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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html lang="EN">
<link rel="stylesheet" type="text/css" href="stylesheet.css" />
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</script>
<head>
<!--<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">-->
<title>Commodore 64 memory map</title>
<meta name="description" content="A complete memory map of the Commodore 64">
<meta name="author" content="Ingo Hinterding">
<meta charset="UTF-8">
<meta property="og:title" content="Memory Map C64">
<meta property="og:description" content="A complete memory map of the Commodore 64">
<meta name="twitter:card" content="summary"/>
<meta name="twitter:description" content="A complete memory map of the Commodore 64"/>
<meta name="twitter:title" content="C64 Memory Map"/>
<meta name="twitter:creator" content="@awsm9000"/>
</head>
<body>
<center>
<h2>Commodore 64 memory map</h2>
</center>
<div class="container">
<div class="c1-head">Address Hex</div>
<div class="c2-head">Address Dec</div>
<div class="c3-head">Description</div>
</div>
<div class="cspan">$0000-$00FF, 0-256
<br>Zero page
</div>
<div class="container">
<div class="c1">$0000
</div>
<div class="c2">0</div>
<div class="c3">
Processor port data direction register. Bits:
<ul>
<li>
Bit #x: 0 = Bit #x in processor port can only be read; 1 = Bit #x in processor port can be read and written.
</li>
</ul>
Default: $2F, %00101111.
</div>
</div>
<div class="container">
<div class="c1">$0001
</div>
<div class="c2">1
</div>
<div class="c3">Processor port. Bits:
<ul>
<li>
Bits #0-#2: Configuration for memory areas $A000-$BFFF, $D000-$DFFF and $E000-$FFFF. Values:
<ul>
<li>
%x00: RAM visible in all three areas.
</li>
<li>
%x01: RAM visible at $A000-$BFFF and $E000-$FFFF.
</li>
<li>
%x10: RAM visible at $A000-$BFFF; KERNAL ROM visible at $E000-$FFFF.
</li>
<li>
%x11: BASIC ROM visible at $A000-$BFFF; KERNAL ROM visible at $E000-$FFFF.
</li>
<li>
%0xx: Character ROM visible at $D000-$DFFF. (Except for the value %000, see above.)
</li>
<li>
%1xx: I/O area visible at $D000-$DFFF. (Except for the value %100, see above.)
</li>
</ul>
</li>
<li>
Bit #3: Datasette output signal level.
</li>
<li>
Bit #4: Datasette button status; 0 = One or more of PLAY, RECORD, F.FWD or REW pressed; 1 = No button is pressed.
</li>
<li>
Bit #5: Datasette motor control; 0 = On; 1 = Off.
</li>
</ul>
Default: $37, %00110111.
</div>
</div>
<div class="container">
<div class="c1">$0002
</div>
<div class="c2">2</div>
<div class="c3">Unused.</div>
</div>
<div class="container">
<div class="c1">$0003-$0004
</div>
<div class="c2">3-4</div>
<div class="c3">Unused.
<br/> Default: $B1AA, execution address of routine converting floating point to integer.
</div>
</div>
<div class="container">
<div class="c1">$0005-$0006
</div>
<div class="c2">5-6</div>
<div class="c3">Unused.
<br/> Default: $B391, execution address of routine converting integer to floating point.
</div>
</div>
<div class="container">
<div class="c1">$0007
</div>
<div class="c2">7</div>
<div class="c3">Byte being search for during various operations.
<br/> Current digit of number being input.
<br/> Low byte of first integer operand during AND and OR.
<br/> Low byte of integer-format FAC during INT().</div>
</div>
<div class="container">
<div class="c1">$0008
</div>
<div class="c2">8</div>
<div class="c3">Byte being search for during various operations.
<br/> Current byte of BASIC line during tokenization.
<br/> High byte of first integer operand during AND and OR.</div>
</div>
<div class="container">
<div class="c1">$0009
</div>
<div class="c2">9</div>
<div class="c3">Current column number during SPC() and TAB().</div>
</div>
<div class="container">
<div class="c1">$000A
</div>
<div class="c2">10</div>
<div class="c3">LOAD/VERIFY switch. Values:
<ul>
<li>
$00: LOAD.
</li>
<li>
$01-$FF: VERIFY.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$000B
</div>
<div class="c2">11</div>
<div class="c3">Current token during tokenization.
