UPD78F9222MC(T)-5A4-A NEC, UPD78F9222MC(T)-5A4-A Datasheet - Page 131

• Manufacturer Part Number: UPD78F9222MC(T)-5A4-A
• Description: 8BIT MCU, 4K FLASH, 256B RAM, 78F9222
• Manufacturer: NEC

Specifications of UPD78F9222MC(T)-5A4-A

• Controller Family/series: UPD78
• No. Of I/o's: 17
• Ram Memory Size: 256Byte
• Cpu Speed: 10MHz
• No. Of Timers: 4
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 4KB
• Oscillator Type: External, Internal

7.5
(1) Error when timer starts
(2) Setting of 8-bit compare register 80
(3) Note on setting STOP mode
Notes on 8-bit Timer 80
The time from starting the timer to generation of the match signal includes an error of up to 1.5 clocks. This is
because, if the timer is started while the count clock is high, the rising edge may be immediately detected and
the counter may be incremented (refer to Figure 7-6).
8-bit compare register 80 (CR80) can be set to 00H.
Before executing the STOP instruction, be sure to stop the timer operation (TCE80 = 0).
TM80 count value
Selected clock
Selected clock
Clear signal
Count pulse
TCE80
TCE80
Figure 7-6. Case Where Error of 1.5 Clocks (Max.) Occurs
00H
CHAPTER 7 8-BIT TIMER 80
User’s Manual U16898EJ5V0UD
Delay A
Delay B
If the timer is started when the selected clock is high
and if delay A > delay B, an error of up to 1.5 clocks occurs.
Count pulse
01H
Delay A
Delay B
02H
8-bit timer counter 80
(TM80)
03H
Clear signal
...
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