Splitting the Atom back exit forward page 7

RAM used by the Operating System

Address Function
00 Error number in BASIC
01-02 Line number in BASIC, 0 means Direct Mode (as MSB, LSB in Binary, not BCD)
03 BASIC text pointer offset
04 Workspace Stack Pointer
05-06 BASIC text pointer: (5),3 points at character
07 COUNT value
08-0C Random number seed
0D 0E TOP: points to top of BASIC text area.
10 11 Pointer to BASIC error handler
12 BASIC text area MSB (page), normally #29
13 DO / UNTIL stack pointer
14 GOSUB / RETURN stack pointer
15 FOR / NEXT stack pointer
16-24 LSB Integer Workspace stack
25-33  
34-42  
43-51 MSB
  23,24 DIM (free space) pointer
  32,33 DATA pointer for DISATOM
52-6F Arithmetic workspace
70-7F Floating-point workspace (free if FP unused)
80-AF Free
B0-FF COS workspace
  C9 Title string of file to load from tape
  DD *FLOAD flag. Set if bit 7 = 1
  DE,DF Cursor position pointer (start of line)
  E0 Horizontal cursor position, 0 to 1F
  E1 Cursor mask, usually #80
  E6 Page modeflag: neg.=OFF, else no. of lines left
  E7 Lock key flag: 0=inactive, #60 = lock on
  EA Normally 0. If not, then *NOMON engaged
  FE Character NOT sent through VIA to printer
100 13F Input line buffer
140 17F BASIC Input buffer and string operation area
180 1FF Microprocessor Stack
200 201 NMIVEC  
202 203 BRKVEC C9D8
204 205 IRQVEC A000; just RTS
206 207 COMVEC F8EF
208 209 WRCVEC FE52
20A 20B RDCVEC FE94
20C 20D LODVEC FE6E
20E 20E SAVVEC FAE5
210 211 RDRVEC C2AC; just BRK
212 213 STRVEC C2AC; just BRK
214 215 BGTVEC FBEE
216 217 BPTVEC FC7C
218 219 FNDVEC FC38

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