45111 Datasheet, PDF (157/184 Pages) List of Unclassifed Manufacturers – 14-DAY MONEY BACK GUARANTEE

15 Appendix E: SX Data Sheet
General-purpose registers can only be accessed within one bank at a time. The general-purpose registers
are numbered $10 through $1F. The active bank is controlled by the upper 3 bits of the FSR (SX20/28) as
shown in Figure 26 – SX20/28 General Purpose Register Addressing (direct) or the upper 4 bits of the
FSR (SX48/52) as shown in Figure 27 – SX 48/52 General-Purpose Register Addressing (direct).
Figure 26 - SX20/28 General Purpose Register Addressing (direct)
fr (5-bit address in instruction)
4
3
2
1
0
=1
Register Selection Bits
$10 - $1F
$00, $20, $40, $60, $80,
$A0, $C0, or $E0
7
6
5
Bank Selection Bits
FSR ($04)
4
3
2
1
0
Ignored because fr.4 is 1
$00-
$01-
$02-
Global
IND
RTCC
PC
$0F- $0F
Bank 0 Bank 1 Bank 2
Bank 7
$10- $0
$0
$0
$0
$11- $1
$1
$1
———
$1
$12- $2
$2
$2
$2
—
—
$1F- $F
$F
$F
$F
SX-Key/Blitz Development System Manual 2.0 • Parallax, Inc. • Page 157