1 | function [phy_tx_start, tx_done, tx_result_out, fsm_state_out] = ... |
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2 | mac_tx_ctrl_b_fsm(... |
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3 | pre_wait_postRxTimer1, ... |
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4 | pre_wait_postRxTimer2, ... |
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5 | pre_wait_postTxTimer1, ... |
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6 | req_zero_nav, ... |
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7 | reset, ... |
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8 | new_tx, ... |
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9 | nav_zero, ... |
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10 | postRxTimer1_done, ... |
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11 | postRxTimer2_done, ... |
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12 | postTxTimer1_done, ... |
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13 | phy_tx_done) |
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14 | |
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15 | persistent fsm_state, fsm_state=xl_state(0, {xlUnsigned, 3, 0}); |
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16 | persistent tx_result, tx_result=xl_state(0, {xlUnsigned, 2, 0}); |
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17 | |
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18 | fsm_state_out = fsm_state; |
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19 | tx_result_out = tx_result; |
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20 | |
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21 | %Inputs: |
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22 | % reset: synchronous reset, forces internal state variables back to default (IDLE state) |
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23 | % new_tx: Software request for new Tx cycle |
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24 | % pre_wait_postRxTimer1: Param requiring this Tx occur after postRxTimer 1 expires |
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25 | % pre_wait_postRxTimer2: Param requiring this Tx occur after postRxTimer 2 expires |
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26 | % pre_wait_postTxTimer1: Param requiring this Tx occur after postTxTimer 1 expires |
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27 | % req_zero_nav: Param requiring this Tx be skipped if NAV is nonzero at Tx time |
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28 | % nav_zero: Indication from MAC if NAV is currently zero (idle) |
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29 | % postRxTimer1_done: Indication from MAC that postRx Timer 1 is done |
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30 | % postRxTimer2_done: Indication from MAC that postRx Timer 2 is done |
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31 | % postTxTimer1_done: Indication from MAC that postTx Timer 1 is done |
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32 | % phy_tx_done: Indication from PHY that PHY Tx is done |
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33 | |
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34 | %Outputs: |
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35 | % backoff_start: Indication to MAC hw to run idle->backoff process |
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36 | % phy_tx_start: Indication to PHY to start Tx |
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37 | % tx_done: Indication to MAC hw that this Tx cycle is complete |
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38 | % tx_result_out: Status of tx_done (did Tx or did not Tx) |
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39 | % fsm_state_out: Value of internal state register (for debugging) |
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40 | |
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41 | %States: |
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42 | % ST_IDLE: Waiting for new Tx from MAC sw |
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43 | % ST_DO_TX: Started PHY Tx, waiting for completion |
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44 | % ST_DEFERRING: Deferral required, wait for BO to finish |
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45 | % ST_POST_TX: Finished Tx, waiting for timeout or Rx |
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46 | |
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47 | |
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48 | ST_IDLE = 0; |
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49 | ST_PRE_TX_WAIT = 1; |
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50 | ST_CHECK_NAV = 2; |
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51 | ST_DO_TX = 3; |
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52 | ST_DONE = 4; |
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53 | |
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54 | TX_RESULT_NONE = 0; |
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55 | TX_RESULT_DID_TX = 1; |
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56 | TX_RESULT_NO_TX = 2; |
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57 | |
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58 | if(reset) |
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59 | phy_tx_start = 0; |
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60 | tx_done = 0; |
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61 | fsm_state = ST_IDLE; |
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62 | tx_result = TX_RESULT_NONE; |
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63 | |
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64 | else |
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65 | switch double(fsm_state) |
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66 | |
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67 | case ST_IDLE |
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68 | phy_tx_start = 0; |
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69 | tx_done = 0; |
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70 | |
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71 | tx_result = TX_RESULT_NONE; |
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72 | |
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73 | if(new_tx) |
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74 | if(pre_wait_postRxTimer1 || pre_wait_postRxTimer2 || pre_wait_postTxTimer1) |
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75 | %Tx scheduled for future, some fixed time after previous Tx/Rx |
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76 | fsm_state = ST_PRE_TX_WAIT; |
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77 | else |
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78 | %No waiting - move on to NAV check, then Tx |
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79 | fsm_state = ST_CHECK_NAV; |
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80 | end |
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81 | else |
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82 | fsm_state = ST_IDLE; |
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83 | end |
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84 | |
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85 | case ST_PRE_TX_WAIT |
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86 | phy_tx_start = 0; |
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87 | tx_done = 0; |
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88 | |
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89 | tx_result = TX_RESULT_NONE; |
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90 | |
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91 | %Stay in PRE_TX_WAIT until the selected timer expires |
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92 | % MAC must take care if using multiple timers/conditions - only |
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93 | % the first will trigger a Tx, the others will expire without effect |
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94 | if( (pre_wait_postRxTimer1 && postRxTimer1_done) || ... |
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95 | (pre_wait_postRxTimer2 && postRxTimer2_done) || ... |
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96 | (pre_wait_postTxTimer1 && postTxTimer1_done)) |
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97 | fsm_state = ST_CHECK_NAV; |
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98 | else |
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99 | fsm_state = ST_PRE_TX_WAIT; |
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100 | end |
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101 | |
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102 | case ST_CHECK_NAV |
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103 | phy_tx_start = 0; |
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104 | tx_done = 0; |
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105 | |
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106 | if( (req_zero_nav && nav_zero) || ~req_zero_nav) |
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107 | %Either don't care about NAV, or NAV was zero - start Tx |
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108 | tx_result = TX_RESULT_DID_TX; |
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109 | fsm_state = ST_DO_TX; |
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110 | else |
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111 | %NAV was non-zero at Tx time - skip Tx |
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112 | tx_result = TX_RESULT_NO_TX; |
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113 | fsm_state = ST_DONE; |
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114 | end |
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115 | |
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116 | case ST_DO_TX |
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117 | phy_tx_start = 1; |
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118 | tx_done = 0; |
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119 | |
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120 | % Stay here until PHY Tx finishes |
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121 | if(phy_tx_done) |
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122 | fsm_state = ST_DONE; |
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123 | else |
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124 | fsm_state = ST_DO_TX; |
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125 | end |
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126 | |
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127 | case ST_DONE |
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128 | phy_tx_start = 0; |
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129 | tx_done = 1; |
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130 | |
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131 | %Previous state set tx_result - leave it alone so downstream |
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132 | % logic can latch it when tx_done goes high |
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133 | |
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134 | fsm_state = ST_IDLE; |
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135 | |
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136 | otherwise |
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137 | %This case should be impossible; mostly here to appease MATLAB |
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138 | phy_tx_start = 0; |
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139 | tx_done = 0; |
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140 | tx_result = TX_RESULT_NONE; |
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141 | fsm_state = ST_IDLE; |
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142 | |
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143 | end %end switch |
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144 | end %end else |
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145 | |
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146 | end %end function |
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147 | |
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