TMP92CZ26A

92CZ26A-58

3.4.5 Downloading a User Program via USB

(1) Connection example
Figure 3.4.5 shows an example of connections for downloading a user program via
USB (using a 16-bit NOR Flash memory device as program memory).
Note 1: The value of pull-up and pull-down resistors are recommended values.
Note 2: The PU6 and LD22 pins are assigned as PUCTL (pull-up control) output for USB. Be careful about this if the
system uses the 24-bit TFT display function.
Note 3: Since the input gates of the D+ and D- pins are always open even at unused (unaccessed) times, these pins
must be set to a fixed level to prevent flow-through current. Although the level setting is not specified in the
above diagram, be sure to fix the level of the D+ and D- pins by referring to the chapter on USB.
Figure 3.4.5 USB Connection Example
(2) USB interface specifications
When a user program is downloaded via USB, the oscillation frequency should be set
to 10.00 MHz. The transfer speed sho uld be fixed to full speed (12 Mbps).
The boot program uses the following two transfer types.
Table 3.4.14 Transfer Type s Used by the Boot Program
T ransfer Type Description
Control Transfer Used for transmitting standard requests and vendor requests.
Bulk Transfer Used for responding to vendor requests and transmitting a user program.
PC
PU6, LD22 RXD,P91
P82, 2CS
P70, RD
D+ PJ2, SRWR
D−
AM0 D0 to D15
AM1 A1 to A20
TMP92CZ26A
CE
OE
WE
D0 to D15
A0 to A19
NOR Flash
R2 = 27 Ω
PUCTL
R3 = 27 Ω
R1 = 1.5 kΩ
R4 =
100 kΩ