III PERIPHERAL BLOCK: PRESCALER
B-III-2-2
EPSON
S1C33L03 FUNCTION PART
Selecting Division Ratio and Output Control for Prescaler
The prescaler has registers for selecting the division ratio and clock output control separately for each peripheral
circuit described above, allowing each peripheral circuit to be controlled.
The prescaler's division ratio can be selected from among eight ratios set for each peripheral circuit through the use
of the division ratio selection bits. The divided clock is output to the corresponding peripheral circuit by writing
"1" to the clock control bit.
Table 2.1 Control Bits of the Clock Control Registers
Peripheral circuit
Division ratio selection bit
Clock control bit
16-bit programmable timer 0
P16TS0[2:0] (D[2:0]/0x40147)
∗
1
P16TON0 (D3/0x40147)
16-bit programmable timer 1
P16TS1[2:0] (D[2:0]/0x40148)
∗
1
P16TON1 (D3/0x40148)
16-bit programmable timer 2
P16TS2[2:0] (D[2:0]/0x40149)
∗
1
P16TON2 (D3/0x40149)
16-bit programmable timer 3
P16TS3[2:0] (D[2:0]/0x4014A)
∗
1
P16TON3 (D3/0x4014A)
16-bit programmable timer 4
P16TS4[2:0] (D[2:0]/0x4014B)
∗
1
P16TON4 (D3/0x4014B)
16-bit programmable timer 5
P16TS5[2:0] (D[2:0]/0x4014C)
∗
1
P16TON5 (D3/0x4014C)
8-bit programmable timer 0
P8TS0[2:0] (D[2:0]/0x4014D)
∗
2
P8TON0 (D3/0x4014D)
8-bit programmable timer 1
P8TS1[2:0] (D[6:4]/0x4014D)
∗
3
P8TON1 (D7/0x4014D)
8-bit programmable timer 2
P8TS2[2:0] (D[2:0]/0x4014E)
∗
4
P8TON2 (D3/0x4014E)
8-bit programmable timer 3
P8TS3[2:0] (D[6:4]/0x4014E)
∗
2
P8TON3 (D7/0x4014E)
8-bit programmable timer 4
P8TS4[2:0] (D[2:0]/0x40145)
∗
4
P8TON4 (D3/0x40145)
8-bit programmable timer 5
P8TS5[2:0] (D[6:4]/0x40145)
∗
2
P8TON5 (D7/0x40145)
A/D converter
PSAD[2:0] (D[2:0]/0x4014F)
∗
2
PSONAD (D3/0x4014F)
∗
1 to
∗
4: See Table 2.2.
Table 2.2 Division Ratio
Bit setting
7
6
5
4
3
2
1
0
∗
1
θ
/4096
θ
/1024
θ
/256
θ
/64
θ
/16
θ
/4
θ
/2
θ
/1
∗
2
θ
/256
θ
/128
θ
/64
θ
/32
θ
/16
θ
/8
θ
/4
θ
/2
∗
3
θ
/4096
θ
/2048
θ
/1024
θ
/512
θ
/256
θ
/128
θ
/64
θ
/32
∗
4
θ
/4096
θ
/2048
θ
/64
θ
/32
θ
/16
θ
/8
θ
/4
θ
/2
(
θ
= Source clock selected by PSCDT0)
Current consumption can be reduced by turning off the clock output to the peripheral circuits that are unused
among those listed above.
Note: In the following cases, the prescaler output clock may contain a hazard:
• If, when a clock is output, its division ratio is changed
• When the clock output is switched between on and off
• When the oscillation circuit is turned off or the CPU operating clock is switched over
Before performing these operations, make sure the 16-bit and 8-bit programmable timers and the
A/D converter are turned off.
Source Clock Output to 8-Bit Programmable Timer
In addition to the divided clock, the prescaler can output the source clock directly to the 8-bit programmable timer.
This function can be selected for each 8-bit timer using P8TPCKx bit.
8-bit timer 0: P8TPCK0 (D0) / 8-bit timer clock select register (0x40146)
8-bit timer 1: P8TPCK1 (D1) / 8-bit timer clock select register (0x40146)
8-bit timer 2: P8TPCK2 (D2) / 8-bit timer clock select register (0x40146)
8-bit timer 3: P8TPCK3 (D3) / 8-bit timer clock select register (0x40146)
8-bit timer 4: P8TPCK4 (D0) / 8-bit timer 4/5 clock select register (0x40140)
8-bit timer 5: P8TPCK5 (D1) / 8-bit timer 4/5 clock select register (0x40140)
When P8TPCKx is set to "1", the prescaler input clock (
θ
/1) is selected for the 8-bit timer x operating clock.
The clock output is controlled by the P8TONx bit even if P8TPCKx is set to "1".
When P8TPCKx is "0", the divided clock that is selected by P8TSx[2:0] will be output to the 8-bit timer x.
At initial reset, P8TPCKx is set to "0" and P8TSx[2:0] becomes effective.
Summary of Contents for CMOS 32-Bit Single Chip Microcomputer S1C33L03
Page 4: ......
Page 14: ......
Page 15: ...S1C33L03 PRODUCT PART ...
Page 16: ......
Page 147: ...S1C33L03 FUNCTION PART ...
Page 148: ......
Page 149: ...S1C33L03 FUNCTION PART I OUTLINE ...
Page 150: ......
Page 152: ...I OUTLINE INTRODUCTION B I 1 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 162: ...I OUTLINE LIST OF PINS B I 3 8 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 163: ...S1C33L03 FUNCTION PART II CORE BLOCK ...
Page 164: ......
Page 166: ...II CORE BLOCK INTRODUCTION B II 1 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 172: ...II CORE BLOCK CPU AND OPERATING MODE B II 2 6 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 176: ...II CORE BLOCK INITIAL RESET B II 3 4 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 224: ...II CORE BLOCK BCU Bus Control Unit B II 4 48 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 262: ...II CORE BLOCK DBG Debug Unit B II 7 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 263: ...S1C33L03 FUNCTION PART III PERIPHERAL BLOCK ...
Page 264: ......
Page 266: ...III PERIPHERAL BLOCK INTRODUCTION B III 1 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 322: ...III PERIPHERAL BLOCK WATCHDOG TIMER B III 5 4 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 415: ...S1C33L03 FUNCTION PART IV ANALOG BLOCK ...
Page 416: ......
Page 418: ...IV ANALOG BLOCK INTRODUCTION B IV 1 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 434: ...IV ANALOG BLOCK A D CONVERTER B IV 2 16 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 435: ...S1C33L03 FUNCTION PART V DMA BLOCK ...
Page 436: ......
Page 438: ...V DMA BLOCK INTRODUCTION B V 1 2 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 492: ...V DMA BLOCK IDMA Intelligent DMA B V 3 18 EPSON S1C33L03 FUNCTION PART THIS PAGE IS BLANK ...
Page 493: ...S1C33L03 FUNCTION PART VI SDRAM CONTROLLER BLOCK ...
Page 494: ......
Page 531: ...S1C33L03 FUNCTION PART VII LCD CONTROLLER BLOCK ...
Page 532: ......
Page 579: ...S1C33L03 FUNCTION PART Appendix I O MAP ...
Page 580: ......