The new 7903 MPU provides a plug-in upgrade for systems currently using the 6502 microprocessor. The 7903 is fully pin-compatible and software upward-compatible with the 6502. Additionally, many of the formerly unused opcodes are used to provide an enhanced instruction set providing features normally found only on much larger systems. The new instructions are listed below.
BBI |
Branch in Blinking Indicator |
BH |
Branch and Hang |
BCBF |
Branch on Chip Box Full |
BPO |
Branch on Power Off |
BSO |
Branch on Sleepy Operator |
IIB |
Ignore Inquiry and Branch |
RPB |
Reverse Parity and Branch |
BCH |
Branch on CPU Halted |
BTAD |
Branch To Auto Destruct |
JRL |
Jump to Random Location |
JSP |
Jump on Sexy Programmer |
FAG |
Fold And Go |
AI |
Add Improper |
DO |
Divide and Overflow |
DC |
Divide and Conquer |
SRZ |
Subtract and Reset to Zero |
ARZ |
Add and Reset to Zero |
XM |
Exclusive Maybe |
PAII |
Prevent All Interrupts and Interrupt |
PI |
Punch Invalid |
RI |
Read Invalid |
RCSD |
Read Card and Scramble Data |
RCR |
Rewind Card Reader |
RASC |
Read And Shred Card |
BCR |
Backspace Card Reader |
BCP |
Backspace Card Punch |
RCI |
Read Card and Ignore |
RCS |
Read Card Sideways |
SSJ |
Select Stacker and Jam |
RP |
Read Printer |
FSRA |
Forms Skip and Run Away |
BSP |
BackSpace Printer |
PBC |
Print and Break Chain |
TDB |
Transfer and Drop Bits |
MDB |
Move and Drop Bits |
MLR |
Move and Lose Record |
MWC |
Move and Wrap Core |
MC |
Move Continuous |
CM |
Circulate Memory |
WWLR |
Write Wrong Length Record |
RNR |
Read Noise Record |
RIRG |
Read Inter Record Gap |
REOF |
Read End Of File |
BST |
Backspace and Stretch Tape |
RBT |
Rewind and Break Tape |
MTI |
Make Tape Invalid |
PMT |
Punch Magnetic Tape |
PDT |
Punch and Delete Tape |
MET |
Misread and Eat Tape |
PTAB |
Position Tape Ass-Backwards |
STT |
Stretch and Tangle Tape |
ST |
Stretch Tape |
SRSD |
Seek Record and Scar Disk |
RD |
Rewind Disk |
BD |
Backspace Disk |
ED |
Eject Disk |
TD |
Throw Disk |
LCD |
Launch Cartridge Disk |
FD |
Flip Disk |
DF |
Disk Feed |
UER |
Update and Erase Record |
CVU |
ConVert to Unary |
CVS |
ConVert to Sesquinary |
CRN |
Convert to Roman Numerals |
WRTC |
Wind Real-Time Clock |
WWTC |
Wind Wrong-Time Clock |
PCB |
Pause for Coffee Break |
SPD |
Start and Power Down |
PDN |
Power Down and Normalize |
EBQR |
Enable Bi-Quinary Arithmetik |
LCC |
Load and Clear Core |
EROS |
Erase Read-Only Store |
RWOM |
Read Write-Only Memory |
WROM |
Write Read-Only Memory |
FCE |
Fill Core with Epoxy |
DMPK |
Destroy Memory Protect Key |
UC |
Unwind Core |
BPP |
Blob Plotter Pen |
MPS |
Move Pen Somewhere |
DPMD |
Drop Pen and Mangle Drum |
APX |
Apply Power and Explode |
HCF |
Halt and Catch Fire |
CCP |
Clear Core and Proceed |
CCCP |
Conditionally Clear Core and Proceed |
EIOC |
Execute Invalid Op Code |
EPI |
Execute Programmer Immediate |
SPSW |
Scramble Program Status Word |
ERAF |
Execute Relocatable Address Field |
EPSW |
Execute Program Status Word |
EM |
EMulate 407 |
SSN |
Set Serial Number |
STI |
STore Immediate |
PSP |
Push Stack Pointer |
- American Gumby Corporation, 1009 Mercaptan Road, Epstein-Barr, NJ 11235
- See also: Signetics 25120 Random Access write/only Memory