RESET

The reset module is responsible for processing the reset signal into two global resets for the remaining logic. These two reset signals activate asynchronously from

the RST_N input, but will deactivate synchronous to the clock. One of these reset outputs “rst_2_gbuf” will extend the duration of the reset by a multiple of the

number of channels clock periods, to allow internal sequencing thru memory structures to initialize state to the required reset values. These two outputs, “rst_2_gbuf”

and “earlyRst_2_gbuf” are driven out of the core. These two outputs should be connected two global buffers and fed back to the core into inputs “rst” and “earlyRst”

respectively. If multiple identical Cores are instantiated into a single device, only one core’s RESET module should be used.

MEMORY MAP & REGISTERS

Each of the channels has 8 registers. The NUM_CHANNELS parameter controls the number of channels actually present. Accesses to unused channels may alias.

Device Requirements

Family

Channels

Device

Utilization

Performance

Tiles

RAMS

16

APA300

95%

16

34 MHz STD

8

APA150

83%

12

36 MHz STD

4

APA075

97%

12

39 MHz STD

ProASIC3

16

A3P400

64%

10

54/41 MHz -2/STD

ProASIC3

8

A3P400

43%

7

61/45 MHz -2/STD

ProASIC3

4

A3P400

26%

7

60/45 MHz -2/STD

ProASIC3

8

A3P250

65%

7

61/45 MHz -2/STD

ProASIC3

4

A3P125

77%

7

60/44 MHz -2/STD

Table 3: Device Utilization and Performance

Address A[m:0]

Contents

R/W

0x00 LCR[7] = 0

LCR[7] = 0

LCR[7] = 1

01 LCR[7] = 0

LCR[7] = 1

02

03

04

05

06

07

Channel 0 registers

RHR: Receive Holding Register

THR: Transmit Holding Register

BDL: Baud Divisor ILOW

R

W

R/W

IER: Interrupt Enable Register

BDH: Baud Divisor High

R/W

R/W

IIR: Interrupt Identificiation Register

FCR: FIFO Control Register

R

W

LCR: Line Control Register

R/W

MCR: Modem Control Register

R/W

LSR: Line Status Register

R

MSR: Modem Status Register

R

SPR: Scratchpad Register

R/W

08 - 0F

Channel 1 registers

10 - 17

Channel 2 registers

18 - 1F

Channel 3 registers

20 - 27

Channel 4 registers

28 - 2F

Channel 5 registers

30 - 37

Channel 6 registers

38 - 3F

Channel 7 registers

40 - 47

Channel 8 registers

48 - 4F

Channel 9 registers

50 - 57

Channel 10 registers

58 - 5F

Channel 11 registers

60 - 67

Channel 12 registers

68 - 6F

Channel 13 registers

70 - 77

Channel 14 registers

78 - 7F

Channel 15 registers