Difference between revisions of "BEXT"
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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.<br/> | 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.<br/> | ||
| − | Format - Decle #1 Format - Word #2 ( | + | Format - Decle #1 Format - Word #2 (All 16 bits are significant) |
0000:0010:00d1:cccc aaaa:aaaa:aaaa:aaaa<br/> | 0000:0010:00d1:cccc aaaa:aaaa:aaaa:aaaa<br/> | ||
where:<br/> | where:<br/> | ||
| Line 17: | Line 17: | ||
d == 0 indicates to branch in the forward direction | d == 0 indicates to branch in the forward direction | ||
d == 1 indicates to branch in the reverse direction<br/> | d == 1 indicates to branch in the reverse direction<br/> | ||
| − | cccc | + | cccc The value to assert on external pins EBCA0-EBCA3. |
| + | The input EBCI determines whether the branch gets taken.<br/> | ||
aaaaaaaaaaaaaaaa indicates the amount of offset | aaaaaaaaaaaaaaaa indicates the amount of offset | ||
See the [[Branch]] opcode family documentation for more information. | See the [[Branch]] opcode family documentation for more information. | ||
Revision as of 18:53, 12 January 2005
| Instruction Name | Branch on External |
| Mnemonics | BEXT |
| CP1610 Clock Cycles | 7 or 9 |
| Interruptible | Yes |
| 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
where:
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.
