annotate src/external_flash.asm @ 177:67db1f6d3787

Merge
author heinrichsweikamp
date Tue, 07 Oct 2014 08:42:38 +0200
parents 05f2100d2eb8
children 653a3ab08062
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1 ;=============================================================================
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2 ;
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3 ; File external_flash.asm
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4 ;
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5 ; External flash
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6 ;
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7 ; Copyright (c) 2011, JD Gascuel, HeinrichsWeikamp, all right reserved.
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8 ;=============================================================================
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9 ; HISTORY
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10 ; 2011-08-12 : [mH] creation
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11
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12 #include "ostc3.inc"
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13 #include "wait.inc"
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14
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15 basic CODE
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16 ;=============================================================================
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17
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18 global incf_ext_flash_address_p1
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19 incf_ext_flash_address_p1: ; Increase by one
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20 movlw .1
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21
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22 global incf_ext_flash_address0
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23 incf_ext_flash_address0:
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24 addwf ext_flash_address+0,F ; increase address
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25 movlw d'0'
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26 addwfc ext_flash_address+1,F
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27 addwfc ext_flash_address+2,F
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28
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29 movlw 0x40
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30 cpfseq ext_flash_address+2 ; at address 40FFFF?
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31 return ; No, return
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32 ; clrf ext_flash_address+0
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33 ; clrf ext_flash_address+1
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34 clrf ext_flash_address+2 ; Yes, rollover to 0x000000
0
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35 return
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36
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37 global incf_ext_flash_address0_p1_0x20
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38 incf_ext_flash_address0_p1_0x20: ; Increase by one
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39 movlw .1
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40
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41 global incf_ext_flash_address0_0x20
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42 incf_ext_flash_address0_0x20: ; with roll-over at 0x200000 to 0x000000
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43 addwf ext_flash_address+0,F ; increase address
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44 movlw d'0'
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45 addwfc ext_flash_address+1,F
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46 addwfc ext_flash_address+2,F
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47
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48 movlw 0x20
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49 cpfseq ext_flash_address+2 ; at address 0x200000?
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50 return ; No, return
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51 ; clrf ext_flash_address+0
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52 ; clrf ext_flash_address+1
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53 clrf ext_flash_address+2 ; Yes, rollover to 0x000000
0
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54 return
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55
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56 global decf_ext_flash_address0
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57 decf_ext_flash_address0:
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58 subwf ext_flash_address+0,F ; decrease address: do a 16-8bits substract.
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59 movlw d'0'
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60 subwfb ext_flash_address+1,F
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61 movlw d'0'
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62 subwfb ext_flash_address+2,F
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63
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64 btfss ext_flash_address+2,7 ; Rollover to 0xFFFFFF?
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65 return ; No, return
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66 clrf ext_flash_address+2 ; Set to 0x00FFFFF
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67 setf ext_flash_address+1
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68 setf ext_flash_address+0
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69 return
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70
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71 global ext_flash_power_down
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72 ext_flash_power_down:
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73 movlw 0x04 ; Write disable
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74 rcall write_spi
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75 bsf flash_ncs ; CS=1
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76 return
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77
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78 global ext_flash_byte_read_plus ; Return data read in WREG and SSP2BUF and
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79 ext_flash_byte_read_plus: ; increase address after read
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80 rcall ext_flash_byte_read
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81 movwf temp1 ; store received data
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82 bra incf_ext_flash_address_p1 ; +1 and return
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83
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84 global ext_flash_byte_read_plus_0x20; Return data read in WREG and SSP2BUF and
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85 ext_flash_byte_read_plus_0x20: ; increase address after read with banking at 0x200000
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86 rcall ext_flash_byte_read
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87 movwf temp1 ; store received data
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88 bra incf_ext_flash_address0_p1_0x20 ;+1 and return
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89
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90
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91 global ext_flash_byte_read ; Return data read in WREG
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92 ext_flash_byte_read:
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93 movlw 0x03 ; Read command
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94 rcall write_spi
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95 rcall ext_flash_write_address ; Write 24bit address ext_flash_address:3 via SPI
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96 rcall write_spi ; Dummy write to read data into WREG
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97 bsf flash_ncs ; CS=1
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98 movwf temp1
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99 return ; Return data read in WREG and temp1
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100
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101 ext_flash_write_address: ; Write 24bit address ext_flash_address:3 via SPI
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102 movf ext_flash_address+2,W ; 24Bit Address
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103 rcall write_spi
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104 movf ext_flash_address+1,W
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105 rcall write_spi
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106 movf ext_flash_address+0,W
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107 bra write_spi ; And return....
