ST92124V1Q-Auto STMicroelectronics, ST92124V1Q-Auto Datasheet - Page 162

• Manufacturer Part Number: ST92124V1Q-Auto
• Description: 8-bit MCU for automotive
• Manufacturer: STMicroelectronics

Specifications of ST92124V1Q-Auto

• Internal Memory: Single Voltage FLASH up to 256 Kbytes, RAM up to 8Kbytes, 1K byte E3 TM (Emulated EEPROM)
• Minimum Instruction Time: 83 ns (24 MHz int. clock)

ST92124xxx-Auto/150xxxxx-Auto/250xxxx-Auto
TIMER/WATCHDOG (Cont’d)
10.1.5 Register Description
The Timer/Watchdog is associated with 4 registers
mapped into Group F, Page 0 of the Register File.
WDTHR: Timer/Watchdog High Register
WDTLR: Timer/Watchdog Low Register
WDTPR: Timer/Watchdog Prescaler Register
WDTCR: Timer/Watchdog Control Register
Three additional control bits are mapped in the fol-
lowing registers on Page 0:
Watchdog Mode Enable, (WCR.6)
Top Level Interrupt Selection, (EIVR.2)
Interrupt A0 Channel Selection, (EIVR.1)
Note: The registers containing these bits also con-
tain other functions. Only the bits relevant to the
operation of the Timer/Watchdog are shown here.
Counter Register
This 16-bit register (WDTLR, WDTHR) is used to
load the 16-bit counter value. The registers can be
read or written “on the fly”.
TIMER/WATCHDOG HIGH REGISTER (WDTHR)
R248 - Read/Write
Register Page: 0
Reset value: 1111 1111 (FFh)
Bits 7:0 = R[15:8] Counter Most Significant Bits.
TIMER/WATCHDOG LOW REGISTER (WDTLR)
R249 - Read/Write
Register Page: 0
Reset value: 1111 1111b (FFh)
Bits 7:0 = R[7:0] Counter Least Significant Bits.
162/430
9
R15
R7
7
7
R14
R6
R13
R5
R12
R4
R11
R3
R10
R2
R9
R1
R8
R0
0
0
TIMER/WATCHDOG PRESCALER REGISTER
(WDTPR)
R250 - Read/Write
Register Page: 0
Reset value: 1111 1111 (FFh)
Bits 7:0 = PR[7:0] Prescaler value.
A programmable value from 1 (00h) to 256 (FFh).
Warning: In order to prevent incorrect operation of
the Timer/Watchdog, the prescaler (WDTPR) and
counter (WDTRL, WDTRH) registers must be ini-
tialised before starting the Timer/Watchdog. If this
is not done, counting will start with the reset (un-in-
itialised) values.
WATCHDOG TIMER CONTROL REGISTER
(WDTCR)
R251- Read/Write
Register Page: 0
Reset value: 0001 0010 (12h)
Bit 7 = ST_SP: Start/Stop Bit.
This bit is set and cleared by software.
0: Stop counting
1: Start counting (see Warning above)
Bit 6 = S_C: Single/Continuous.
This bit is set and cleared by software.
0: Continuous Mode
1: Single Mode
Bits 5:4 = INMD[1:2]: Input mode selection bits.
These bits select the input mode:
ST_SP
PR7
INMD1
7
7
0
0
1
1
S_C
PR6
INMD2
INMD1
PR5
0
1
0
1
INMD2
PR4
Gated Input (Reset value)
INEN
PR3
Retriggerable Input
Triggerable Input
Event Counter
INPUT MODE
OUTMD
PR2
WROUT
PR1
OUTEN
PR0
0
0