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annotate level2/modules/kernel/fdelram.asm @ 3198:734862561313

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3rdparty/packages: Rename particularly cryptic folder names
author Tormod Volden <debian.tormod@gmail.com>
date Sat, 03 Jun 2017 10:34:39 +0200
parents 039ddb7c8ad7
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1 **************************************************
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1451bc7ef0b9 Updates source comments
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2 * System Call: F$DelRAM
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3 *
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4 * Function: Deallocate RAM blocks
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5 *
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6 * Input: B = Number of blocks
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7 * X = Beginning block number
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8 *
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9 * Output: None
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10 *
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11 * Error: CC = C bit set; B = error code
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12 *
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13 FDelRAM ldb R$B,u # of blocks to de-allocate
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14 beq DelRAM.2 if none, exit
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15 ldd <D.BlkMap+2 get end of the block map
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16 subd <D.BlkMap subtract out start of the block map
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17 subd R$X,u take out starting block number
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18 bls DelRAM.2 exit if the starting block is ># of blocks available
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19 tsta check high byte of RAM #
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20 bne DelRAM.0 if not zero, skip it
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21 cmpb R$B,u check against size of the block
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22 bhs DelRAM.0 if size is >RAM available
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23 stb R$B,u save actual # of blocks deleted
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24 DelRAM.0 ldx <D.BlkMap get start address of the block map
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25 ldd R$X,u starting address of the RAM to de-allocate
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26 leax d,x slower, but smaller than ADDR
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27 ldb R$B,u get actual # of blocks to de-allocate
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28 DelRAM.1 equ *
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29 IFNE H6309
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30 aim #^RAMinUse,,x+ set to RAM not in use
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31 ELSE
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32 lda ,x
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33 anda #^RAMinUse
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34 sta ,x+
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35 ENDC
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36 decb count down a block
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37 bne DelRAM.1 continue
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38 DelRAM.2 clrb and exit
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039ddb7c8ad7 l2 kernel: Remove tabs and trailing whitespace, align comments
Neal Crook <foofoobedoo@gmail.com>
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39 rts