Epson CMOS 32-Bit Single Chip Microcomputer S1C33L03 Uživatelský manuál stáhnout pdf (Strana 96)

7 DETAILS OF INSTRUCTIONS

EPSON

S1C33 FAMILY C33 PE CORE MANUAL

jrne sign8 / jrne.d sign8

Function

Conditional PC relative jump

Standard) pc

← pc + sign8 × 2 if !Z is true

Extension 1) pc

← pc + sign22 if !Z is true

Extension 2) pc

← pc + sign32 if !Z is true

Code

15 12 11 8 7 0

0 0 0 1 1 0 1 d

sign8

0x1A__, 0x1B__

jrne sign8 when d bit (bit 8) = 0

jrne.d sign8 when d bit (bit 8) = 1

Flag

IE C V Z N

– – – – –

Mode

Signed PC relative

CLK

jrne Two cycles (when not branched), Three cycles (when branched)

jrne.d Two cycles

Description

(1) Standard

jrne

sign8 ; = "jrne sign9", sign8 = sign9(8:1), sign9(0)=0

If the condition below has been met, this instruction doubles the signed 8-bit immediate

sign8

and adds it to the PC for branching the program flow to the address. It does not branch if the

condition has not been met.

• Z flag = 0 (e.g. “A

≠ B” has resulted by cmp A,B)

The

sign8 specifies a halfword address in 16-bit units.

The

sign8 (×2) allows branches within the range of PC - 0x100 to PC + 0xFE.

(2) Extension 1

ext

imm13 ; = sign22(21:9)

jrne

sign8 ; = "jrne sign22", sign8 = sign22(8:1), sign22(0)=0

The ext instruction extends the displacement to be added to the PC into signed 22 bits using its

13-bit immediate data

imm13. The sign22 allows branches within the range of PC - 0x200000

to PC + 0x1FFFFE.

(3) Extension 2

ext

imm13 ; imm13(12:3)= sign32(31:22)

ext

imm13 ; = sign32(21:9)

jrne

sign8 ; = "jrne sign32", sign8 = sign32(8:1), sign32(0)=0

The

ext instructions extend the displacement to be added to the PC into signed 32 bits using

their 13-bit immediates (

imm13 × 2). The displacement covers the entire address space. Note

that the low-order 3 bits of the first

imm13 are ignored.

(4) Delayed branch (d bit = 1)

jrne.d sign8

For the jrne.d instruction, the next instruction becomes a delayed instruction. A delayed

instruction is executed before the program branches. Exceptions are masked in intervals

between the jrne.d instruction and the next instruction, so no interrupts or exceptions occur.

Example

cmp %r0,%r1

jrne 0x2 ; Skips the next instruction if r0

≠ r1.

Caution

When the jrne.d instruction (delayed branch) is used, be careful to ensure that the next

instruction is limited to those that can be used as a delayed instruction. If any other instruction

is executed, the program may operate indeterminately. For the usable instructions, refer to the

instruction list in the Appendix.

1 2 ... 91 92 93 94 95 96 97 98 99 100 101 ... 180 181

Komentáře k této Příručce

Žádné komentáře

Epson CMOS 32-Bit Single Chip Microcomputer S1C33L03 Uživatelský manuál Strana 96

Komentáře k této Příručce

Související produkty a manuály pro Barebones pro PC / pracovní stanice Epson CMOS 32-Bit Single Chip Microcomputer S1C33L03