em6522 EM Microelectronic, em6522 Datasheet - Page 25

• Manufacturer Part Number: em6522
• Description: Mfp Version Of Em6622 Ultra Low Power Microcontroller With 4x32 Lcd Driver
• Manufacturer: EM Microelectronic

Figure 18. Sample Basic Serial Port Connections
6.6.7 Reset and Sleep on Port SP
During circuit initialization, all option registers are reset by Power On Reset and therefore all pull-ups are off
and all pull-downs are on. During Sleep mode, Port SP inputs are cut-off , the circuit is in Reset State. However
the Reset State does not reset the option registers and pull-downs, if previously turned on, remain on even
during Sleep mode. After any reset the serial interface parameters are reset to : Slave mode, Start and Status
= 0, LSB first, negative edge shift , PSP[3:0] tristate.
Note : A write operation in the control registers or in the data registers while Start is high will change internal
values and may cause an error condition. The user must take care of the serial interface status before writing
internal registers. In order to read the correct values on the data registers, the shift operation must be halted
during the read accesses.
Copyright © 2005, EM Microelectronic-Marin SA
Figure 17 Shift Operation and IRQ Generation
SCLK = System Clock;
Shift
Register
Shift Ck
Start
IRQ
SIN
OM[1]=0, OM[0]=1 : Re-Synchronized on positive SCLK clock edge data out
SOUT
OM[1]=1, OM[0]=0 : direct data out on pos. or neg. SCLK clock edge depending on bit POSnNeg
SOUT
Clock Source
SP[3]; SCLKOut
SP[2]; SOUT
SP[0]; SIN
Ready
SP[1]: Status
EM 6522
R
10010011
1
Master Mode
0
1
Active Edge = Neg. Edge;
0
1
0
Serial Clock In
Serial Data In
Serial Data Out
Status Output
CS
External
0
0
0
1
Sense = MSB First
optional connection
0
1
0
25
SP[3]; SCLKIn
SP[2]; SOUT
SP[0]; SIN
SP[1]; Status
EM 6522
1
0
0
1
0
Slave Mode
1
0
1
1
www.emmicroelectronic.com
Ready
Serial Clock Out
Serial Data In
Serial Data Out
EM6522
External
0
1
01001100