MC908QY8CDWE Datasheet, PDF (125/232 Pages) Freescale Semiconductor, Inc – Addendum to MC68HC908QB8, rev. 3

Registers
Control Bits
M PEN:PTY
0
0X
1
0X
0
10
0
11
1
10
1
11
Table 13-4. Character Format Selection
Start Bits
1
1
1
1
1
1
Data Bits
8
9
7
7
8
8
Character Format
Parity Stop Bits
None
1
None
1
Even
1
Odd
1
Even
1
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.
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.
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 13-4). When enabled, the parity
function inserts a parity bit in the MSB position (see Table 13-2).
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 13-4).
1 = Odd parity
0 = Even parity
NOTE
Changing the PTY bit in the middle of a transmission or reception can
generate a parity error.
13.8.2 ESCI Control Register 2
ESCI control register 2 (SCC2):
• Enables these interrupt requests:
– SCTE bit to generate transmitter interrupt requests
– TC bit to generate transmitter interrupt requests
– SCRF bit to generate receiver interrupt requests
– IDLE bit to generate receiver interrupt requests
• Enables the transmitter
MC68HC908QB8 Data Sheet, Rev. 3
Freescale Semiconductor
123