<br/> Length of BASIC line during insertion of line.
<br/> AND/OR switch; $00 = AND; $FF = OR.
<br/> Number of dimensions during array operations.</div>
</div>
<div class="container">
<div class="c1">$000C
</div>
<div class="c2">12</div>
<div class="c3">Switch for array operations. Values:
<ul>
<li>
$00: Operation was not called by DIM.
</li>
<li>
$40-$7F: Operation was called by DIM.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$000D
</div>
<div class="c2">13</div>
<div class="c3">Current expression type. Values:
<ul>
<li>
$00: Numerical.
</li>
<li>
$FF: String.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$000E
</div>
<div class="c2">14</div>
<div class="c3">Current numerical expression type. Bits:
<ul>
<li>
Bit #7: 0 = Floating point; 1 = Integer.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$000F
</div>
<div class="c2">15</div>
<div class="c3">Quotation mode switch during tokenization; Bit #6: 0 = Normal mode; 1 = Quotation mode.
<br/> Quotation mode switch during LIST; $01 = Normal mode; $FE = Quotation mode.
<br/> Garbage collection indicator during memory allocation for string variable; $00-$7F = There was no garbage collection yet; $80 = Garbage collection already took place.</div>
</div>
<div class="container">
<div class="c1">$0010
</div>
<div class="c2">16</div>
<div class="c3">Switch during fetch of variable name. Values:
<ul>
<li>
$00: Integer variables are accepted.
</li>
<li>
$01-$FF: Integer variables are not accepted.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0011
</div>
<div class="c2">17</div>
<div class="c3">GET/INPUT/READ switch. Values:
<ul>
<li>
$00: INPUT.
</li>
<li>
$40: GET.
</li>
<li>
$98: READ.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0012
</div>
<div class="c2">18</div>
<div class="c3">Sign during SIN() and TAN(). Values:
<ul>
<li>
$00: Positive.
</li>
<li>
$FF: Negative.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0013
</div>
<div class="c2">19</div>
<div class="c3">Current I/O device number.
<br/> Default: $00, keyboard for input and screen for output.</div>
</div>
<div class="container">
<div class="c1">$0014-$0015
</div>
<div class="c2">20-21</div>
<div class="c3">Line number during GOSUB, GOTO and RUN.
<br/> Second line number during LIST.
<br/> Memory address during PEEK, POKE, SYS and WAIT.</div>
</div>
<div class="container">
<div class="c1">$0016
</div>
<div class="c2">22</div>
<div class="c3">Pointer to next expression in string stack. Values: $19; $1C; $1F; $22.
<br/> Default: $19.</div>
</div>
<div class="container">
<div class="c1">$0017-$0018
</div>
<div class="c2">23-24</div>
<div class="c3">Pointer to previous expression in string stack.</div>
</div>
<div class="container">
<div class="c1">$0019-$0021
</div>
<div class="c2">25-33</div>
<div class="c3">String stack, temporary area for processing string expressions (9 bytes, 3 entries).</div>
</div>
<div class="container">
<div class="c1">$0022-$0025
</div>
<div class="c2">34-37</div>
<div class="c3">Temporary area for various operations (4 bytes).</div>
</div>
<div class="container">
<div class="c1">$0026-$0029
</div>
<div class="c2">38-41</div>
<div class="c3">Auxiliary arithmetical register for division and multiplication (4 bytes).</div>
</div>
<div class="container">
<div class="c1">$002A
</div>
<div class="c2">42</div>
<div class="c3">Unused.</div>
</div>
<div class="container">
<div class="c1">$002B-$002C
</div>
<div class="c2">43-44</div>
<div class="c3">Pointer to beginning of BASIC area.
