Renesas rl78 User Manual
RL78/G1A
CHAPTER 12 SERIAL ARRAY UNIT
R01UH0305EJ0200 Rev.2.00
421
Jul 04, 2013
12.3.8 Serial channel start register m (SSm)
The SSm register is a trigger register that is used to enable starting communication/count by each channel.
When 1 is written a bit of this register (SSmn), the corresponding bit (SEmn) of serial channel enable status register m
(SEm) is set to 1 (Operation is enabled). Because the SSmn bit is a trigger bit, it is cleared immediately when SEmn = 1.
The SSm register can be set by a 16-bit memory manipulation instruction.
The lower 8 bits of the SSm register can be set with an 1-bit or 8-bit memory manipulation instruction with SSmL.
Reset signal generation clears the SSm register to 0000H.
Figure 12-11. Format of Serial Channel Start Register m (SSm)
Address: F0122H, F0123H (SS0) After reset: 0000H R/W
Symbol 15
14
13
12
11
10
9 8 7 6 5 4 3 2 1 0
SS0
0 0 0 0 0 0 0 0 0 0 0 0
SS03
SS02
SS01 SS00
Address: F0162H, F0163H (SS1)
Note 1
After reset: 0000H R/W
Symbol 15
14
13
12
11
10
9 8 7 6 5 4 3 2 1 0
SS1
0 0 0 0 0 0 0 0 0 0 0 0 0 0
SS11 SS10
SSmn
Operation start trigger of channel n
0
No trigger operation
1
Sets the SEmn bit to 1 and enters the communication wait status
Note 2
.
Notes 1. 32, 48, 64-pin products only
2.
If set the SSmn = 1 to during a communication operation, will wait status to stop the communication.
At this time, holding status value of control register and shift register, SCKmn and SOmn pins, and
FEFmn, PEFmn, OVFmn flags.
Cautions 1. Be sure to clear bits 15 to 4 of the SS0 register and bits 15 to 2 of the SS1 register to “0”.
2. For the UART reception, set the RXEmn bit of SCRmn register to 1, and then be sure to set
SSmn to 1 after 4 or more f
MCK
clocks have elapsed.
Remarks 1. m: Unit number (m = 0, 1), n: Channel number (n = 0 to 3)
2. When the SSm register is read, 0000H is always read.