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108
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109 global ext_flash_read_block_start ; Return data read in WREG
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110 ext_flash_read_block_start:
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111 movlw 0x03 ; Read command
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112 rcall write_spi
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113 rcall ext_flash_write_address ; Write 24bit address ext_flash_address:3 via SPI
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114 rcall write_spi ; Dummy write to read data into WREG
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115 return ; Return data read in WREG
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116
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117 global ext_flash_read_block ; Return data read in WREG
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118 ext_flash_read_block:
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119 rcall incf_ext_flash_address_p1 ; Increase address +1
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120 bra write_spi1 ; Dummy write to read data into WREG and return
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121
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122 global ext_flash_read_block_stop ; Return data read in WREG
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123 ext_flash_read_block_stop:
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124 bsf flash_ncs ; CS=1
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125 return ; NO data in WREG
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126
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127 global write_byte_ext_flash_plus_header
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128 write_byte_ext_flash_plus_header: ; Write from WREG and increase address after write
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129 movwf temp1 ; store data
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130 ; test if write is done at first byte of 4kB block
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131 ; if yes -> delete 4kB block first
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132 tstfsz ext_flash_address+0 ; at 0x00?
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133 bra write_byte_ext_flash_plus_h1 ; No, normal Write
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134
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135 movf ext_flash_address+1,W
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136 andlw 0x0F ; Mask lower nibble
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137 tstfsz WREG ; at 0x.0?
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138 bra write_byte_ext_flash_plus_h1; No, normal Write
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139
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140 ; At beginning of 4kB block -> rease first!
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141 rcall ext_flash_erase4kB ; Erases 4kB sector @ext_flash_address:3
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142 write_byte_ext_flash_plus_h1:
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143 movf temp1,W
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144 rcall ext_flash_byte_write ; Write the byte
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145 bra incf_ext_flash_address_p1 ; +1 and return
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146
6
13cda523891f bugfix: dive length in normal header
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147 global write_byte_ext_flash_plus_nocnt
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148 write_byte_ext_flash_plus_nocnt: ; Write from WREG and increase address after write with banking at 0x200000
13cda523891f bugfix: dive length in normal header
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149 movwf temp1 ; store data
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150 bra write_byte_ext_flash_plus2
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151
0
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152 global write_byte_ext_flash_plus ; Write from WREG and increase address after write with banking at 0x200000
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153 write_byte_ext_flash_plus:
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154 movwf temp1 ; store data
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155
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156 ; First, increase dive length counter
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157 incf ext_flash_dive_counter+0,F
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158 movlw .0
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159 addwfc ext_flash_dive_counter+1,F
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160 addwfc ext_flash_dive_counter+2,F ; 24bit++
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161
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13cda523891f bugfix: dive length in normal header
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162 write_byte_ext_flash_plus2:
0
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163 ; Now test if write is done at first byte of 4kB block
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164 ; if yes -> delete 4kB block first
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165 tstfsz ext_flash_address+0 ; at 0x00?
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166 bra write_byte_ext_flash_plus1 ; No, normal Write
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167
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168 movf ext_flash_address+1,W
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169 andlw 0x0F ; Mask lower nibble
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170 tstfsz WREG ; at 0x.0?
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171 bra write_byte_ext_flash_plus1 ; No, normal Write
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172
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173 ; At beginning of 4kB block -> erase first!
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174 rcall ext_flash_erase4kB ; Erases 4kB sector @ext_flash_address:3
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175 write_byte_ext_flash_plus1:
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176 movf temp1,W
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177 rcall ext_flash_byte_write ; Write the byte
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178 bra incf_ext_flash_address0_p1_0x20 ; +1 and roll over at 0x200000 to 0x000000 and return
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179
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180 global ext_flash_byte_write ; Write from WREG
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181 ext_flash_byte_write:
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182 movwf temp1 ; store data byte
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183 bsf flash_ncs ; CS=1
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184 movlw 0x06 ; WREN command
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185 rcall write_spi
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186 bsf flash_ncs ; CS=1
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187 movlw 0x02 ; Write command
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188 rcall write_spi
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189 rcall ext_flash_write_address ; Write 24bit address ext_flash_address:3 via SPI
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190 movf temp1,W ; load data byte
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191 rcall write_spi ; write one byte of data!
