MC68HC908GZ60 Datasheet, PDF (205/352 Pages) Freescale Semiconductor, Inc – Microcontrollers

I/O Registers
M — Mode (Character Length) Bit
This read/write bit determines whether ESCI characters are eight or nine bits long (See Table
14-5).The ninth bit can serve as a receiver wakeup signal or as a parity bit. Reset clears the M bit.
1 = 9-bit ESCI characters
0 = 8-bit ESCI characters
Table 14-5. Character Format Selection
Control Bits
M PEN:PTY
0
0X
1
0X
0
10
0
11
1
10
1
11
Start Bits
1
1
1
1
1
1
Character Format
Data Bits Parity Stop Bits
8
None
1
9
None
1
7
Even
1
7
Odd
1
8
Even
1
8
Odd
1
Character Length
10 bits
11 bits
10 bits
10 bits
11 bits
11 bits
WAKE — Wakeup Condition Bit
This read/write bit determines which condition wakes up the ESCI: a 1 (address mark) in the MSB
position of a received character or an idle condition on the RxD pin. Reset clears the WAKE bit.
1 = Address mark wakeup
0 = Idle line wakeup
ILTY — Idle Line Type Bit
This read/write bit determines when the ESCI starts counting 1s as idle character bits. The counting
begins either after the start bit or after the stop bit. If the count begins after the start bit, then a string
of 1s preceding the stop bit may cause false recognition of an idle character. Beginning the count after
the stop bit avoids false idle character recognition, but requires properly synchronized transmissions.
Reset clears the ILTY bit.
1 = Idle character bit count begins after stop bit
:
0 = Idle character bit count begins after start bit
PEN — Parity Enable Bit
This read/write bit enables the ESCI parity function (see Table 14-5). When enabled, the parity function
inserts a parity bit in the MSB position (see Table 14-3). Reset clears the PEN bit.
1 = Parity function enabled
0 = Parity function disabled
PTY — Parity Bit
This read/write bit determines whether the ESCI generates and checks for odd parity or even parity
(see Table 14-5). Reset clears the PTY bit.
1 = Odd parity
0 = Even parity
NOTE
Changing the PTY bit in the middle of a transmission or reception can
generate a parity error.
MC68HC908GZ60 • MC68HC908GZ48 • MC68HC908GZ32 Data Sheet, Rev. 6
Freescale Semiconductor
205