Open source PBP bootloader

[ScaleRobotics]

Might be too early to say this, but it looks like it already does pull it from the ini file, and "tell" the pic. (I just don't see where it tells it yet) One of the parts that confuses me is that all I see is 32 as the maxdatasize for pic16, and 128 for what I think are all PIC18's. So where does 255 come in?

I have a lot more work to do.

[cncmachineguy]

Don't quote me on this just yet, but I think the 18's use a word for the data, so then it would make sense. Also for the ASM program they can get away with just letting it be whatever size because the compiler doesn't care if its too big. No such luck with PBP.

[ScaleRobotics]

Don't quote me on this just yet, but I think the 18's use a word for the data, so then it would make sense.

Oops, just quoted you .....

If that is true, then we should be good with the standard 32 bytes (if it is in bytes for 16F's) of data, then adding the 5 bytes for:

DATA_BUFF   VAR BYTE[37]        ' Start of receive buffer SAME ADDRESS AS COMMAND
COMMAND     VAR DATA_BUFF[0]    ' Data mapped in receive buffer SAME ADDRESS AS DATA_BYTE 
DATA_COUNT1 VAR DATA_BUFF[1]     
ADDRESS_L   VAR DATA_BUFF[2] 
ADDRESS_H   VAR DATA_BUFF[3] 
ADDRESS_U   VAR DATA_BUFF[4]
PACKET_DATA VAR DATA_BUFF[5-36]    'THIS SHOULD BE AN ARRAY I THINK**************

would be 37 bytes for 12F and 16F devices, leaving more room for variables in case we want more PBP bells and whistles later. Then for the 18F's, they all use the 128 words (maybe).

[cncmachineguy]

Newest update, includes Walter's last post regarding Array size. I have to stop here to think about what I am doing. I DON'T like the Read Program Memory at the end. I think it will work as is, but it really looks like ASM to me. I think I need to utilize the READCODE command, just not sure yet how to deal with the address and data. I assume maybe the address needs to be a word, comprised of EEADRH,EEADR. Then I guess the data is also a word. then I guess I just add 2 to the ARRAYPOINTER?

IF anyone wants to chime in on this, now is a good time

As a side note, IF anyone wants to help with this conversion, clearly I am working from the top down. If someone were to work from the bottom up, It would be easy for me to add it to what I have. Then when we meet in the middle, we will be done. No Biggie either way.

ANY testers out there? Still looking for some. I will be able to test compile, but don't feel comfy trying to test the code as I have never used a bootloader so I won't know if problems are with my setup or the code.

' *****************************************************************************
'        Software License Agreement                    
'                                     
' The software supplied herewith by PBP forum members         
' (the “Company”) for Microchip's PICmicro® Microcontroller's is 
' intended and supplied to you, the Company’s customer, for use     
' solely and exclusively on Microchip PICmicro Microcontroller        
' products. The software is owned by the Company and/or its         
' supplier, and is protected under applicable copyright laws. All   
' rights are reserved. Any use in violation of the foregoing          
' restrictions may subject the user to criminal sanctions under        
' applicable laws, as well as to civil liability for the breach of  
' the terms and conditions of this license.                
'                                    
' THIS SOFTWARE IS PROVIDED IN AN “AS IS” CONDITION. NO WARRANTIES, 
' WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED 
' TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A         
' PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT, 
' IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR         
' CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.            
'                                    
'                                     
' This software has been ported from Microchip's AN851 bootloader
' Changes have been made and will be made as the company sees fit.
' This version is for 16F's, there is another version for 18F's
'
'
' Memory Map
'    -----------------
'    |    0x0000    |    Reset vector
'    |            |
'   |    0x0004    |    Interrupt vector
'    |            |    
'    |            |
'    |Boot Block |    (this program)
'     |            |
'    |    0x0200    |    Re-mapped Reset Vector
'    |    0x0204    |    Re-mapped High Priority Interrupt Vector
'    |            |
'    |           |    
'    |            |
'   |Code Space |    User program space
'    |            |
'    |            |
'    |            |
'    |    0x3FFF |
'    -----------------
'
' Incomming data format:
'
'   {STX}{STX}{DATA}{CHKSUM}{ETX}
'              /    \
'     ________/      \____________________________
'    /                                             \
'    {COMMAND}{DLEN}{ADDRL}{ADDRH}{ADDRU}{DATA}...
'
' Definitions:
'
'     STX      -    Start of packet indicator
'    ETX     -    End of packet indicator
'     LEN     -    Length of incomming packet
'     DATA    -    General data up to 255 bytes
'     CHKSUM     -     The 8-bit two's compliment sum of LEN & DATA
'     COMMAND -     Base command
'     DLEN    -    Length of data associated to the command
'     ADDR    -    Address up to 24 bits
'     DATA     -    Data (if any)
'
'
' Commands:
'
'     RD_VER        00    Read Version Information
'     RD_MEM        01    Read Program Memory
'     WR_MEM        02    Write Program Memory
'     ER_MEM        03    Erase Program Memory (NOT supported by PIC16)
'     RD_EE        04    Read EEDATA Memory 
'     WR_EE        05    Write EEDATA Memory 
'     RD_CONFIG    06    Read Config Memory (NOT supported by PIC16)
'     WT_CONFIG    07    Write Config Memory (NOT supported by PIC16)
'
' ****************************************************************************