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192 bsf flash_ncs ; CS=1
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193 return
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194
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195 global ext_flash_disable_protection ; Disable write protection
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196 ext_flash_disable_protection:
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197 bsf flash_ncs ; CS=1
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198 movlw 0x50 ; EWSR command
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199 rcall write_spi
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200 bsf flash_ncs ; CS=1
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201
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202 movlw 0x01 ; WRSR command
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203 rcall write_spi
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204 movlw b'00000000' ; New status
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205 rcall write_spi
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206 bsf flash_ncs ; CS=1
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207 return
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208
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209 global ext_flash_enable_protection
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210 ext_flash_enable_protection:
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211 bsf flash_ncs ; CS=1
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212 movlw 0x50 ; EWSR command
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213 rcall write_spi
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214 bsf flash_ncs ; CS=1
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215
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216 movlw 0x01 ; WRSR command
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217 rcall write_spi
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218 movlw b'00011100' ; New status (Write protect on)
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219 rcall write_spi
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220 bsf flash_ncs ; CS=1
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221 return
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222
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223
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224 global ext_flash_erase4kB ; Erases 4kB sector
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225 ext_flash_erase4kB:
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226 bsf flash_ncs ; CS=1
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227 movlw 0x06 ; WREN command
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228 rcall write_spi
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229 bsf flash_ncs ; CS=1
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230 movlw 0x20 ; Sector erase command
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231 rcall write_spi
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232 rcall ext_flash_write_address ; Write 24bit address ext_flash_address:3 via SPI
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233 bsf flash_ncs ; CS=1
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234 ; bra ext_flash_wait_write ; Wait for write... and return
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235 ext_flash_wait_write:
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236 WAITMS d'1' ; TBE=25ms...
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237 movlw 0x05 ; RDSR command
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238 rcall write_spi ; Read status
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239 rcall write_spi ; Read status into WREG
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240 bsf flash_ncs ; CS=1
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241 btfsc SSP2BUF,0 ; Write operation in process?
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242 bra ext_flash_wait_write ; Yes, wait more..
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243 return
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244
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245 global ext_flash_erase_logbook ; erases logbook memory (000000h -> 2FFFFFh -> 3MByte)
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246 ext_flash_erase_logbook:
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247 bsf flash_ncs ; CS=1
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248 clrf ext_flash_address+0
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249 clrf ext_flash_address+1
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250 clrf ext_flash_address+2
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251
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252 movlw d'48'
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253 movwf temp1 ; 48*64kB=917504 Bytes
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254 ext_flash_erase_logbook_loop:
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255 movlw 0x06 ; WREN command
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256 rcall write_spi
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257 bsf flash_ncs ; CS=1
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258 movlw 0xD8 ; 64kB erase command
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259 rcall write_spi
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260 rcall ext_flash_write_address ; Write 24bit address ext_flash_address:3 via SPI
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261 bsf flash_ncs ; CS=1
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262 rcall ext_flash_wait_write ; Wait for write...
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263
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264 incf ext_flash_address+2,F ; 64kB ahead
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265 decfsz temp1,F
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266 bra ext_flash_erase_logbook_loop
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267 return
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268
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269
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270 write_spi: ; With data in WREG...
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271 bcf flash_ncs ; CS
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272 global write_spi1
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273 write_spi1: ; With data in WREG...
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274 bcf SSP2STAT,WCOL ; Clear flag
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275 movwf SSP2BUF ; Write to buffer
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276 btfsc SSP2STAT,WCOL ; Was buffer full?
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277 bra write_spi1 ; Yes, try again
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278
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279 write_spi2: ; Wait for write command
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280 btfss SSP2STAT, BF ; Buffer full?
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281 bra write_spi2 ; No, wait.
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282 movf SSP2BUF,W
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283 return ; Returns RX data in WREG and SSP2BUF
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284
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285 END