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Instruction NameBranch on External
CP1610 Clock Cycles7 or 9
Opcode Range$0210-$21F, $0230-$23F

The Branch on External opcode (BEXT) is a two-decle opcode that is a part of the Branch family of opcodes. This instruction causes the CP1610 to branch if the external pins EBCA0-EBCA3 match the specified value. If this condition is true, the CP1610 branches to the address specified by the following parameters.

   Format - Decle #1    Format - Word #2 (All 16 bits are significant)
   0000:0010:00d1:cccc  aaaa:aaaa:aaaa:aaaa
d indicates the direction of the branch such that: d == 0 indicates to branch in the forward direction d == 1 indicates to branch in the reverse direction
cccc The value to assert on external pins EBCA0-EBCA3. The input EBCI determines whether the branch gets taken.
aaaaaaaaaaaaaaaa indicates the amount of offset

See the Branch opcode family documentation for more information.