Radio Shack TRS-80 Quick Reference Manual page 22

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BVC
Branch on Over1low Clear.
Tests the stale ofthe V (over1low) bit and causes a branch if il is
clear. When used after an operation on twos complement binary
values, this instruction will branch if Ihere was no overllow.
41
BOB
Branch to Subroutine.
The pr09ram counter is pushed onto the stack. The program
counterls then loaded with the sum of Ihe program counter and
the offset.
BVO
Branch on Overllow Sel.
Tests Ihe state of the V (overllow) bit and causes a branch if it is
sel. When used aller an operation on twoscomplement binary
values, this instruction will branch if Ihere was an overllow.
BRA
Branch Always.
Causes an unconditional bran<:h.
BHN
Branch Never.
Does not cause a branch. This instruction is essentially a no
operation, bul has a bit pattern logically related to Branch
Always.
BLT
Branch on Less Than Zero.
Causes a branch il either, but not both, of the N (negative) or V
(overflow) bits are sel. When used alter a subtract or compare
operation on twos complement binary values, this instruction will
branch if the register was less than the memory operand.
BPL
Branch on Plus.
Tests the state of the N (negative) bit and causes a branch if it is
clear.
BNE
Branch not Equal.
Tests the state of the Z (zero) bit and causes a branch if it is clear.
When used aller a subtractorcompare operation on any binary
values,this instruction will branch iflhe register is, orwould ba,
not equalto the memory operand.
Branch on Minus.
Tests the state of the N (negative) bit and causes a branch if set.
BMI
BLS
Branch on Loweror Same.
Causes a branch if the previous operation caused either a carry
or a zero resull. When used after a subtract or compare
operation on unsigned binaryvalues, this instruction will branch
if the register was lower than or the same as the memory
operand.
BHO
Branch if Higheror Same.
Tests thestate of the C (carry) bit and causes a branch if it is
c1ear. When used alter asubtractorcompareon
unsi~ned
binary
values, this instruction will branch if the registerwas hlgherthan
or the same as the memory operand.
BGT
BHI
Branch if Higher.
Causes a branch if the previous operation caused neither a carry
nor a zero result. When used after asubtract or compare
operation on unsigned binaryvalues, this instruction will branch
if the registerwas higherthan the memory operand.
Branch on Greater.
Causes a branch
if
the N (negative) bit and V (overllow) bilara
either bath selor both clear and the Z (zero) bit is clear, When
used alter a subtract or compare operation on twos complement
values, this instruction will branch ilthe registerwas greaterthan
the memOlY operand.
BGE
Branch on Greater Than or Equal
talera.
Causes a branch if the N (negalive) bit and the V (overflow) bit
are either bath setor both clear. When used affer a sublract or
compare operation on twas complement values, Ihis instruction
will branch if the registerwas grea/er than araqual to the memory
operand.
BLO
Branch on Lower.
Tests the state of the C (carry) bit and causes a branch if it is set.
When used alter a subtract or compare on unsigned binary
values, this instruction will branch if the registerwas lower than
the memoryoperand.
BEQ
Branch if Equal.
Tests the slateal the Z (zero) bit and causes a branch
if il
is set.
When used alter asublracl orcompare operation, this instruction
will branch
if
the compared values, signed or unsigned, were
exacllythe same.
40
BLE
Branch on Less Than or Equalto Zero.
Causes a branch if the exclusive OR of the N (negative) and V
(over1low) bits is 1 or if the Z (zero) bit is sel. When used alter a
subtract or compare operation on twos complement values, this
instruction will branch il the registerwas less than or equal tothe
memoryoperand.
BIT
Bit Test.
Per10rms a logical AN D of the contents of accumulator A or Band
the contents of a memory location and modifies the condition
codes accordingly. The contents of accumulator A or B and the
memory location are not affeeted.