Specifications

Table Of Contents
II-48 EPSON S1C62740 TECHNICAL SOFTWARE
CHAPTER 6: PERIPHERAL CIRCUITS (Programmable Timer)
Programming notes
(1) When initiating programmable timer count, perform program-
ming by the following steps:
1. Set the initial data to RD0–RD7.
2. Reset the programmable timer by writing "1" to PTRST.
3. Start the down-count by writing "1" to PTRUN.
(2) When the reload register (RD0–RD7) value is set at "00H", the
down-counter becomes a 256-value counter.
(3) Be sure to data reading in the order of low-order data (PT0–PT3)
then high-order data (PT4–PT7).
(4) Write the interrupt mask register (EIPT) only in the DI status
(interrupt flag = "0"). Writing during EI status (interrupt flag =
"1") will cause malfunction.
(5) Reading of interrupt factor flags is available at EI, but be careful
in the following cases.
If the interrupt mask register value corresponding to the inter-
rupt factor flags to be read is set to "1", an interrupt request will
be generated by the interrupt factor flags set timing, or an
interrupt request will not be generated.
(6)
If R01 terminal is program for PTOVF output, then R01 register
(D4H, D1) must be set as "0", and R01 terminal output the fre-
quency = (PT Input predivided frequency)/[(PT reload register) * 2].
If R01 terminal is program for DC output, then PTR01 (E9H, D3)
must be set as "0".