Hserin parsing string...again?

[kevlar129bp]

Hello all,

This has probably been answered in a million different threads...all of which I have read, which leads me to my question.
What I'de like to do is receive a string into the usart similar to this:

ABC123

What I would like to do is store the ABC in a word var to send through a
select case statement and...
store the 123 in a byte var to use later in code.

The commands coming into the usart will always be this format, for ex:

ABC123
XYZ255
PQR002

LETTER-LETTER-LETTER-NUMBER-NUMBER-NUMBER

NUMBER-NUMBER-NUMBER not to exceed 256.

Any help parsing these from the RCREG or a 6 byte ring buffer?

Thanks to all,
Chris

[kevlar129bp]

Am I on the right track?

Ser_Cmd_Word var word
Ser_Cmd_Val var byte

Start:
    ...	
    If PIR1.5 = 1 Then Goto New_SerIn    
   ...
GOTO Start

New_SerIn:
    PIE1 = %00000000                                  'Disable interrupts
        hserin [dec3 Ser_Cmd_Word, dec3 Ser_Cmd_Val]
        LCDout $fe, 1, "COMMAND RECEIVED"
        Lcdout $fe, $c0, "-----", Ser_Cmd_Word, Ser_Cmd_Val, "-----" 
        pause 3000                 'Pause for 3 seconds for user viewing
    PIE1 = %01110000                                  'Enable interrupts
Return

Thanks much

[Darrel Taylor]

3 letters won't fit in a word variable very easily.
Although it can be done, with limitations.

The second part ...
dec3 Ser_Cmd_Val
should work fine.

Is there a limit to the 3 letter sequences, or could it be anything?

Do you have PBP 2.60?

[kevlar129bp]

If I understand your question correctly...yes, 3 characters- no more - no less. I did discover the 16 bit word size after my post...newbie move, i admit . How about me changing the command to:

LETTER LETTER NUMBER NUMBER NUMBER

Easier coding that way? The ultimate goal is to run the LETTER LETTER through
a select case statement like:

Chk_Cmd:
    select case Ser_Cmd_word
        case TT    'Torch Target
            TTV_val = Ser_Cmd_Val
        Case XX    'Another Command
            'SomeByteVar = Ser_Cmd_Val
        Case else
            LCDout $fe, 1, " COMMAND NOT IN "
            Lcdout $fe, $c0, " DEFINED SCOPE! "
    END SELECT
RETURN

Am I on the right track?
Thanks again.

[Darrel Taylor]

Well, I was referring to how many 3-letter combinations, and if you have PBP 2.60 it could be done differently.
However, let's go with what you have ...

First, I'd recommend starting the command sequence with a known character, like "$". This can keep the data "synced" by making it easy to find the beginning of each "packet". Then use the WAIT("$") modifier in HSERIN.

If you only have a few different commands, they can be reduced to 1 letter, which makes it work well with the Select Case statement. Then the packets might look like ...

$T123
$P255

Also, don't enable interrupts.
HSERIN does not use interrupts. And enabling them without handler routines being defined will cause the program to lock up.

If you want to keep the 2-letter commands, that can be done too, but it's a little trickier.

[kevlar129bp]

Will this fly...nearest you can tell?

'PIC 16F917

'------------------------------------------------------------------------------------------

'Clock setup
    Define OSC 20
'Interrupt setups
    INTCON = %11000000      'Enable: Global interrupts, Peripheral interrupts
    PIE1 = %01110000        'Enable: ADC interrupt, Rx interrupt, Tx interrupt
'Pin setups
    ANSEL = %10000000       'Analog input on E.2/AN7, all others digital
    TRISA = %11000000       'PortA: 0-5 = output, 6-7 = input
    TRISB = %11111111       'PortB: 0-7 = input (defaults)
    TRISC = %11011111       'PortC: 0-5&7 = input, 6 = output
    TRISD = %11111111       'PortD: 0-7 = input (defaults)
    TRISE = %00000100       'PortE: 0&1 = output, 2 = input, 3-7 = N/A
'Vref setups
    VRCON = %10001111       'Enable Vref, set high range, set value (3.59 Vdc)
'Usart setups
    SPBRG = %00011001       'Set 9600 baud w/20MHz clock
    TXSTA = %00100110       'Enable transmit, set BRGH high
    RCSTA = %10010000       'Enable Usart, enable receiver
'ADC setups
    ADCON0 = %10011101      'Right justify (8 bit result in ADRESL), Select ch.7, enable ADC
    ADCON1 = %00100000      'Set ADC clock to 625kHz