' *****************************************************************************
CHKSUM        VAR    BYTE        ' Checksum accumulator
COUNTER        VAR    BYTE        ' General counter
ABTIME        VAR    BYTE
RXDATA        VAR    BYTE
TXDATA        VAR    BYTE
TEMP        VAR    BYTE
ARRAYPOINTER VAR BYTE
FAKEW        VAR BYTE

TEMPFLAG    VAR BIT

PCLATH_TEMP    VAR    BYTE        ' Interrupt context
STATUS_TEMP    VAR    BYTE        ' save/restore registers
W_TEMP        VAR    BYTE

' Frame Format
'
'  {STX}{STX}[{COMMAND}{DATALEN}{ADDRL}{ADDRH}{ADDRU}{...DATA...}]{CHKSUM}{ETX}

DATA_BUFF    VAR    BYTE[37]        ' Start of receive buffer SAME ADDRESS AS COMMAND
    
COMMAND        VAR    DATA_BUFF[0]        ' Data mapped in receive buffer SAME ADDRESS AS DATA_BYTE
DATA_COUNT    VAR    DATA_BUFF[1]
ADDRESS_L    VAR    DATA_BUFF[2]
ADDRESS_H    VAR    DATA_BUFF[3]
ADDRESS_U    VAR    DATA_BUFF[4]
PACKET_DATA    VAR    DATA_BUFF[5]    'Is this Valid? It is now!
' *****************************************************************************


'  This is the remapping section, note the interrupt also saves context
' *****************************************************************************
@    ORG    0x0000            ' Re-map Reset vector **Not sure how to set the address to start at
VReset:
    PCLATH = 0
    goto    Setup                                

@    ORG    0x0004            'standard interrupt vector **again not sure of the PBP equal for ORG
VInt:
    W_TEMP = W               'I am assuming this will be the "W" register            
    STATUS_TEMP = STATUS   'We may have trouble here. ASM uses SWAP so as not to affect the status
    STATUS = 0
    PCLATH_TEMP = PCLATH
    PCLATH = 0
    goto    RVInt        ' Re-map Interrupt vector        

' *****************************************************************************
 *****************************************************************************
' Setup the appropriate registers.
Setup:
    clrwdt
    READ $ff,temp                 'get the value of last EEPROM location
    IF temp = $ff then goto SRX  'BL startup
    goto    RVReset                 ' If not 0xFF then normal reset    

SRX:
    RCSTA = %10000000        ' Setup rx and tx, CREN disabled
    TRISC.6 = 0             ' Setup tx pin        
    TXSTA = %00100110            
    STATUS.IRP = 1
' *****************************************************************************


' *****************************************************************************
Autobaud:
'
' ___     __________            ________
'    \__/           \__________/
'       |                     |
'       |-------- p ----------|
'
'    p = The number of instructions between the first and last
'           rising edge of the RS232 control sequence 0x0F. Other 
'        possible control sequences are 0x01, 0x03, 0x07, 0x1F, 
'         0x3F, 0x7F.
'
'    SPBRG = (p / 32) - 1      BRGH = 1
                                        

    OPTION_REG = %00000011    'sets tmr0 to 1:16 prescale
    STATUS.RP0    = 0                        
    RCSTA.CREN = 0                            

    gosub    WaitForRise                            
     
    TMR0 = 0             ' Start counting            

    gosub    WaitForRise                            

    ABTIME = TMR0         ' Read the timer        
    TEMPFLAG = ABTIME.0
    ABTIME = ABTIME }}1                            
    IF !TEMPFLAG THEN ABTIME.0 = 0 'Rounding    
    SPBRG = ABTIME
    RCSTA.CREN = 1         ' Enable receive    

