tmp88fw45afg TOSHIBA Semiconductor CORPORATION, tmp88fw45afg Datasheet - Page 238

• Manufacturer Part Number: tmp88fw45afg
• Description: 8 Bit Microcontroller Tlcs-870/x Series
• Manufacturer: TOSHIBA Semiconductor CORPORATION

19.3
Functional Description
19.3.1.3
(when X1 = 20 MHz).
resolution. However, because the actually obtained resolution is 25 ns, said resolution is accomplished arti-
ficially. To obtain a 12.5 ns resolution, the first, second, and third pulses are output by adding 25 ns, 0 ns,
and 25 ns, respectively. In this way, a 12.5 ns resolution is realized as being “equivalent to.”
the pulse is 3.0 μs (data “F0”: “3B” + “0”).
Pulse width = (7 high-order Bits of data × 50 ns) + (1 low-order Bit of data × 25 ns)
Figure 19-3 shows a typical waveform in 7-bit mode. (The values are for X1 = 20 MHz.)
In 6-bit mode, it is possible to generate a pulse with 3.2 μs period and approximately 313 kHz frequency
In 6-bit mode, the period is comprised of 6 bits (period = 2
The minimum equivalent width of the pulse is 0.2 μs (data “10”), and the maximum equivalent width of
Pulse width = (6 high-order bits of data × 50 ns) + (2 low-order bits of data *)
* The equivalent plus times in 2 low-order bits of data are shown below.
Figure 19-4 Shows a typical waveform in 6-bit mode. (The values are for X1 = 20 MHz.)
Note:The resolution of the LSB 1 bit (25 nsec) is a typical value and its precision is not guaranteed.
6-bit mode
"10h"
"F0h"
"11h"
Data
6 high-order bits
×
400 ns
50 ns
425 ns
Figure 19-3 7-Bit Mode
6.000 µs
6 high-order bits
3.2 µs
2-bit data
7
0 0
0 1
1 0
1 1
6.4 µs
Page 224
Varies with value of 2
2 low-order bits
Equivalent plus time
low-order bits
6 high-order bits
0
×
12.5 ns
37.5 ns
Data register
400 ns
25 ns
0 ns
50 ns
425 ns
6.000 µs
3.2 µs
6.4 µs
6
× 50 ns) and two other bits provide a 12.5 ns
TMP88FW45AFG