'------------------------------------------------------------------------------------------    
        
'LCD setup (16 x 2 lines)
    Define LCD_BITS 4       '4 data interface lines
    Define LCD_DREG PORTA   'LCD data port
    Define LCD_DBIT 0       'LCD data bits 0-4
    Define LCD_RSREG PORTA  'LCD register select port
    Define LCD_RSBIT 4      'LCD register select bit
    Define LCD_EREG PORTA   'LCD enable port
    Define LCD_EBIT 5       'LCD enable bit

'------------------------------------------------------------------------------------------
Ser_Cmd_Numb var byte
Ser_Cmd_Val var byte
THC_Enable_In var PORTC.0
TTV_Val var byte
HYS_Val var byte
Torch_V_Now var byte
Torch_Up var PORTE.0
Torch_Dn var PORTE.1
TTV_Val = 120
HYS_Val = 0

pause 1000                  'Pause for 1 second for LCD warmup
LCDout $fe, 1, "---LCD WARMUP---"
Lcdout $fe, $40, "----FINISHED----"
pause 5000                 'Pause for 5 seconds for user viewing

Start:
    IF THC_Enable_In = 0 then
        PIE1.6 = 0        'Turn off ADC interrupt
        PIE1.5 = 1        'Turn on Rx interrupt
        LCDout $fe, 1, "READY TO RECEIVE"
        Lcdout $fe, $40, "COMMAND:C###V###"
        If PIR1.5 = 1 Then Goto New_SerIn
        PAUSE 500
        GOTO START
    ELSE
        PIE1.6 = 1        'Turn on ADC interrupt
        PIE1.5 = 0        'Turn off Rx interrupt
        ADCON0.1 = 1    'Start ADC conversion        
        if PIR1.6 = 1 THEN GOTO New_ADC
        LCDout $fe, 1, "TARGET VDC : ", dec TTV_Val
        Lcdout $fe, $40, "PLASMA VDC : ", dec Torch_V_Now
        select case Torch_V_Now
            case Torch_V_Now > TTV_Val + hys_val
                high torch_dn
                low torch_up
            case Torch_V_Now < TTV_Val - hys_val
                high torch_up
                low torch_dn
            case else
                low torch_up
                low torch_dn
        end select
    endif
GOTO Start

New_ADC:
    Torch_V_Now = ADRESL    
    PIR1.6 = 0
Return

New_SerIn:
'******Command structure is: C###V###    
    PIE1 = %00000000                                                    'Disable interrupts
        hserin 100, start, [wait ("C"),dec3 Ser_Cmd_numb]
        hserin 100, start, [wait ("V"),dec3 Ser_Cmd_val]
        LCDout $fe, 1, "COMMAND RECEIVED"
        Lcdout $fe, $40, "-- C", dec Ser_Cmd_numb,"  V", dec Ser_Cmd_val, " --" 
        pause 3000                                                  'Pause for 3 seconds for user viewing
        GOTO Chk_Cmd                                                      
    PIE1 = %01110000                                                    'Enable interrupts
Return

Chk_Cmd:
    select case Ser_Cmd_numb        '001 to 256
        case 1                      'Torch Target Voltage
            TTV_val = Ser_Cmd_Val
        case 2                     'Hysteresis Value
            HYS_Val = Ser_Cmd_Val
        Case else
            LCDout $fe, 1, " COMMAND NOT IN "
            Lcdout $fe, $40, " DEFINED SCOPE! "
    END SELECT
RETURN

Cut and shuffle as you will . Thanks guys.

Chris