added length field for messages

git-svn-id: https://svn.spreadspace.org/pic/trunk@46 a09c6847-51d9-44de-8ef2-e725cf50f3c7

1 files changed, 48 insertions, 81 deletions

diff --git a/bootloader/bootloader.asm b/bootloader/bootloader.asm
index f8b609c..ff23d61 100644
--- a/bootloader/bootloader.asm
+++ b/bootloader/bootloader.asm
@@ -37,11 +37,10 @@ VERSION_MAJ     EQU       .0
 VERSION_MIN     EQU       .1
 DEVID_H         EQU       H'20'
 DEVID_L         EQU       H'82'
-FSS             EQU       .16
-MESS_H          EQU       .0
-MESS_L          EQU       .64
+FSS             EQU       .16         ; writing is done 8 words at a time but 16 words get erased
+MESS            EQU       .64         ; this limit is because of to combuff size and single byte len field for messages
 SUPPORTED_H     EQU       .0
-SUPPORTED_L     EQU       b'00011110' ; read/write flash, read/write eeprom
+SUPPORTED_L     EQU       b'00000110' ; only read/write flash is supported by now
 
   ;; ERROR codes
 E_OK            EQU       .0
@@ -76,7 +75,7 @@ current_cmdlen  EQU       H'0070'
 csum            EQU       H'0071'
 
 flags           EQU       H'007D'
-#define F_WEEP            flags,0
+#define F_NEW_CMD         flags,0
 
 cnt2            EQU       H'007E'
 cnt1            EQU       H'007F'
@@ -104,6 +103,9 @@ uart_tx_byte
   return
 
 send_answer
+  addlw     .3
+  movwf     combuff + .1
+  decf      combuff + .1,w
   movwf     cnt1
   movlw     combuff
   movwf     FSR
@@ -119,19 +121,6 @@ send_answer_next
   call      uart_tx_byte
   return
 
-get_cmdlen
-  addwf     PCL,f
-  retlw     .0            ; invalid
-  retlw     .1            ; identify:     <csum>
-  retlw     .1            ; boot:         <csum>
-  retlw     .1            ; reset:        <csum>
-  retlw     .3            ; read flash:   addr | <csum>
-  retlw     .3 + .2*FSS   ; write flash:  addr | data | <csum>
-  retlw     .5            ; read eeprom:  addr | len | <csum>
-  retlw     .5            ; write eeprom: addr | len | data | <csum> (minimal)
-  retlw     .2            ; read config:  nr | <csum>
-  retlw     .4            ; write config: nr | word | <csum>
-
 get_name
   addwf     PCL,f
   nop
@@ -197,6 +186,8 @@ uart_rx_byte              ; process received command
   movf      RCREG,w
   movwf     INDF
   incf      FSR,f
+  btfss     F_NEW_CMD
+  goto      wait_cmd_len
   movf      current_cmdlen,f
   btfsc     STATUS,Z
   goto      new_cmd
@@ -208,39 +199,43 @@ uart_rx_fe                ; recover from framing error
   movf      RCREG,w
   goto      wait_new_cmd
 
+wait_cmd_len
+  bsf       F_NEW_CMD
+  goto      wait_cmd
+
 new_cmd                   ; got new command code
   movf      combuff,w
   sublw     CMD_MAX
   btfss     STATUS,C
   goto      invalid_cmd
-  movf      combuff,w
-  call      get_cmdlen
+  decfsz    combuff + .1,w
+  goto      load_cmdlen
+  goto      invalid_cmd
+load_cmdlen
   movwf     current_cmdlen
+  decfsz    current_cmdlen,f
   goto      wait_cmd
-
-invalid_cmd               ; received command code is not known
+invalid_cmd               ; received command code is not known or len is bogus
   movlw     E_INV_CMD
-  movwf     combuff + .1
-  movlw     .2
+  movwf     combuff + .2
+  movlw     .1
   call      send_answer
   goto      wait_new_cmd
 
 exec_cmd                  ; command is correct and complete
-  ;; TODO: check csum -> csum for write eeprom will not be correct because
-  ;;       it isn't finished yet....???
+  ;; TODO: check csum
   movf      combuff,w     ; dispatch commands
   addwf     PCL,f
   goto      wait_new_cmd
-  goto      cmd_identify
-  goto      cmd_boot
-  goto      cmd_reset
-  goto      cmd_r_flash
-  goto      cmd_w_flash
-  goto      cmd_r_eeprom
-  goto      cmd_w_eeprom
-  goto      cmd_r_config
-  goto      cmd_w_config
-  goto      wait_new_cmd
+  goto      cmd_identify        ; identify
+  goto      cmd_boot            ; boot
+  goto      cmd_not_impl        ; reset
+  goto      cmd_r_flash         ; read flash segment
+  goto      cmd_w_flash         ; write flash segment
+  goto      cmd_not_impl        ; read eeprom
+  goto      cmd_not_impl        ; write eeprom
+  goto      cmd_not_impl        ; read config
+  goto      cmd_not_impl        ; write config
 
