The SPI Function - The HCS12/9S12: An Introduction to Software and Hardware Interfacing - page 508

Pin

Name Function

SSOP PDIP

1, 2, 3, 6-14,
23, 24

1, 2, 3, 7-15,
26, 27

LED cathode drivers. O0 to O13 output sink current from the displays's
cathode rows.

O0 to O13

GND 4, 5, 6 4, 5, 6, 18 Ground

Segment current setting. Connect ISET to GND through series resistor R SET
to set the peak current.

ISET 15 17

BLINK 17 19 Blink clock output. Output is open-drain.

Serial data input. Data is loaded into the internal 16-bit shift register on the
rising edge of the CLK.

DIN 18 20

Serial-clock input. On the rising edge of CLK, data is shifted into the internal
shift register. On the falling edge of CLK, data is clocked out of DOUT. CLK
input is active only when CS is low.

CLK 19 21

Serial data output. Data clocked into DIN is output to DOUT 15.5 clock
cycles later. Data is clocked out on the falling edge of CLK. Output is
push-pull.

DOUT 20 22

Chip-select input. Serial data is loaded into the shift register while CS
is low. The last 16 bits of serial data are latched on CS's rising edge.

DOUT 21 23

Multiplex clock input. To use the internal oscillator, connect capacitor CSET
from OSC to GND. To use the external clock, drive OSC with a 1-MHz to 8-MHz
CMOS clock.

OSC 22 24

25-31, 34,
35, 36

28-34, 38,
39, 40

LED anode drivers. O14 to O23 output source current to the display's anode
columns.

O14 to O23

Positive supply voltage. Bypass V+ to GND with a 47- μ F bulk capacitor and a
0.1- μ F ceramic capacitor.

V+ 32, 33 35, 36, 37

Table 10.6 ■ MAX6952 4-digit matrix LED display driver pin functions

Digit O0 , O6 O7 , O13 O14 , O18 O19 , O23

Digit 0 rows (cathodes) R1 to R7

Digit 0 columns
(anodes) C1 to C5

Digit 1 columns
(anodes) C6 to C10

1 —

Digit 1 rows (cathodes) R1 to R7

Digit 2 rows (cathodes) R1 to R7

Digit 2 columns
(anodes) C1 to C5

Digit 3 columns
(anodes) C6 to C10

2 —

Digit 3 rows (cathodes) R1 to R7

Table 10.7 ■ Connection scheme for four monocolor digits

Digit O0 , O6 O7 , O13 O14 , O18 O19 , O23

Digit 0 columns (anodes) C1 to C10
The 5 green anodes

1 Digit 0 rows (cathodes) R1 to R14 —

The 5 red anodes

Digit 1 columns (anodes) C1 to C10
The 5 green anodes

2 — Digit 1 rows (cathodes) R1 to R14

The 5 red anodes

Table 10.8 ■ Connection scheme for two bicolor digits