<br/> Default: $0801, 2049.</div>
</div>
<div class="container">
<div class="c1">$002D-$002E
</div>
<div class="c2">45-46</div>
<div class="c3">Pointer to beginning of variable area. (End of program plus 1.)</div>
</div>
<div class="container">
<div class="c1">$002F-$0030
</div>
<div class="c2">47-48</div>
<div class="c3">Pointer to beginning of array variable area.</div>
</div>
<div class="container">
<div class="c1">$0031-$0032
</div>
<div class="c2">49-50</div>
<div class="c3">Pointer to end of array variable area.</div>
</div>
<div class="container">
<div class="c1">$0033-$0034
</div>
<div class="c2">51-52</div>
<div class="c3">Pointer to beginning of string variable area. (Grows downwards from end of BASIC area.)</div>
</div>
<div class="container">
<div class="c1">$0035-$0036
</div>
<div class="c2">53-54</div>
<div class="c3">Pointer to memory allocated for current string variable.</div>
</div>
<div class="container">
<div class="c1">$0037-$0038
</div>
<div class="c2">55-56</div>
<div class="c3">Pointer to end of BASIC area.
<br/> Default: $A000, 40960.</div>
</div>
<div class="container">
<div class="c1">$0039-$003A
</div>
<div class="c2">57-58</div>
<div class="c3">Current BASIC line number. Values:
<ul>
<li>
$0000-$F9FF, 0-63999: Line number.
</li>
<li>
$FF00-$FFFF: Direct mode, no BASIC program is being executed.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$003B-$003C
</div>
<div class="c2">59-60</div>
<div class="c3">Current BASIC line number for CONT.</div>
</div>
<div class="container">
<div class="c1">$003D-$003E
</div>
<div class="c2">61-62</div>
<div class="c3">Pointer to next BASIC instruction for CONT. Values:
<ul>
<li>
$0000-$00FF: CONT'ing is not possible.
</li>
<li>
$0100-$FFFF: Pointer to next BASIC instruction.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$003F-$0040
</div>
<div class="c2">63-64</div>
<div class="c3">BASIC line number of current DATA item for READ.</div>
</div>
<div class="container">
<div class="c1">$0041-$0042
</div>
<div class="c2">65-66</div>
<div class="c3">Pointer to next DATA item for READ.</div>
</div>
<div class="container">
<div class="c1">$0043-$0044
</div>
<div class="c2">67-68</div>
<div class="c3">Pointer to input result during GET, INPUT and READ.</div>
</div>
<div class="container">
<div class="c1">$0045-$0046
</div>
<div class="c2">69-70</div>
<div class="c3">Name and type of current variable. Bits:
<ul>
<li>
$0045 bits #0-#6: First character of variable name.
</li>
<li>
$0046 bits #0-#6: Second character of variable name; $00 = Variable name consists of only one character.
</li>
<li>
$0045 bit #7 and $0046 bit #7:
<ul>
<li>
%00: Floating-point variable.
</li>
<li>
%01: String variable.
</li>
<li>
%10: FN function, created with DEF FN.
</li>
<li>
%11: Integer variable.
</li>
</ul>
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0047-$0048
</div>
<div class="c2">71-72</div>
<div class="c3">Pointer to value of current variable or FN function.</div>
</div>
<div class="container">
<div class="c1">$0049-$004A
</div>
<div class="c2">73-74</div>
<div class="c3">Pointer to value of current variable during LET.
<br/> Value of second and third parameter during WAIT.
<br/> Logical number and device number during OPEN.
<br/> $0049, 73: Logical number of CLOSE.
<br/> Device number of LOAD, SAVE and VERIFY.</div>
</div>
<div class="container">
<div class="c1">$004B-$004C
</div>
<div class="c2">75-76</div>
<div class="c3">Temporary area for saving original pointer to current BASIC instruction during GET, INPUT and READ.
</div>
</div>
<div class="container">
<div class="c1">$004D
</div>
<div class="c2">77</div>
<div class="c3">Comparison operator indicator. Bits:
<ul>
<li>
Bit #1: 1 = ">" (greater than) is present in expression.
</li>
<li>
Bit #2: 1 = "=" (equal to) is present in expression.
</li>
<li>
Bit #3: 1 = "<" (less than) is present in expression.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$004E-$004F
</div>
<div class="c2">78-79</div>
<div class="c3">Pointer to current FN function.
</div>
</div>
<div class="container">
<div class="c1">$0050-$0051
</div>
<div class="c2">80-81</div>
<div class="c3">Pointer to current string variable during memory allocation.</div>
</div>
<div class="container">
<div class="c1">$0052
</div>
<div class="c2">82</div>
<div class="c3">Unused.</div>
</div>
<div class="container">
<div class="c1">$0053
</div>
<div class="c2">83</div>
<div class="c3">Step size of garbage collection. Values: $03; $07.</div>
</div>
<div class="container">
<div class="c1">$0054-$0056
</div>
<div class="c2">84-86</div>
<div class="c3">JMP ABS machine instruction, jump to current BASIC function.
