CD2481 Datasheet, PDF (197/222 Pages) Intel Corporation – Programmable Four-Channel Communications Controller

Programmable Four-Channel Communications Controller — CD2481
9.7
9.7.1
Timer Registers
Timer Period Register (TPR)
Register Name: TPR
Register Description: Timer Period Register
Default Value: x’FF
Access: Byte Read/Write
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Binary Value
Intel Hex Address: x’D8
Motorola Hex Address: x’DA
Bit 2
Bit 1
Bit 0
9.7.2
This register provides the initialization value for the timer prescaler that is itself clocked by a
prescaled clock equal to system clock/2048. The timer prescaler establishes the clock for the
various on-chip timers (including RTPR, TTR, and the general timers available to the host in the
Synchronous modes). The minimum value loaded in this register to maintain accuracy in the timer
is 0A hex.
Receive Time-Out Period Register (RTPR) – Async Modes Only
Register Name: RTPR
Register Description: Receive Time-Out Period Register, 16-bit
Default Value: x’0000
Access: Word Read/Write
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Binary Value, bits 15 - 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Binary Value, bits 7 - 0
Intel Hex Address: x’26
Motorola Hex Address: x’24
Bit 10
Bit 9
Bit 8
Bit 2
Bit 1
Bit 0
9.7.2.1
Receive Time-Out Period Register low (RTPRl) – Async Modes Only
Register Name: RTPRl
Register Description: Receive Time-Out Period Register, Low Byte
Default Value: x’00
Access: Byte Read/Write, ASYNC Mode Only
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Binary Value, bits 7 - 0
Intel Hex Address: x’26
Motorola Hex Address: x’25
Bit 2
Bit 1
Bit 0
Datasheet
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