Processor Users Manual

27-8 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part IV. Communications Processor Module
27.6 Channel-SpeciÞc HDLC Parameters
Table 27-3 describes channel-speciÞc parameters for HDLC.
Table 27-3. Channel-Specific Parameters for HDLC
Offset
1
1
The offset is relative to dual-port RAM base address + 64*CH_NUM
Name Width Description
0x00 TSTATE Word Tx internal state. To start a transmitter channel the user must write to TSTATE
0xHH80_0000. HH is the TSTATE high byte described in Section 27.6.1, ÒInternal
Transmitter State (TSTATE).Ó
0x04 ZISTATE Word Zero-insertion machine state.(User-initialized to 0x10000207 for regular channel, and
0x30000207 for inverted channel)
0x08 ZIDATA0 Word Zero-insertion high word data buffer (User-initialized to 0xFFFFFFFF)
0x0C ZIDATA1 Word Zero-insertion low word data buffer (User-initialized to 0xFFFFFFFF)
0x10 TBDFlags Hword TxDB ßags, used by the CP (read-only for the user)
0x12 TBDCNT Hword Tx internal byte count. Number of remaining bytes in buffer, used by the CP (read-only
for the user)
0x14 TBDPTR Word Tx internal data pointer. Points to current absolute data address of channel, used by the
CP (read-only for the user)
0x18 INTMSK Hword ChannelÕs interrupt mask ßag. See Section 27.6.2, ÒInterrupt Mask (INTMSK).Ó
0x1A CHAMR Hword Channel mode register. See Section 27.6.3, ÒChannel Mode Register (CHAMR).Ó
0x1C TCRC Word Temp transmit CRC. Temp value of CRC calculation result, used by the CP (read-only for
the user)
0x20 RSTATE Word Rx internal state. To start a receiver channel the user must write to RSTATE
0xHH80_0000. HH is the RSTATE high byte described in Section 27.6.4, ÒInternal
Receiver State (RSTATE).Ó
0x24 ZDSTATE Word Zero-deletion machine state (User-initialized to 0x00FFFFE0 for regular channel and
0x20FFFFE0 for inverted channel)
0x28 ZDDATA0 Word Zero-deletion high word data buffer (User-initialized to 0xFFFFFFFF)
0x2C ZDDATA1 Word Zero-deletion low word data buffer (User-initialized to 0xFFFFFFFF)
0x30 RBDFlags Hword RxBD ßags, used by the CP (read-only for the user)
0x32 RBDCNT Hword Rx internal byte count. Number of remaining bytes in buffer, used by the CP (read-only
for the user)
0x34 RBDPTR Word Rx internal data pointer. Points to current absolute data address of channel, used by the
CP (read-only for the user)
0x38 MFLR Hword Maximum frame length register. DeÞnes the longest expectable frame for this channel.
(64-Kbyte maximum). The remainder of a frame that is larger than MFLR is discarded
and the LG ßag is set in the last frameÕs BD. An interrupt request might be generated
(RXF and RXB) depending on the interrupt mask. A frameÕs length is considered to be
everything between ßags, including CRC. No more data is written into the current buffer
when the MFLR violation is detected.
0x3A MAX_CNT Hword Max_length counter, used by the CP (read-only for the user)
0x3C RCRC Word Temp receive CRC, used by the CP (read-only for the user)