Datasheet

Table Of Contents
Section 11 8-Bit Timers (TMR)
REJ09B0140-0900 Rev. 9.00 Page 351 of 846
Sep 16, 2010
H8S/2215 Group
11.2 Input/Output Pins
Table 11.1 summarizes the input and output pins of the TMR.
Table 11.1 Pin Configuration
Channel Name Symbol I/O Function
0 Timer output pin 0 TMO0 Output Outputs at compare match
1 Timer output pin 1 TMO1 Output Outputs at compare match
All Timer clock input pin 01 TMCI01 Input Inputs external clock for counter
Timer reset input pin 01 TMRI01 Input Inputs external reset to counter
11.3 Register Descriptions
The TMR registers are listed below. For details on the module stop control register, refer to
section 22.1.2, Module Stop Registers A to C (MSTPCRA to MSTPCRC).
Timer counter (TCNT)
Time constant register A (TCORA)
Time constant register B (TCORB)
Timer control register (TCR)
Timer control/status register (TCSR)
11.3.1 Timer Counters (TCNT)
The TCNT registers are 8-bit up-counters. TCNT_0 and TCNT_1 comprise a single 16-bit register
so they can be accessed together by a word transfer instruction. Bits CKS2 to CKS0 in TCR are
used to select a clock. The TCNT counters can be cleared by an external reset input or by a
compare match signal A or B. Which signal is to be used for clearing is selected by bits CCLR1
and CCLR0 in TCR. When a TCNT counter overflows from H'FF to H'00, OVF in TCSR is set to
1. The TCNT counters are each initialized to H'00.