CD1865 Datasheet, PDF (126/150 Pages) Intel Corporation – Intelligent Eight-Channel Communications Controller

CD1865 — Intelligent Eight-Channel Communications Controller
9.4.19
Modem Signal Value Request-to-Send Register
Register Name: MSVRTS
Register Description: Modem Signal Value Request-to-Send Register
Default Value: 0
Access: Write Only
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
0
0
0
0
0
Bit 2
0
8-Bit Hex Address: $29
Intel Hex Address: $52
Motorola Hex Address: $53
Bit 1
Bit 0
0
RTS
9.4.20
In the Modem Signal Value register, a write to either RTS or DTR affects the state of the other one.
This can be a problem when the CD1865 is using one of these signals for flow control and the other
one needs to be used under host control. This register writes to RTS without affecting the state of
any other bits. RTS is at bit 0.
Modem Signal Value Data-Terminal-Ready Register
Register Name: MSVDTR
Register Description: Modem Signal Value Data Terminal Ready
Default Value: 0
Access: Write Only
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
0
0
0
0
0
Bit 2
0
8-Bit Hex Address: $2A
Intel Hex Address: $54
Motorola Hex Address: $55
Bit 1
Bit 0
DTR
0
In the Modem Signal Value register, a write to either RTS or DTR affects the state of the other one.
This can be a problem when the CD1865 is using one of these signals for flow control and the other
one needs to be used under host control. This register writes to DTR without affecting the state of
any other bits. DTR is at bit 1.
Note: Before beginning any new design with this device, please contact Intel for the latest errata
information. See the back cover of this document for sales office locations and phone numbers.
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Datasheet