Nicron #16 17 января 1997

Железо

Iron - an overview of the microprocessor Zilog Z380, continued.

                          MPU Z380

[Continued. Previous publications - in numbers 15,14,12,11,10,
9,8,7]

(C) WLODEK BLACK

        Command group transitions

Mnemonic Meaning Commentary

New commands:

JR ee PC <- PC + ee +4 relative shift of two byte offset, 
counting emomu of instruction code that follows the JR         
(4 bytes) 

JR cc, ee same - go for the condition C, NC, Z, NZ

JR eee PC <- PC + eee +5 on the transition to 3-by tovomu 
shift, measured         of the next instruction (5 bytes)


JR cc, eee same - go for the condition C, NC, Z, NZ

DJNZ ee B <- B-1;
        If B is not 0, then PC <- PC + ee +4
        Otherwise - PC <- PC +4

                Operator cycle register B
        with respect to the transition to a 2-byte shift Niya 
on the following instructions (4 bytes) 

DJNZ eee B <- B-1;
        If B is not 0, then PC <- PC + eee +5
        Else PC <- PC +5

                Same with the transition to a 3-byte offset th


        Group of commands to access routines
        and return from subroutines

New commands:

CALR e (SP-1) <- PCh Go to the subprogramme include (SP-2) <- 
PCl with respect to the next team         SP <- SP-2 Offset e

        PC <- PC + e +3

CALR cc, e The same condition on Z, NZ, C, NC, S, NS, NV, V,
        PE, PO, P, M

CALR ee (SP-1) <- PCh Go to the subprogramme include (SP-2) <- 
PCl with respect to the next team         SP <- SP-2 2-byte 
offset ee         PC <- PC + ee +4


CALR cc, ee Same as on the conditions for CALR cc, e

CALR eee (SP-1) <- PCh Go to the subprogramme include (SP-2) <- 
PCl with respect to the next team         SP <- SP-2 3-byte 
offset eee         PC <- PC + eee +5


CALR cc, eee Same as on the conditions for CALR cc, e

In Advanced mode, the CPU is stored in a stack of 4-byte
return address, respectively, the stack grows by 4 values.
When using the "old" RST commands in advanced mode
the missing bits to 32 bits are complemented with zeros.
If you are using a non-dilated relative addressing mode of the 
processor address is calculated modulo 65536; older 16-bit = 0. 
In all cases, e, ee, eee - MSB is the sign. 

P.S. Amendment:
In the 15 th issue has crept typo. Published by:
DIVUV [HL,] pp.
Needed:
DIVUW [HL,] pp.
I express my apologies to readers!

[To be continued].