<br/> $0055-$0056, 85-86: Execution address of current BASIC function.</div>
</div>
<div class="container">
<div class="c1">$0057-$005B
</div>
<div class="c2">87-91</div>
<div class="c3">Arithmetic register #3 (5 bytes).
</div>
</div>
<div class="container">
<div class="c1">$005C-$0060
</div>
<div class="c2">92-96</div>
<div class="c3">Arithmetic register #4 (5 bytes).
</div>
</div>
<div class="container">
<div class="c1">$0061-$0065
</div>
<div class="c2">97-101</div>
<div class="c3">FAC, arithmetic register #1 (5 bytes).</div>
</div>
<div class="container">
<div class="c1">$0066
</div>
<div class="c2">102</div>
<div class="c3">Sign of FAC. Bits:
<ul>
<li>
Bit #7: 0 = Positive; 1 = Negative.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0067
</div>
<div class="c2">103</div>
<div class="c3">Number of degrees during polynomial evaluation.
</div>
</div>
<div class="container">
<div class="c1">$0068
</div>
<div class="c2">104</div>
<div class="c3">Temporary area for various operations.
</div>
</div>
<div class="container">
<div class="c1">$0069-$006D
</div>
<div class="c2">105-109</div>
<div class="c3">ARG, arithmetic register #2 (5 bytes).</div>
</div>
<div class="container">
<div class="c1">$006E
</div>
<div class="c2">110</div>
<div class="c3">Sign of ARG. Bits:
<ul>
<li>
Bit #7: 0 = Positive; 1 = Negative.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$006F-$0070
</div>
<div class="c2">111-112</div>
<div class="c3">Pointer to first string expression during string comparison.</div>
</div>
<div class="container">
<div class="c1">$0071-$0072
</div>
<div class="c2">113-114</div>
<div class="c3">Auxiliary pointer during array operations.
<br/> Temporary area for saving original pointer to current BASIC instruction during VAL().
<br/> Pointer to current item of polynomial table during polynomial evaluation.
</div>
</div>
<div class="container">
<div class="c1">$0073-$008A
</div>
<div class="c2">115-138</div>
<div class="c3">CHRGET. Machine code routine to read next byte from BASIC program or direct command (24 bytes).
<br/> $0079, 121: CHRGOT. Read current byte from BASIC program or direct command.
<br/> $007A-$007B, 122-123: Pointer to current byte in BASIC program or direct command.
</div>
</div>
<div class="container">
<div class="c1">$008B-$008F
</div>
<div class="c2">139-143</div>
<div class="c3">Previous result of RND().
</div>
</div>
<div class="container">
<div class="c1">$0090
</div>
<div class="c2">144</div>
<div class="c3">Value of ST variable, device status for serial bus and datasette input/output. Serial bus bits:
<ul>
<li>
Bit #0: Transfer direction during which the timeout occured; 0 = Input; 1 = Output.
</li>
<li>
Bit #1: 1 = Timeout occurred.
</li>
<li>
Bit #4: 1 = VERIFY error occurred (only during VERIFY), the file read from the device did not match that in the memory.
</li>
<li>
Bit #6: 1 = End of file has been reached.
</li>
<li>
Bit #7: 1 = Device is not present.
</li>
</ul>
Datasette bits:
<ul>
<li>
Bit #2: 1 = Block is too short (shorter than 192 bytes).
</li>
<li>
Bit #3: 1 = Block is too long (longer than 192 bytes).
</li>
<li>
Bit #4: 1 = Not all bytes read with error during pass 1 could be corrected during pass 2, or a VERIFY error occurred, the file read from the device did not match that in the memory.
</li>
<li>
Bit #5: 1 = Checksum error occurred.
</li>
<li>
Bit #6: 1 = End of file has been reached (only during reading data files).
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0091
</div>
<div class="c2">145</div>
<div class="c3">Stop key indicator. Values:
<ul>
<li>
$7F: Stop key is pressed.
