TC1796
Peripheral Units (Vol. 2 of 2)
Micro Link Interface (MLI)
User’s Manual
23-43
V2.0, 2007-07
MLI, V2.0
be set again by software to a value greater 0001
B
. Otherwise, each additional transmitter
parity error condition will generate a parity error event.
The transmitter parity error flag TSTATR.PE is cleared by hardware when a correct
frame transmission and TREADY has been sampled with 1 within the ready delay time.
It can be cleared by software by writing a 1 to bit SCR.CTPE. If for example, each
transmitter parity error condition should generate a transmitter parity error event,
TCR.MPE should be set to 0000
B
. The software can check for accumulated parity error
conditions by reading TCR.MPE or TISR.PEI, for the status of the latest received frame,
it can check TSTATR.PE.
Figure 23-32 Parity Error Indication for the Transmitter
Receiving Controller
The receiver always checks the parity bit of a received frame for even parity. A receiver
parity error condition is detected if the received parity bit does not match with the
internally calculated one. If no receiver parity error condition is found after the reception
of a frame, RREADY is immediately set to 1, otherwise RREADY is kept at 0 until a
defined number of RCLK cycles (determined by bit field RCR.DPE = delay for parity
error) has been elapsed. Then, RREADY is asserted high.
If a receiver parity error condition is found, the MLI receiver sets the parity error flag
RCR.PE and additionally decreases the maximum parity error counter of the receiver
RCR.MPE by 1. The maximum parity error counter RCR.MPE determines the number of
receiver parity error conditions that can be still detected until a receiver parity error event
is generated. If a receiver parity error condition is detected and RCR.MPE is becoming
0 or while it is already 0, a receiver parity error event is generated by setting bit RISR.PEI
MLI_PEIT
TREADY
TVALID
TREADY
TCLK
TCR.MDP
TDATA
P
With parity
error indication
Without parity
error indication