Product manual
4HIS BLOCK IS IDENTIlED BY DATA hv IE &%H
"YTES n 53%2 $!4! s
,AST BYTES BYTE AND BYTE #2# s
3.17 Card Reset State
!FTER POWERUP THE 3$ CARD IS IN THE )DLE 3TATE 3ENDING COMMAND #-$ ALSO PUTS THE CARD
IN THE )DLE 3TATE !T LEAST CLOCK CYCLES SHOULD BE SENT TO THE CARD WITH THE $ATA /UT AND #3
LINES SET TO LOGIC hv BEFORE STARTING TO COMMUNICATE WITH THE CARD
4HE 3$ CARD IS INITIALLY IN THE 3$ "US MODE )T WILL ENTER THE 30) MODE IF THE #3 LINE IS HELD
LOW WHILE SENDING THE #-$ COMMAND 7HEN THE CARD SWITCHES TO THE 30) MODE IT WILL
RESPOND WITH THE 30) MODE 2 RESPONSE FORMAT )N 30) MODE #2# CHECKING IS DISABLED BY
DEFAULT (OWEVER BECAUSE THE CARD POWERSUP IN THE 3$ "US MODE #-$ COMMAND MUST
BE SENT WITH A VALID #2# BYTE BEFORE THE CARD IS PUT INTO 30) MODE 7HEN SENDING THE #-$
COMMAND THE #2# BYTE IS lXED AND IS EQUAL TO H 4HE FOLLOWING HEXADECIMAL BYTE
COMMAND SEQUENCE CAN THEN BE USED TO SEND THE #-$ COMMAND AFTER A POWERUP SEE
4ABLE WITH THE COMMAND lELD SET TO hv FOR #-$
4HE STEPS TO SWITCH THE 3$ CARD INTO 30) MODE SHOULD THEREFORE BE AS FOLLOWS
0OWERUP s
3END AT LEAST CLOCK PULSES TO THE CARD WITH #3 AND $ATA /UT LINES SET TO LOGIC hv s
3ET #$ LINE LOW s
3END BYTE #-$ COMMAND h v TO PUT THE CARD IN 30) MODE s
#HECK 2 RESPONSE TO MAKE SURE THERE ARE NO ERROR BITS SET s
3END COMMAND #-$ REPEATEDLY UNTIL THE hINIDLESTATEv BIT IN 2 RESPONSE IS SET TO hv s
AND THERE ARE NO ERROR BITS SET
4HE CARD IS NOW READY FOR READWRITE OPERATIONS s
$URING THE RESET STATE THE CARD CLOCK FREQUENCY SHOULD BE BETWEEN n +(Z !FTER THE RESET
STATE THE MAXIMUM CLOCK FREQUENCY CAN BE INCREASED TO -(Z -(Z FOR THE --#
3.18 Summary
4HE BRIEF DETAILS OF COMMONLY USED MEMORY CARDS ARE GIVEN IN THIS CHAPTER 3$ CARDS ARE
CURRENTLY THE MOST WIDELY USED MEMORY CARDS 4HE TECHNICAL DETAILS AND COMMUNICATION
METHODS OF THESE CARDS HAVE BEEN DESCRIBED IN DETAIL IN THE CHAPTER
Memory Card 135
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