Propeller Manual

3: Assembly Language Reference – TJZ
TJZ
Instruction: Test value and jump to address if zero.
TJZ Value, 〈#〉 Address
• Value (d-field) is the register to test.
•
Address (s-field) is the register or a 9-bit literal whose value is the address to jump to
when Value contains zero.
Opcode Table:
–INSTR– ZCRI –CON– –DEST– –SRC– Z Result C Result Result Clocks
111011 000i 1111 ddddddddd sssssssss
D = 0 0 Not Written 4 or 8
Concise Truth Table:
In Out
Destination Source Z C Effects Destination
1
Z C
$0000_0000; 0 $----_----; - - -
wr wz wc
$0000_0000; 0 1 0
$0000_0001; 1 $----_----; - - -
wr wz wc
$0000_0001; 1 0 0
1
Destination is not written unless the WR effect is given.
Explanation
TJZ tests the Value register and jumps to Address if it contains zero.
When the
WZ effect is specified, the Z flag is set (1) if the Value register contains zero.
TJZ requires a different amount of clock cycles depending on whether or not it has to jump. If
it must jump it takes 4 clock cycles, if no jump occurs it takes 8 clock cycles.
Propeller Manual v1.1 · Page 365