Opcodes

Opcodes

Opcodes used by the HP-35s (Emulation) software.

Each instruction is stored in a block of 3 bytes.

On the simulator, if you save the state and check the produced *.ep file, the programs are stored at the very end of the file, in reverse order (last 3 bytes are the 1st hex representation of an instruction).

Example:

Byte	Description
01	is apparently a multi purposes bitset of flags
01	is a parameter, here it means A (LBL B would be 01 02 7B)
7B	is the opcode of LBL

Instruction 01

Single Instructions

01 00 oc

01: instruction
00: zero byte (no operands)
oc: opcode

Instruction	Hexcode
+/-	01 00 2f
+	01 00 32
-	01 00 33
*	01 00 34
/	01 00 35
!	01 00 3c
sqrt	01 00 3f
xroot	01 00 57
1000	01 00 0f
1,000	01 00 0e
1/x	01 00 3b
10^x	01 00 37
%	01 00 41
pi	01 00 2d
Z+	01 00 5b
Z-	01 00 5c
zx	01 00 25
Zx	01 00 28
Zx^2	01 00 2a
Zxy	01 00 2c
zy	01 00 26
Zy	01 00 29
Zy^2	01 00 2b
ACOS	01 00 47
ACOSH	01 00 4c
ASIN	01 00 46
ASINH	01 00 4d
ATAN	01 00 48
ATANH	01 00 4e
ALG	01 00 04
ALL	01 00 13
AND	01 00 a6
b	01 00 1f
BIN	01 00 08
/c	01 00 31
->°C	01 00 65
%CHG	01 00 55
CLZ	01 00 19
CLx	01 00 17
CLVARS	01 00 18
CLSTK	01 00 1A
->CM	01 00 67
COS	01 00 44
DEC	01 00 05
DEG	01 00 09
->DEG	01 00 61
ENG	01 00 12
<-ENG	01 00 94
ENG->	01 00 93
ENTER	01 00 01
e^x	01 00 36
->°F	01 00 66
FP	01 00 53
->GAL	01 00 6A
GRAD	01 00 0b
HEX	01 00 06
->HMS	01 00 60
HMS->	01 00 5f
->IN	01 00 68
INT/	01 00 50
INTG	01 00 52
IP	01 00 54
->KG	01 00 63
->KM	01 00 5e
->L	01 00 69
LASTx	01 00 97
->LB	01 00 64
LN	01 00 38
LOG	01 00 39
m	01 00 1e
->MILE	01 00 5d
n	01 00 27
NAND	01 00 ab
nCr	01 00 58
NOR	01 00 aa
NOT	01 00 a9
nPr	01 00 59
OCT	01 00 07
OR	01 00 a8
PSE	01 00 78
rta	01 00 15
RAD	01 00 0a
->RAD	01 00 62
RADIX,	01 00 0d
RADIX.	01 00 0c
RANDOM	01 00 2e
RMDR	01 00 51
RND	01 00 42
RPN	01 00 03
RTN	01 00 77
Rv	01 00 95
R^	01 00 96
SEED	01 00 30
SGN	01 00 4f
SIN	01 00 43
STOP	01 00 79
sx	01 00 23
sy	01 00 24
TAN	01 00 45
x!=0?	01 00 71
x<=0?	01 00 72
x<0?	01 00 73
x>0?	01 00 74
x>=0?	01 00 75
x=0?	01 00 76
x^2	01 00 3d
\x-	01 00 02
\x^	01 00 1b
XOR	01 00 a7
\x-w	01 00 22
x<>y	01 00 8f
x!=y?	01 00 6b
x<=y?	01 00 6c
x<y?	01 00 6d
x>y?	01 00 6e
x>=y?	01 00 6f
x=y?	01 00 70
xiy	01 00 14
x+yi	01 00 16
\y-	01 00 21
\y^	01 00 1c
y^x	01 00 56

Instructions with number argument

01 no oc

01: instruction
no: number 00..0Bh = 0..12
oc: opcode

Instruction	Hexcode
CF	01 no 91
ENG	01 no 12
FIX	01 no 10
FS?	01 no 92
SCI	01 no 11
SF	01 no 90

Instructions with an variable

01 va oc

01: instruction
va: variable 00..1Ah, 1Bh, 1Ch = A..Z, (I), (J)
oc: opcode

Instruction	Hexcode
LBL	01 va 7b *
INPUT	01 va 7c *
$FN_d	01 va 83
DSE	01 va 81
FN=	01 va 7f
ISG	01 va 80
RCL	01 va 89
RCL+	01 va 8a
RCL-	01 va 8b
RCL*	01 va 8c
RCL/	01 va 8d
SOLVE	01 va 82
STO	01 va 84
STO+	01 va 85
STO-	01 va 86
STO*	01 va 87
STO/	01 va 88
VIEW	01 va 7a
x<>	01 va 8e

* Valid range for va is only from 00 to 1Ah

Jump Commands

Instruction	Hexcode
GTO	90 lo hi
XEQ	91 lo hi

Command GTO

The jump command GTO has the hexcode 90 in the first byte. The two following bytes (little endian) contain the absolute jump address starting at 0001 for A001.

