Motorola MC68838 User Manual page 34

Media access controller
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R_FLAG—Current Value of R_FLAG
In general, this bit indicates whether the last token received was a restricted token or a
nonrestricted token.
0 = A nonrestricted token FC is received, the MAC receiver signals the reception of a
LOWER_CLAIM, MY_CLAIM, HIGHER_CLAIM, OTHER_BEACON, or
MY_BEACON, or the MAC is turned off (MAC_ON = 0).
1 = A restricted token FC is received.
E_FLAG—Current Value of E-Flag
FSM_STATE—Frame State Machine State
These bits indicate the state of the frame state machine that parses the frame status field
for all frames (including those that have an odd number of data symbols).
000 = Wait_Ed—Wait for Ending Delimiter(T)
001 = Reserved
010 = Rc_4_5—Expecting 4 and 5 Indicators
011 = Rc_A_C—Expecting A and C Indicators
100 = Rc_5_x—Expecting 5 Indicator
101 = Rc_C_4—Expecting C and 4 Indicators
110 = Wait_FS_end—Wait for End of FrameStatus
111 = Rc_E_A—Expecting E and A Indicators
N_FLAG—Current Value of N-Flag
FR_PARS_STATE—Frame Parsing State Machine State
These bits indicate the state of the frame parsing state machine that parses the DA, SA,
INFO, and CRC fields to initiate the DA_Actions, SA_Actions, and CT_Actions and
control the CAM interface signals.
000 = Parse_DA—Receiving DA
001 = Parse_SA—Receiving SA
010 = Reserved
011 = Reserved
100 = Parse_FCS—Receiving possible FCS
101 = Parse_INFO—Receiving INFO field of MAC frame
110 = Parse_Value RCV—Rest of INFO field
111 = Reserved
L_FLAG—Current Value of L-Flag
H_FLAG—Current Value of H-Flag
M_FLAG—Current value of M-Flag
A_FLAG—Current Value of A-Flag
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MC68838 USER'S MANUAL
MOTOROLA

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