Bus Signals; Address Bus (A23-A1); Table 2-6. Serial Module Signal Summary; Table 2-7. Jtag Signal Summary - Motorola MC68306 User Manual

Signal Name
Channel A Receiver Serial Data
Channel A Transmitter Serial
Data
Channel B Receiver Serial Data
Channel B Transmitter Serial
Data
Channel A Clear-to-Send
Channel A Request-to-Send
Channel B Clear-to-Send
Channel B Request-to-Send
Crystal Output
Crystal Input or External Clock
Parallel Input 2
Parallel Output 3
NOTES:
1. Pullup may be required, value depends on individual application. Must not be left floating.
Signal Name
Test Clock
Test Data Input
Test Data Output
Test Mode Select
Test Reset
NOTES:
3. Pin has internal pullup, but external pulldown may be required for correct initialization.

2.1 BUS SIGNALS

The following signals are used for the MC68306 bus.
2.1.1 Address Bus (A23–A1)
This 23-bit, unidirectional, three-state bus is capable of addressing 16 Mbytes of data.
This bus provides the address for bus operation during all cycles except interrupt
acknowledge cycles. During interrupt acknowledge cycles, address lines A1, A2, and A3
provide the level number of the interrupt being acknowledged, and address lines A23–A4
MOTOROLA

Table 2-6. Serial Module Signal Summary

Mnemonic
RxDA
TxDA
RxDB
TxDB
CTSA /IP0
RTSA /OP0
CTSB /IP1
RTSB /OP1
X2
X1/CLK
IP2
OP3

Table 2-7. JTAG Signal Summary

Mnemonic
TCK
TDI
TDO
TMS
TRST
MC68306 USER'S MANUAL
Input/ Three-State During
Output Bus Arbitration
Input —
Output No
Input —
Output No
Input —
Output No
Input —
Output No
Output No
Input —
Input —
Output No
Input/ Three-State During
Output Bus Arbitration
Input —
Input —
Output —
Input —
Input —
Pullup Required
(1)
(1)
(1)
Pulldown Required
4.7 K (3)
2- 5