Example

Instruction	Hexcode
GTO A010	90 0a 00
GTO F001	90 a9 13

Command XEQ

The jump command XEQ has the hexcode 91 in the first byte. The two following bytes contain the absolute jump address.

91 lo hi

91: instruction
lo: low byte
hi: high byte

Example

Instruction	Hexcode
XEQ A001	91 01 00
XEQ B003	91 eb 03

Access to the Data Segment

Constants

The 41 constants are stored in a separate ROM segment.

80 co 00

80: instruction
co: constant 00..28h
00: zero byte (no opcode)

Instruction	Trigraph	Hexcode	Description
c	\016	80 00 00	Speed of light in vacuum
g	\^g	80 01 00	Standard acceleration of gravity
G	\018	80 02 00	Gravitation constant
Vm	\^V\^m	80 03 00	Molar volume of ideal gas
NA	\^N\015	80 04 00	Avogadro constant
Rb	\^R\oo	80 05 00	Rydberg constant
eV	\^e\^V	80 06 00	Elementary charge
me	\^m\^e	80 07 00	Electron mass
mp	\^m\^p	80 08 00	Proton mass
mn	\^m\^n	80 09 00	Neutron mass
mu	\^m\Gm	80 0a 00	Muon mass
k	\^k	80 0b 00	Boltzmann constant
h	\^h	80 0c 00	Planck constant
hbar	\023	80 0d 00	Planck constant over 2 pi
Ph0	\O/\021	80 0e 00	Magnetic flux quantum
a0	\^a\021	80 0f 00	Bohr radius
e0	\Ge\021	80 10 00	Electric constant
R	\020	80 11 00	Molar gas constant
F	\017	80 12 00	Faraday constant
u	\^u	80 13 00	Atomic mass constant
u0	\Gm\021	80 14 00	Magnetic constant
uB	\Gm\^B	80 15 00	Bohr magneton
uN	\Gm\^N	80 16 00	Nuclear magneton
up	\Gm\^p	80 17 00	Proton magnetic moment
ue	\Gm\^e	80 18 00	Electron magnetic moment
un	\Gm\^n	80 19 00	Neutron magnetic moment
uu	\Gm\Gm	80 1a 00	Muon magnetic moment
re	\^r\^e	80 1b 00	Classical electron radius
Z0	\^Z\021	80 1c 00	Characteristic impendence of vacuum
lc	\Gl\^c	80 1d 00	Compton wavelength
lcn	\Gl\^c\^n	80 1e 00	Neutron Compton wavelength
lcp	\Gl\^c\^p	80 1f 00	Proton Compton wavelength
a	\Ga	80 20 00	Fine structure constant
z	\157	80 21 00	Stefan–Boltzmann constant
t	\024	80 22 00	Celsius temperature
atm	\167\^t\^m	80 23 00	Standard atmosphere
gp	\Gg\^p	80 24 00	Proton gyromagnetic ratio
C1	\^C\^1	80 25 00	First radiation constant
C2	\^C\^2	80 26 00	Second radiation constant
G0	\^G\021	80 27 00	Conductance quantum
e	\^e	80 28 00	The base number of natural logarithm

Equation

The first valid entry has the offset 0776h.

81 lo hi

81: instruction
lo: low offset
hi: high offset

Instruction	Hexcode
EQN	81 lo hi

Expressions

The first valid entry has the offset 0776h.

83 lo hi

83: instruction
lo: low offset
hi: high offset

Instruction	Hexcode
expr	83 lo hi *
ALOG	83 lo hi
EXP	83 lo hi
IDIV	83 lo hi
INV	83 lo hi
REGT	83 lo hi
REGX	83 lo hi
REGY	83 lo hi
REGZ	83 lo hi
SQ	83 lo hi
SQRT	83 lo hi
XROOT	83 lo hi

*These include constants and numbers in mode ALG