
22 Remote Controller (REMC)
S1C17003 TECHNICAL MANUAL
EPSON
22-3
22.3 Carrier Generation
The REMC module incorporates a carrier generation circuit that generates a carrier signal for transmission in
accordance with the clock set by the software and carrier H and L section lengths.
The prescaler output clock is used for the carrier signal generation clock. The prescaler generates 15 different
clocks, dividing the PCLK clock from 1/1 to 1/16K. One is selected by CGCLK[3:0] (D[15:12]/REMC_PSC
register).
CGCLK[3:0]: Carrier Generator Clock Select Bits in the REMC Prescaler Clock Select (REMC_PSC) Register
(D[15:12]/0x5340)
Table 22.3.1: Carrier generation clock selection
CGCLK[3:0]
Prescaler output clock
CGCLK[3:0]
Prescaler output clock
0xf
Reserved
0x7
PCLK-1/128
0xe
PCLK-1/16384
0x6
PCLK-1/64
0xd
PCLK-1/8192
0x5
PCLK-1/32
0xc
PCLK-1/4096
0x4
PCLK-1/16
0xb
PCLK-1/2048
0x3
PCLK-1/8
0xa
PCLK-1/1024
0x2
PCLK-1/4
0x9
PCLK-1/512
0x1
PCLK-1/2
0x8
PCLK-1/256
0x0
PCLK-1/1
(Default: 0x0)
For more information on prescaler control, refer to “9 Prescaler (PSC).”
Note: The prescaler must run before the REMC module.
The carrier H and L section lengths are set by REMCH[5:0] (D[5:0]/REMC_CARH register) and REMCL[5:0]
(D[13:8]/REMC_CARL register), respectively. These registers set a value corresponding to the number of clock
cycles selected above + 1.
REMCH[5:0]: H Carrier Length Setup Bits in the REMC H Carrier Length Setup (REMC_CARH) Register (D[5:0]/
0x5342)
REMCL[5:0]: L Carrier Length Setup Bits in the REMC L Carrier Length Setup (REMC_CARL) Register
(D[13:8]/0x5342)
The carrier H and L section lengths can be calculated as follows:
REMCH + 1
Carrier H section length = —————— [s]
clk_in
REMCL + 1
Carrier L section length = —————— [s]
clk_in
REMCH: Carrier H section length register data value
REMCL: Carrier L section length register data value
clk_in:
Prescaler output clock frequency
The carrier signal is generated from these settings as shown in Figure 22.3.1.
Example: CGCLK[3:0] = 0x2 (PCLK-1/4), REMCH[5:0] = 2, REMCL[5:0] = 1
PCLK
PSC output clock
Count
Carrier
0
1
2
0
1
0
Carrier H section length
Carrier L section length
Figure 22.3.1: Carrier signal generation
REMC