Open source PBP bootloader

[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