Routines 
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The address of this routine is found in the table of addresses.
This subroutine gives a 'last value' on the top of the calculator stack that is the result of converting a number given in the form xEm, where m is a positive or negative integer. The subroutine is entered with x at the top of the calculator stack and m in the A register.
The method used is to find the absolute value of m, say p, and to multiply or divide x by 10↑p according to whether m is positive or negative.
To achieve this, p is shifted right until it is zero, and x is multiplied or divided by 10↑(2↑n) for each set bit b(n) of p. Since p is never much more than 39, bits 6 and 7 of p will not normally be set.


e_to_fp  11599  RLCA  Test the sign of m by rotating bit 7 of A into the carry without changing A.  
11600  RRCA  
11601  JR NC,E_SAVE  Jump if m is positive.  
11603  CPL  Negate m in A without disturbing the carry flag.  
11604  INC A  
E_SAVE  11605  PUSH AF  Save m in A briefly.  
11606  LD HL,23698  This is MEMBOT; a sign flag is now stored in the first byte of mem0, i.e. 0 for '+' and 1 for ''.  
11609  CALL FP_0_1  
11612  RST 40  The stack holds x.  
11613  DEFB 164  stk_ten: x, 10  
11614  DEFB 56  end_calc: x, 10  
11615  POP AF  Restore m in A.  
E_LOOP  11616  SRL A  In the loop, shift out the next bit of m, modifying the carry and zero flags appropriately; jump if carry reset.  
11618  JR NC,E_TST_END  
11620  PUSH AF  Save the rest of m and the flags.  
11621  RST 40  The stack holds x' and 10↑(2↑n), where x' is an interim stage in the multiplication of x by 10↑m, and n=0, 1, 2, 3, 4 or 5.  
11622  DEFB 193  st_mem_1: (10↑(2↑n) is copied to mem1)  
11623  DEFB 224  get_mem_0: x', 10↑(2↑n), (1/0)  
11624  DEFB 0  jump_true to E_DIVSN: x', 10↑(2↑n)  
11625  DEFB 4  
11626  DEFB 4  multiply: x'*10↑(2↑n)=x"  
11627  DEFB 51  jump to E_FETCH: x''  
11628  DEFB 2  
E_DIVSN  11629  DEFB 5  division: x/10↑(2↑n)=x'' (x'' is x'*10↑(2↑n) or x'/10↑(2↑n) according as m is '+' or '')  
E_FETCH  11630  DEFB 225  get_mem_1: x'', 10↑(2↑n)  
11631  DEFB 56  end_calc: x'', 10↑(2↑n)  
11632  POP AF  Restore the rest of m in A, and the flags.  
E_TST_END  11633  JR Z,E_END  Jump if m has been reduced to zero.  
11635  PUSH AF  Save the rest of m in A.  
11636  RST 40  x'', 10↑(2↑n)  
11637  DEFB 49  duplicate: x'', 10↑(2↑n), 10↑(2↑n)  
11638  DEFB 4  multiply: x'', 10↑(2↑(n+1))  
11639  DEFB 56  end_calc: x'', 10↑(2↑(n+1))  
11640  POP AF  Restore the rest of m in A.  
11641  JR E_LOOP  Jump back for all bits of m.  
E_END  11643  RST 40  Use the calculator to delete the final power of 10 reached leaving the 'last value' x*10↑m on the stack.  
11644  DEFB 2  delete  
11645  DEFB 56  end_calc  
11646  RET 
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