WRWORD
Instruction: Write a word to main memory.
WRWORD Value, < # > Address
- Value (d-field) is the register containing the 16-bit value to write to main memory.
- Address (s-field) is a register or a 9-bit literal whose value is the main memory address to write to.
Opcode Table:
–INSTR– ZCRI –CON– –DEST– –SRC– | Z Result | C Result | Result | Clocks |
000001 000i 1111 ddddddddd sssssssss | — | — | Not Written | 8..23 |
Concise Truth Table:
In | Out | ||||||
Destination | Source | Z | C | Effects | Destination1 | Z2 | C |
$----_----; - | $----_----; - | - | - | wz wc | n/a | 1 | 0 |
1 Destination Out doesn't exist since including a WR effect would turn WRWORD into a RDWORD instruction.
2 The Z flag is set (1) unless the main memory address (bits 13:1) is on a long boundary.
Explanation
WRWORD synchronizes to the Hub and writes the lowest word in Value to main memory at Address.
The WR effect can not be used with WRWORD as that would change it to a RDWORD instruction.
WRWORD is a hub instruction. Hub instructions require 8 to 23 clock cycles to execute depending on the relation between the cog's hub access window and the instruction's moment of execution. See Hub for more information.
Unless otherwise noted, content on this site is licensed under the
Creative Commons Attribution-ShareAlike 4.0 International License.