   ;; ** Command Handlers ********************
   ;; ** identify *******
@@ -249,6 +244,9 @@ cmd_identify
   movf      combuff,w
   call      uart_tx_byte
 
+  movlw     .22
+  call      uart_tx_byte
+
   movlw     E_OK
   call      uart_tx_byte
 
@@ -273,10 +271,7 @@ cmd_identify_send_name
 
   movlw     FSS
   call      uart_tx_byte
-
-  movlw     MESS_L
-  call      uart_tx_byte
-  movlw     MESS_H
+  movlw     MESS
   call      uart_tx_byte
 
   movlw     SUPPORTED_L
@@ -291,8 +286,8 @@ cmd_identify_send_name
   ;; ** boot *******
 cmd_boot
   movlw     E_OK
-  movwf     combuff + .1
-  movlw     .2
+  movwf     combuff + .2
+  movlw     .1
   call      send_answer
   goto      USERVECT
 
@@ -308,39 +303,11 @@ cmd_w_flash
   call      send_answer
   goto      wait_new_cmd
 
-  ;; ** read eeprom *******
-cmd_r_eeprom
-  ;; call      read_eeprom
-  movlw     E_ADDR_INVALID
-  movwf     combuff + .1
-  movlw     .2
-  call      send_answer
-  goto      wait_new_cmd
-
-  ;; ** write eeprom *******
-cmd_w_eeprom
-  btfss     F_WEEP
-  goto      cmd_w_eeprom_len
-  ;; call      write_eeprom
-  movlw     E_ADDR_INVALID
-  movwf     combuff + .1
-  movlw     .2
-  call      send_answer
-  goto      wait_new_cmd
-
-cmd_w_eeprom_len
-  movf      combuff + .3,w
-  movwf     current_cmdlen
-  bsf       F_WEEP
-  goto      wait_cmd
-
   ;; ** not implemented commands *******
-cmd_reset
-cmd_r_config
-cmd_w_config
+cmd_not_impl
   movlw     E_NOT_IMPL
-  movwf     combuff + .1
-  movlw     .2
+  movwf     combuff + .2
+  movlw     .1
   call      send_answer
   goto      wait_new_cmd
 
@@ -352,7 +319,7 @@ read_flash_segment
   movwf     cnt1
   movlw     b'01011000'
   movwf     STATUS
-  movlw     combuff + .1
+  movlw     combuff + .2
   movwf     FSR
   movf      INDF,w
   movwf     EEADR
@@ -379,8 +346,8 @@ read_flash_segment_next
   decfsz    cnt1,f
   goto      read_flash_segment_loop
   bcf       STATUS,RP1
-  clrf      combuff + .1  ; = E_OK
-  retlw     .2 + .2*FSS   ; bytes to send
+  clrf      combuff + .2  ; = E_OK
+  retlw     .1 + .2*FSS   ; bytes to send
 
   ;; flash write --------
 write_flash_segment
@@ -388,7 +355,7 @@ write_flash_segment
   movwf     cnt1
   movlw     b'01011000'
   movwf     STATUS
-  movlw     combuff + .1
+  movlw     combuff + .2
   movwf     FSR
   movf      INDF,w
   movwf     EEADR
@@ -397,7 +364,7 @@ write_flash_segment
   movwf     EEADRH
 
 write_flash_segment_loop
-  incf      FSR,f               ; load data into EEDAT:EEDATH
+  incf      FSR,f               ; load code word into EEDAT:EEDATH
   movf      INDF,w
   movwf     EEDAT
   incf      FSR,f
@@ -423,13 +390,13 @@ write_flash_segment_next
   decfsz    cnt1,f
   goto      write_flash_segment_loop
   bsf       STATUS,RP0
-  clrw
+  clrw                          ; check if a write error occured
   btfsc     EECON1,WRERR
   movlw     E_FLASH_WERR
   bcf       STATUS,RP1
   bcf       STATUS,RP0
-  movwf     combuff + .1  ; = E_OK
-  retlw     .2            ; bytes to send
+  movwf     combuff + .2  ; = E_OK
+  retlw     .1            ; bytes to send
 
   ;; -------------------------------------
   ;; -------------------------------------