    TEMP = RCREG        ' To clear the Rx buffer                    
    TEMP = RCREG        ' Both of them                        
                        
    OPTION_REG = %11111111 'Return Option Reg to reset state                            
                            
' *****************************************************************************


' *****************************************************************************
' Read and parse the data.
StartOfLine:                        
    GOSUB    RdRS232            ' Look for a start of line    
    IF RXDATA != STX THEN Autobaud        '{STX}{STX}                
                         
    ARRAYPOINTER = 0        ' Point to the beginning of Array                        

    CHKSUM    = 0             ' Reset checksum        
        
GetNextDat:            
    GOSUB    RdRS232            ' Get the data            
    IF RXDATA = STX    THEN StartOfLine    ' Check for a STX            
                            ' Yes, start over            

NoSTX:
    IF RXDATA = ETX THEN CheckSum    ' Check for a ETX            
                                ' Yes, examine checksum        

NoETX:
    IF RXDATA = DLE THEN GOSUB RdRS232 ' Check for a DLE
                                       ' Yes, Get the next byte    
    
NoDLE:
    DATA_BUFF[ARRAYPOINTER] = RXDATA   ' Store the data        
    CHKSUM = CHKSUM + RXDATA           ' Get sum                
    ARRAYPOINTER = ARRAYPOINTER + 1                                

    goto    GetNextDat                        

CheckSum:
    IF CHKSUM = 0 THEN Autobaud  ' Checksum test                    
' ***********************************************


' ***********************************************
' Pre-setup, common to all commands.                                    
    EEADR = ADDRESS_L        'Set all possible pointers                                
    EEADRH = ADDRESS_H                                                        

    ARRAYPOINTER = 5        'start of data in array                            

    COUNTER = DATA_COUNT     'Setup counter                                        
    IF COUNTER = 0 THEN VReset    'Non valid count (Special Command)    
' ***********************************************

' ***********************************************
' Test the command field and sub-command.                    
CheckCommand
    IF COMMAND } 7 THEN Autobaud ' Test for a valid command                                    
    SELECT CASE COMMAND          ' Perform calculated jump        
        CASE 0
            goto    ReadVersion        ' 0                    
        CASE 1
            goto    ReadProgMem        ' 1                    
        CASE 2
            goto    WriteProgMem    ' 2                    
        CASE 3
            goto    StartOfLine        ' 3                    
        CASE 4
            goto    ReadEE            ' 4                    
        CASE 5
            goto    WriteEE            ' 5                    
        CASE 6
            goto    StartOfLine        ' 6                    
        CASE 7
            goto    StartOfLine        ' 7                    
    'maybe add jump to reset vector in this table
'***********************************************



' ***********************************************
' Commands
' ************* Read Version
' In:    {STX}{STX}[{0x00}{0x02}]{0xFF}{ETX}
' OUT:    {STX}{STX}[{0x00}{VERL}{VERH}]{CHKSUM}{ETX}
ReadVersion:                                
    DATA_BUFF[2] = MINOR_VERSION                                                        
    DATA_BUFF[3] = MAJOR_VERSION                                                        

    FAKEW = 4                                
    goto    WritePacket                            

'*************Read Program Memory
    
' In:    {STX}{STX}[{0x01}{DLEN}{ADDRL}{ADDRH}{ADDRU}]{CHKSUM}{ETX}
' OUT:    {STX}{STX}[{0x01}{DLEN}{ADDRL}{ADDRH}{ADDRU}{DATA}...]{CHKSUM}{ETX} 
ReadProgMem:                                
RPM1:                                
    EECON1.EEPGD = 1                        
    EECON1.RD = 1                        
    @nop                'not sure how to convert this to PBP                    
    @nop                                                                
    DATA_BUFF[ARRAYPOINTER] = EEDATA                            
    ARRAYPOINTER = ARRAYPOINTER + 1                                
    DATA_BUFF[ARRAYPOINTER] = EEDATH                            
    ARRAYPOINTER = ARRAYPOINTER + 1                                
    EEADR = EEADR + 1
    IF EEADR = 0 then                            
       EEADRH = EEADRH + 1                            
    ENDIF
    COUNTER = COUNTER - 1                            
    IF COUNTER > 0 THEN RPM1            ' Not finished then repeat    

    DATA_COUNT = (DATA_COUNT << 1) + 5    ' Setup packet length        
                    
    goto    WritePacket                        

'************* Write Program Memory