</li>
<li>
$FF: Stop key is not pressed.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0092
</div>
<div class="c2">146</div>
<div class="c3">Unknown. (Timing constant during datasette input.)</div>
</div>
<div class="container">
<div class="c1">$0093
</div>
<div class="c2">147</div>
<div class="c3">LOAD/VERIFY switch. Values:
<ul>
<li>
$00: LOAD.
</li>
<li>
$01-$FF: VERIFY.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0094
</div>
<div class="c2">148</div>
<div class="c3">Serial bus output cache status. Bits:
<ul>
<li>
Bit #7: 1 = Output cache dirty, must transfer cache contents upon next output to serial bus.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$0095
</div>
<div class="c2">149</div>
<div class="c3">Serial bus output cache, previous byte to be sent to serial bus.</div>
</div>
<div class="container">
<div class="c1">$0096
</div>
<div class="c2">150</div>
<div class="c3">Unknown. (End of tape indicator during datasette input/output.)</div>
</div>
<div class="container">
<div class="c1">$0097
</div>
<div class="c2">151</div>
<div class="c3">Temporary area for saving original value of Y register during input from RS232.
<br/> Temporary area for saving original value of X register during input from datasette.
</div>
</div>
<div class="container">
<div class="c1">$0098
</div>
<div class="c2">152</div>
<div class="c3">Number of files currently open. Values: $00-$0A, 0-10.</div>
</div>
<div class="container">
<div class="c1">$0099
</div>
<div class="c2">153</div>
<div class="c3">Current input device number.
<br/> Default: $00, keyboard.</div>
</div>
<div class="container">
<div class="c1">$009A
</div>
<div class="c2">154</div>
<div class="c3">Current output device number.
<br/> Default: $03, screen.</div>
</div>
<div class="container">
<div class="c1">$009B
</div>
<div class="c2">155</div>
<div class="c3">Unknown. (Parity bit during datasette input/output.)</div>
</div>
<div class="container">
<div class="c1">$009C
</div>
<div class="c2">156</div>
<div class="c3">Unknown. (Byte ready indicator during datasette input/output.)</div>
</div>
<div class="container">
<div class="c1">$009D
</div>
<div class="c2">157</div>
<div class="c3">System error display switch. Bits:
<ul>
<li>
Bit #6: 0 = Suppress I/O error messages; 1 = Display them.
</li>
<li>
Bit #7: 0 = Suppress system messages; 1 = Display them.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$009E
</div>
<div class="c2">158</div>
<div class="c3">Byte to be put into output buffer during RS232 and datasette output.
<br/> Block header type during datasette input/output.
<br/> Length of file name during datasette input/output.
<br/> Error counter during LOAD from datasette. Values: $00-$3E, 0-62.</div>
</div>
<div class="container">
<div class="c1">$009F
</div>
<div class="c2">159</div>
<div class="c3">Auxiliary counter for writing file name into datasette buffer.
<br/> Auxiliary counter for comparing requested file name with file name read from datasette during datasette input.
<br/> Error correction counter during LOAD from datasette. Values: $00-$3E, 0-62.
</div>
</div>
<div class="container">
<div class="c1">$00A0-$00A2
</div>
<div class="c2">160-162</div>
<div class="c3">Value of TI variable, time of day, increased by 1 every 1/60 second (on PAL machines). Values: $000000-$4F19FF, 0-518399 (on PAL machines).
</div>
</div>
<div class="container">
<div class="c1">$00A3
</div>
<div class="c2">163</div>
<div class="c3">EOI switch during serial bus output. Bits:
<ul>
<li>
Bit #7: 0 = Send byte right after handshake; 1 = Do EOI delay first.
</li>
</ul>
Bit counter during datasette output.</div>
</div>
<div class="container">
<div class="c1">$00A4
</div>
<div class="c2">164</div>
<div class="c3">Byte buffer during serial bus input.
<br/> Parity during datasette input/output.</div>
</div>
<div class="container">
<div class="c1">$00A5
</div>
<div class="c2">165</div>
<div class="c3">Bit counter during serial bus input/output.
<br/> Counter for sync mark during datasette output.</div>
</div>
<div class="container">
<div class="c1">$00A6
</div>
<div class="c2">166</div>
<div class="c3">Offset of current byte in datasette buffer.
