DP83932C NSC [National Semiconductor], DP83932C Datasheet - Page 93

• Manufacturer Part Number: DP83932C
• Description: MHz SONICTM Systems-Oriented Network Interface Controller
• Manufacturer: NSC [National Semiconductor]

T56
T60
T63
T64
T69
T69a
T70a
T71a
T75b
T77
T77a
T77b
T78
T79a
T81
T83
T84
T85a
7 0 AC and DC Specifications
Number
Note 1 This figure shows a slave access to the SONIC when the SONIC is idle or rather not in master mode If the SONIC is a bus master there will be some
differences as noted in the Memory Arbitration Slave Access diagram The BSCK states (T1 T2 etc ) are the equivalent processor states during a slave access
Note 2 bcyc
Note 3 It is not necessary to meet the setup time for CS and SAS (T56 and T69) since these signals are asynchronously sampled Meeting the setup time for these
signals however makes it possible to use T60 to determine when SMACK will be asserted SAS may be asserted anytime before the next falling edge of the clock
that the CS is sampled on (as shown by specification T69) For multiple register accesses CS can be held low and SAS can be used to delimit the slave cycle
(T69a must be met in order to terminate and start another cycle) In this case SMACK will be asserted as soon as T69 timing is met
Note 4 T60 could range from 1 bus clock minimum to 5 bus clock maximum depending on what state machine the SONIC is in when the CS signal is asserted This
timing is not tested but is guaranteed by design This specification assumes that both T56 is met for CS and T69 is met for SAS T60 specification also assumes
that there were no wait states in the current master mode access (if CS is asserted when SONIC is in Master Mode) If there were wait states then it would increase
the T60 further
Note 5 It is not necessary to meet the setup time for SAS (T69a) since this signal is asynchronously sampled Meeting the setup time for this signal however will
ensure DSACK0 1 becomes TRI-STATE (T77b) and SMACK goes high (T79) at the falling edge of T1 Both CS and SAS could cause DSACK0 1 to deassert but
only SAS could cause DSACK0 1 to become TRI-STATE
e
bus clock cycle time (T3)
CS Asynch Setup to BSCK (Notes 3 4)
CS valid to SMACK Low (Notes 2 3 4)
Register Address Setup to SAS
Register Address Hold from SAS
SAS Asynch Setup to BSCK (Notes 3 4)
SAS Asynch Setup to BSCK (Notes 3 5)
SRW (Write) Setup to SAS
SRW (Write) Hold from SAS
BSCK to DSACK0 1 Low
CS to DSACK0 1 High (Note 5)
SAS to DSACK0 1 High (Note 5)
BSCK to DSACK0 1 TRI-STATE (Note 5)
Skew between DSACK0 1
BSCK to SMACK High (Note 5)
BSCK to SMACK Low
Register Write Data Setup to BSCK
Register Write Data Hold from BSCK
Min CS Deassert Time (Notes 2 3)
Parameter
(Continued)
Min
14
93
8
1
6
8
7
5
4
8
7
1
20 MHz
Max
14
20
24
19
19
22
5
3
Min
12
7
1
5
7
6
4
3
7
6
1
25 MHz
Max
12
18
22
17
17
20
5
3
Min
10
6
1
4
6
5
3
2
6
5
1
33 MHz
Max
10
16
20
15
15
18
5
2
Units
bcyc
bcyc
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns