MAX1463 Datasheet, PDF (27/49 Pages) Maxim Integrated Products – Low-Power Two-Channel Sensor Signal Processor

Low-Power Two-Channel Sensor
Signal Processor
BNX
Branch If Not Zero
Op-code:
1100 XXXX_BINARY CXh
Operation:
If I-register ≠ 0000h then:
PC-register ← PC-register + X-register
Else:
PC-register ← PC-register + 1 (point to
next instruction)
CPU Cycles required:
1 cycle
Description:
Perform a 16-bit check of the I-register for a nonzero
condition and, if true, add the contents of the X-register
to the program pointer register. This causes an immedi-
ate jump to the new program memory location. The
next instruction to execute is fetched from the program
memory byte pointed to by the new contents of the PC-
register.
A 1_B in any bit of the I-register is indicative of a nonzero
number to which the test for a zero value fails. This
causes the “else” operation to be performed and the
PC-register is incremented by one pointing to the next
sequential instruction in program memory to be execut-
ed. The effect bypasses the branch mechanism and
normal, sequential, code execution results.
The next instruction to execute is fetched from the pro-
gram memory byte pointed to by the new contents of
the PC-register.
The previous contents of PC-register are overwritten
and lost.
Two’s complement data format is preserved.
Branching may occur.
No other registers are affected.
RDX
Read Port X
Op-code:
1101XXXX_BINARY DXh
Operation:
A-register ← port-X
PC-register ← PC + 1 (point to next instruction)
CPU Cycles required:
1 cycle
Description:
Perform a 16-bit move operation from port-X to the A-
register.
The port-X contents are unchanged.
The previous contents of A-register are overwritten
and lost.
The port-X can be any of the CPU ports.
PC is incremented once to point to the next instruction
in program memory.
Two’s complement data format is preserved.
No branching occurs.
No other registers are affected.
WRX
Write Port X
Op-code:
1110 XXXX_BINARY EXh
Operation:
Port-X ← A-register
PC-register ← PC + 1 (point to next instruction)
CPU Cycles required:
1 cycle
Description:
Perform a 16-bit move operation from the A-register to
port-X.
The A-register contents are unchanged.
The previous contents of port-X are overwritten
and lost.
The port-X can be any of the CPU ports.
PC is incremented once to point to the next instruction
in program memory.
Two’s complement data format is preserved.
No branching occurs.
No other registers are affected.
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