Epson CMOS 32-Bit Single Chip Microcomputer S1C33L03 Technical Manual page 530

VI SDRAM CONTROLLER BLOCK: SDRAM INTERFACE
;;; SDRAM auto refresh count high-order register
xld.w %r0,0x39FFC7
xld.w %r1,0x00
ld.b [%r0],%r1
;///////////////////////////////////////////
;;; SDRAM self refresh count register
;;; xld.w %r0,0x39FFC8
;;; xld.w %r1,0x0f
;;; ld.b [%r0],%r1
;///////////////////////////////////////////
;;; SDRAM advanced control register
xld.w %r0,0x39FFC9
xld.w %r1,0x20
ld.b [%r0],%r1
;;;*****************************************************************
;;;***************** SDRAM controller power up *********************
;;;*****************************************************************
xld.w %r0,0x39FFC1
xld.w %r1,0x39FFCA
xld.w %r2,0x0
xld.w %r3,0x10
;;; enable SDRAM signal
bset [%r0],0x7
SDRAM_SIGNAL_EN:
add %r2,0x1
cmp %r2,%r3
jrne SDRAM_SIGNAL_EN
;;; SDRAM power up
bset [%r0],0x6
POWER_UP:
btst [%r1],0x7
jrne POWER_UP
;;;------------------------ end of SDRAM access configuration ---------------------------
ret
The SDRAM can be accessed after executing the above program.
Example of initialization routine for 4M words
When using a 32MB SDRAM, modify two parts of the above program example indicated with (note 1) and (note
2) as follows:
(note 1)
;///////////////////////////////////////////
;;; SDRAM area configuration register
xld.w %r0,0x39FFC0
xld.w %r1,0xc8
ld.b [%r0],%r1
;///////////////////////////////////////////
(note 2)
;///////////////////////////////////////////
;;; SDRAM address configuration register
xld.w %r0,0x39FFC2
xld.w %r1,0x2a
ld.b [%r0],%r1
;///////////////////////////////////////////
B-VI-2-34
;
;
;
;
;
;
;
; data width -> 16bit, bank interleave -> on
;
; SDRAM control register
; SDRAM status register
; set SDRENA[D7/0x39FFC1]
; SDRAM signal enable waiting loop
; set SDRINI[D6/0x39FFC1]
; SDRAM power-up waiting loop
16 bits 4 banks (32MB) of SDRAM
;
; set area13&14 to SDRAM area, #SDCE0(#CE13) available
; (32MB area available)
;
; col 512 / row 8K / bank 4 -> 256Mb[32MB] available
;
EPSON
S1C33L03 FUNCTION PART