr Hlpw
       M = Peek(ind)
     Loop Until St.0 = 0 Or Hlpw >= 1000
     T = T + M
     Hlpw = Ind + T
      M = Peek(t)
     If St = 0 Then
       Incr T
     Else
       Call Ritardo(1)                    ' 1 msec pause
     End If
   Loop Until St = 0
End Sub
'
'
' Performs a calibrated delay long as many milliseconds as specified in the
' passed parameter del, according with the clock frequency saved in cclk
' variable, with no use of BASCOM instructions that use a fixed and preset
' value of clock.
Sub Ritardo(del As Word)
  If Cclk = Rcint Then
    Del1ms = 73                           ' Value for 1 msec at 7 MHz
   Else
    Del1ms = 110                          ' Value for 1 msec at 11 MHz
  End If
  Do
    For D = 0 To Del1ms                   ' Cycle for 1 msec delay
    Next D
    Del = Del - 1
  Loop Until Del = 0
End Sub
'
'
'*********************** Serial management subroutines *************************
' Initializes the serial line with:
'    Bit x chr = 8
'    Stop bit = 1 or 2 according with ST parameter
'    Parity = None
'    Baud rate = value of BR parameter
' by using the proper baud rate generator of microcontroller and his clock
' frequency saved on global variable cclk.
' Uses general purpose variables hlpw,hlpl
Sub Iniser(br As Long , St As Byte)
  Pcon = Pcon And &HBF                    ' Resets bit SMOD0 to set mode
  If St = 1 Then
    Scon = &H52                           ' Mode 1 (1 stop),No multiproc,Rx enable
   Else
    Scon = &HDA                           ' Mode 3 (2 stop),No multiproc,Rx enable
  End If
  Brgcon = &H02                           ' Sets passed baud rate
  Hlpl = Br * 16                          ' Calculates divisor for baud
  Hlpl = Cclk - Hlpl
  Hlpl = Hlpl / Br
  Hlpw = Loww(hlpl)
  Brgr0 = Low(hlpw)
  Brgr1 = High(hlpw)
  Brgcon = &H03
End Sub