CWrite Issues on 16F – 31 days old

[mjturner]

I want to commit some values to EEPROM, but it seems they no longer include the separate EEPROM area anymore. So I'm having to use the code flash memory. I'm struggling to get CRead/CWrite/CErase to function as expected.

The following is the core part of the code where the issue is. I've included fuses just in-case they have a bearing.

The basic idea is that it reads a known location, if it isn't zero then we know the chip has been flashed and is new. Therefore it generates valid starting values and saves them to flash memory. The issue is that it always sees a non-zero value. Which would indicate to me that it isn't writing the values. However I've no idea why the write would be failing.

The value used for StoredAddr is just a value that I picked that would be above the program size, I picked one divisible by 512 so it should be on a 32 byte boundary in theory. I did originally try just writing the bytes I needed, but tried putting the full 32 in there just in case that was the issue.

Any thoughts on what I might be doing wrong?

Device = 16F15345


Config1 FEXTOSC_OFF, RSTOSC_HFINT32, CLKOUTEN_OFF, CSWEN_ON, FCMEN_ON
Config2 MCLRE_OFF, PWRTE_OFF, LPBOREN_OFF, BOREN_ON, BORV_LO, ZCD_OFF, PPS1WAY_ON, STVREN_ON
Config3 WDTCPS_WDTCPS_31, WDTE_OFF, WDTCWS_WDTCWS_7, WDTCCS_HFINTOSC
Config4 BBSIZE_BB512, BBEN_OFF, SAFEN_OFF, WRTAPP_OFF, WRTB_OFF, WRTC_OFF, WRTSAF_OFF, LVP_ON
Config5 CP_OFF


;**** End of Fuse Configurator Settings ****
;-------------------------------------------------------------------------------


  Xtal = 32
  All_Digital = TRUE    ' Set PORTA and PORTC to all digital
  
  Declare Optimiser_Level = 0



Symbol StoredAddr =7680


ReadSequence:
  vstemp=CRead StoredAddr + 4
  If vstemp<>0 Then
    ' This is a re-programmed device, so reset the server and sequence codes
    SerOut SerialOutDiag,84,["Keys reset"]
    SerOut SerialOutDiag,84,[13]
    SerOut SerialOutDiag,84,[10]
    vstemp=0
    Clear ServerSequence
    OrbSequence=1
    GoSub UpdateSequence
    GoSub WiFi_PowerOn
    GoSub DoWipeKeys
    DelayMS 1000
    GoSub DoPowerDownWiFi
  Else
    ServerSequence.LowByte=CRead StoredAddr
    ServerSequence.HighByte=CRead StoredAddr+1
    OrbSequence.LowByte=CRead StoredAddr+2
    OrbSequence.HighByte=CRead StoredAddr+3
    OrbSequence=OrbSequence+20
  End If
  Return


UpdateSequence:
  CErase StoredAddr
  CWrite StoredAddr,[ServerSequence.LowByte,ServerSequence.HighByte,OrbSequence.LowByte,OrbSequence.HighByte,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255]
  Return

[Tim]

Some thoughts

Ensure StoreAddr is on the correct boundary and you are writing the correct number of bytes. Some are as low as 32 bytes others 64. Look at the data sheet or the PPI file for the device.

Tim

[mjturner]

Some thoughts

Ensure StoreAddr is on the correct boundary and you are writing the correct number of bytes. Some are as low as 32 bytes others 64. Look at the data sheet or the PPI file for the device.

Tim

Thanks Tim. How do I figure out the boundary? This PIC lists it as 32 byte pages. Therefore I figured if the address is divisible by 32 it should be OK, or is that assumption incorrect?

Also the datasheet doesn't mention about having to write the full 32 bytes, only that you can only write to previously erased bytes. Nothing in the EWrite command seemed to indicate that I had to write all 32 bytes. However I did give that a go and it didn't seem to help.

[Tim]

Sorry for the delay

Yes if it says 32 byte then its a number divisible by 32. eg $4EC0 which is 32 x 630

You have to write from the same 32 byte boundry

Ewrite basically writes to a set of regs (in the pic) then it makes the pic write that lot to flash memory. Proton will not do the write until it counts the full x number of data is written

In the PPI file it has the number expected

BLOCK=32 ; Size of the Code Memory Write Segment (in Words)
ERASE=32 ; Size of the Code Memory Erase Segment (in Words)

So for example you want to write to memory a series of data

1 Erase the block
2 Write all the data, this can be as long command as you have done or a loop

Once Proton sees enough data written it will complete the command

I think I have this right the pic uses 14bits data so you need to write words
And you need to check the fuses are set right as you can prevent data writing to certain memory blocks

[mjturner]

Tim - thanks. Yes that is the bit I didn't understand - while the PIC datasheet says you can write just the bytes you want, Proton only commits the write when it has a full block. I ran a few tests to dump out the ram, and indeed it only changed when 32 bytes were in the CWrite command. All works now! Thank you.