1
0
mirror of https://github.com/hsoft/collapseos.git synced 2024-12-25 04:58:05 +11:00

drv/sdc: implement core words in z80

In addition to making the driver significantly faster, it allows us
to make SDC port configuration opaque to sdc.fs.
This commit is contained in:
Virgil Dupras 2020-04-18 20:33:51 -04:00
parent a70366aa43
commit a2d89de557
4 changed files with 42 additions and 28 deletions

View File

@ -1,12 +1,3 @@
: SDC_CSHIGH 6 ;
: SDC_CSLOW 5 ;
: SDC_SPI 4 ;
: _sdcSR SDC_SPI PC! SDC_SPI PC@ ;
: _sel 0 SDC_CSLOW PC! ;
: _desel 0 SDC_CSHIGH PC! ;
( -- n )
: _idle 0xff _sdcSR ;
@ -93,30 +84,31 @@
( cmd arg1 arg2 -- r )
( Send a command that expects a R1 response, handling CS. )
: SDCMDR1 _sel _cmd _desel ;
: SDCMDR1 _sdcSel _cmd _sdcDesel ;
( cmd arg1 arg2 -- r arg1 arg2 )
( Send a command that expects a R7 response, handling CS. A R7
is a R1 followed by 4 bytes. arg1 contains bytes 0:1, arg2
has 2:3 )
: SDCMDR7
_sel
_sdcSel
_cmd ( r )
_idle 256 * ( r h )
_idle + ( r arg1 )
_idle 256 * ( r arg1 h )
_idle + ( r arg1 arg2 )
_desel
_sdcDesel
;
: _err _sdcDesel ABORT" SDerr" ;
( Initialize a SD card. This should be called at least 1ms
after the powering up of the card. r is result.
Zero means success, non-zero means error. )
after the powering up of the card. )
: SDC$
( Wake the SD card up. After power up, a SD card has to
receive at least 74 dummy clocks with CS and DI high. We
send 80. )
10 0 DO 0xff SDC_SPI PC! LOOP
10 0 DO _idle DROP LOOP
( call cmd0 and expect a 0x01 response (card idle)
this should be called multiple times. we're actually
@ -128,16 +120,16 @@
SDCMDR1
DUP 0x01 = IF LEAVE THEN
LOOP
0x01 = NOT IF 1 EXIT THEN
0x01 = NOT IF _err THEN
( Then comes the CMD8. We send it with a 0x01aa argument
and expect a 0x01aa argument back, along with a 0x01 R1
response. )
0b01001000 0 0x1aa ( CMD8 )
SDCMDR7 ( r arg1 arg2 )
0x1aa = NOT IF 2 EXIT THEN ( arg2 check )
0 = NOT IF 3 EXIT THEN ( arg1 check )
0x01 = NOT IF 4 EXIT THEN ( r check )
0x1aa = NOT IF _err THEN ( arg2 check )
0 = NOT IF _err THEN ( arg1 check )
0x01 = NOT IF _err THEN ( r check )
( Now we need to repeatedly run CMD55+CMD41 (0x40000000)
until the card goes out of idle mode, that is, when
@ -147,20 +139,17 @@
BEGIN
0b01110111 0 0 ( CMD55 )
SDCMDR1
0x01 = NOT IF 5 EXIT THEN
0x01 = NOT IF _err THEN
0b01101001 0x4000 0x0000 ( CMD41 )
SDCMDR1
DUP 0x01 > IF DROP 6 EXIT THEN
DUP 0x01 > IF _err THEN
NOT UNTIL
( Out of idle mode! Success! )
0
;
: _err _desel ABORT" SDerr" ;
( dstaddr blkno -- )
: _sdc@
_sel
_sdcSel
0x51 ( CMD17 )
0 ROT ( a cmd 0 blkno )
_cmd
@ -181,7 +170,7 @@
_idle 256 *
_idle + ( crc2 )
_wait DROP
_desel
_sdcDesel
= NOT IF _err THEN
;
@ -194,7 +183,7 @@
( srcaddr blkno -- )
: _sdc!
_sel
_sdcSel
0x58 ( CMD24 )
0 ROT ( a cmd 0 blkno )
_cmd
@ -215,7 +204,7 @@
_sdcSR DROP ( lsb )
_sdcSR DROP
_wait DROP
_desel
_sdcDesel
;
: SDC!

21
drv/sdc.z80 Normal file
View File

@ -0,0 +1,21 @@
( n -- n )
( Initiate SPI exchange with the SD card. n is the data to
send. )
CODE _sdcSR
HL POPqq,
chkPS,
A L LDrr,
SDC_SPI OUTnA,
NOP, NOP,
SDC_SPI INAn,
L A LDrr,
HL PUSHqq,
;CODE
CODE _sdcSel
SDC_CSLOW OUTnA,
;CODE
CODE _sdcDesel
SDC_CSHIGH OUTnA,
;CODE

View File

@ -10,6 +10,7 @@ BOOTSRCS = conf.fs \
$(FDIR)/boot.fs \
$(FDIR)/z80c.fs \
$(BASEDIR)/drv/acia.z80 \
$(BASEDIR)/drv/sdc.z80 \
$(FDIR)/icore.fs \
$(EDIR)/xstop.fs

View File

@ -2,5 +2,8 @@
0xf000 CONSTANT RS_ADDR
0x80 CONSTANT ACIA_CTL
0x81 CONSTANT ACIA_IO
4 CONSTANT SDC_SPI
5 CONSTANT SDC_CSLOW
6 CONSTANT SDC_CSHIGH
RAMSTART 0x70 + CONSTANT ACIA_MEM