</div>
</div>
<div class="container">
<div class="c1">$00A7
</div>
<div class="c2">167</div>
<div class="c3">Bit buffer during RS232 input.</div>
</div>
<div class="container">
<div class="c1">$00A8
</div>
<div class="c2">168</div>
<div class="c3">Bit counter during RS232 input.</div>
</div>
<div class="container">
<div class="c1">$00A9
</div>
<div class="c2">169</div>
<div class="c3">Stop bit switch during RS232 input. Values:
<ul>
<li>
$00: Data bit.
</li>
<li>
$01-$FF: Stop bit.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$00AA
</div>
<div class="c2">170</div>
<div class="c3">Byte buffer during RS232 input.</div>
</div>
<div class="container">
<div class="c1">$00AB
</div>
<div class="c2">171</div>
<div class="c3">Parity during RS232 input.
<br/> Computed block checksum during datasette input.</div>
</div>
<div class="container">
<div class="c1">$00AC-$00AD
</div>
<div class="c2">172-173</div>
<div class="c3">Start address for SAVE to serial bus.
<br/> Pointer to current byte during SAVE to serial bus or datasette.
<br/> Pointer to line in screen memory to be scrolled during scrolling the screen.
</div>
</div>
<div class="container">
<div class="c1">$00AE-$00AF
</div>
<div class="c2">174-175</div>
<div class="c3">Load address read from input file and pointer to current byte during LOAD/VERIFY from serial bus.
<br/> End address after LOAD/VERIFY from serial bus or datasette.
<br/> End address for SAVE to serial bus or datasette.
<br/> Pointer to line in Color RAM to be scrolled during scrolling the screen.</div>
</div>
<div class="container">
<div class="c1">$00B0-$00B1
</div>
<div class="c2">176-177</div>
<div class="c3">Unknown.</div>
</div>
<div class="container">
<div class="c1">$00B2-$00B3
</div>
<div class="c2">178-179</div>
<div class="c3">Pointer to datasette buffer.
<br/> Default: $033C, 828.</div>
</div>
<div class="container">
<div class="c1">$00B4
</div>
<div class="c2">180</div>
<div class="c3">Bit counter and stop bit switch during RS232 output. Bits:
<ul>
<li>
Bits #0-#6: Bit count.
</li>
<li>
Bit #7: 0 = Data bit; 1 = Stop bit.
</li>
</ul>
Bit counter during datasette input/output.</div>
</div>
<div class="container">
<div class="c1">$00B5
</div>
<div class="c2">181</div>
<div class="c3">Bit buffer (in bit #2) during RS232 output.
</div>
</div>
<div class="container">
<div class="c1">$00B6
</div>
<div class="c2">182</div>
<div class="c3">Byte buffer during RS232 output.
</div>
</div>
<div class="container">
<div class="c1">$00B7
</div>
<div class="c2">183</div>
<div class="c3">Length of file name or disk command; first parameter of LOAD, SAVE and VERIFY or fourth parameter of OPEN. Values:
<ul>
<li>
$00: No parameter.
</li>
<li>
$01-$FF: Parameter length.
</li>
</ul>
</div>
</div>
<div class="container">
<div class="c1">$00B8
</div>
<div class="c2">184</div>
<div class="c3">Logical number of current file.</div>
</div>
<div class="container">
<div class="c1">$00B9
</div>
<div class="c2">185</div>
<div class="c3">Secondary address of current file.
</div>
</div>
<div class="container">
<div class="c1">$00BA
</div>
<div class="c2">186</div>
<div class="c3">Device number of current file.</div>
</div>
<div class="container">
<div class="c1">$00BB-$00BC
</div>
<div class="c2">187-188</div>
<div class="c3">Pointer to current file name or disk command; first parameter of LOAD, SAVE and VERIFY or fourth parameter of OPEN.</div>
</div>
<div class="container">
<div class="c1">$00BD
</div>
<div class="c2">189</div>
<div class="c3">Parity during RS232 output.
<br/> Byte buffer during datasette input/output.</div>
</div>
<div class="container">
<div class="c1">$00BE
</div>
<div class="c2">190</div>
<div class="c3">Block counter during datasette input/output.
</div>
</div>
<div class="container">
<div class="c1">$00BF
</div>
<div class="c2">191</div>
<div class="c3">Unknown.</div>
</div>
<div class="container">
<div class="c1">$00C0